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Readiness to adopt the self-management approach to cope with chronic pain in fibromyalgic patients
Pain 90 (2001) 37±45
www.elsevier.nl/locate/pain
Readiness to adopt the self-management approach to cope with chronic pain in ®bromyalgic patients Arie Dijkstra a,*, Johan W.S. Vlaeyen b, Heidi Rijnen c, Warren Nielson d a
Department of Clinical and Health Psychology, Leiden University, P.O. Box 9555, 2300 RB, Leiden, The Netherlands b Department of Medical, Clinical and Experimental Psychology, Maastricht University, Maastricht, The Netherlands c Pulmonary Rehabilitation Centre, Hornerheide, The Netherlands d Arthritis Care Centre, London, Ontarion, Canada Received 1 March 2000; received in revised form 7 July 2000; accepted 17 July 2000
Abstract The effectiveness of cognitive-behavior therapy aimed at helping patients with the acquisition of self-management skills to cope with pain, is thought to depend partly on the patients' willingness to adopt a self-management approach. Some patients may not believe that selfmanagement will be helpful while others have decided to adopt it and others already apply the self-management skills in their daily lives. The present study explored the concept of `Readiness to change' in a population of Dutch ®bromyalgic patients. A self-report questionnaire was completed by 321 patients. Factor analysis revealed three scales, each assessing the characteristic of one stage of readiness to change, the Precontemplation, Contemplation and Action scale. Firstly, the reliabilities of these scales were 0.61, 0.86 and 0.61, respectively, and only the latter two scales correlated signi®cantly (r 0:14). Secondly, the scales were validated using subscales from the Multidimensional Pain Inventory, beliefs on the credibility of the self-management approach and subscales from the Illness Perception Questionnaire. These subscales explained 5, 22 and 8% of the variance of the scores on the Precontemplation, Contemplation and the Action scales, respectively. Thirdly, on the basis of the three scale scores, over 80% of the ®bromialgia patients could be classi®ed into one of ®ve potentially psychological relevant subgroups: Precontemplation, Contemplation, Preparation, Action and Relapse. The data suggest that improvements in operationalizations of the Precontemplation and Action dimensions of readiness to change are needed and that the theoretical foundation of readiness to change needs further development. q 2001 International Association for the Study of Pain. Published by Elsevier Science B.V. All rights reserved. Keywords: Self-management approach; Coping; Chronic pain; Cognitive-behavior therapy; Readiness to change
1. Introduction Besides the medical approach to treat chronic pain, psychological interventions may be applied to manage pain and its negative psychological and social consequences. The effectiveness of cognitive-behavior therapies with regard to coping with pain has been investigated and veri®ed in several studies (Turk et al., 1983; Nielson et al., 1992; Vlaeyen et al., 1996; Morley et al., 1999). In these therapies, patients may learn behavioral and cognitive self-management skills to cope with pain. The effectiveness of cognitive-behavior therapy depends on several therapist, treatment and patient characteristics (Bergin and Gar®eld, 1994). The patients' willingness to adopt the cognitive-behavioral approach is one example of a patient characteristic that determines effectiveness (Prochaska et al., 1992a). That is, when patients are * Corresponding author. Tel.: 131-71-527-4036; fax: 131-71-527-3619. E-mail address: [email protected] (A. Dijkstra).
not really convinced that self-management can be bene®cial, they may adhere to it as long as they are in therapy but they will be prone to relapse. This patient characteristic of willingness to adopt a certain new behavior is conceptualized as `readiness to change' (McConnaughy et al., 1983, 1989; Prochaska, 1984). Readiness to change refers to behavior change as a process instead of a discrete event: People move from no intention or motivation to change to the internalization of the new behavior. Several stages of readiness to change have been de®ned (Prochaska et al., 1992a). The ®rst stage is the precontemplation stage in which patients have not yet adopted the new behavior and are not motivated to change their behavior. According to Prochaska and DiClemente (1983), precontemplators: `¼tend be defensive and avoid changing their thinking and behavior¼' (p. 391). The second stage is the contemplation stage in which patients have not yet adopted the new behavior but think about chan-
0304-3959/01/$20.00 q 2001 International Association for the Study of Pain. Published by Elsevier Science B.V. All rights reserved. PII: S 0304-395 9(00)00384-5
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A. Dijkstra et al. / Pain 90 (2001) 37±45
ging. However, they have not yet made a commitment to take action. The third and more recently added stage is the preparation stage in which people are planning to engage in the new behavior on the short-term. They have made a commitment to do so and they may already experiment or engage partly in the new behavior. The fourth stage is the action stage in which people execute the new behavior. However, this still costs a lot of energy. The ®fth stage is the maintenance stage: `¼in which people work to prevent relapse and consolidate the gains attained during action.' (p. 1104; Prochaska et al., 1992a). In earlier versions of the model the relapse stage was recognized but later removed from the model because it was not considered to be a stage but a regression to a former stage (Davidson, 1992; Prochaska et al., 1992b). Stages of readiness to change have been assessed in the change process in different populations, such as clinical (McConnaughy et al., 1989) and non-clinical populations (Prochaska et al., 1992a,b) and in different behaviors, such as excessive drinking (Rollnick et al., 1992; Budd and Rollnick, 1996) and weight control (Prochaska et al., 1992a). These studies used continuous readiness to change scales based on the original Readiness to Change Questionnaire of McConnaughy et al. (1983). This 32-item measure distinguishes between four stages of readiness to change, not including the newer preparation stage (Prochaska et al., 1992a; McConnaughy et al., 1989), whereas the 12-item measure distinguishes between three stages, not including the preparation and maintenance stage (Rollnick et al., 1992; Heather et al., 1993). Using these quantitative measures, people score higher or lower on characteristics of each stage. Readiness to change is expected to predict successful behavior change. That is, more people with high readiness to change are expected to change their behavior successfully compared to people with low readiness to change. Predictive validity of the stages might imply that to increase the effectiveness of the behavior therapy, the patients' readiness to change should be increased. Furthermore, it might implicate that patients in different stages of readiness to change may need stage-matched therapies (Dijkstra et al., 1998). However, the data on predictive validity from studies classifying patients on the basis of quantitative Readiness to change measures are disappointing (Heather et al., 1993; Treasure et al., 1999; Wilson et al., 1997), suggesting that there is a need for more valid measures of stages of readiness to change. No data are available with regard to the readiness to adopt a behavioral approach in patients with the ®bromyalgic syndrome. Individual ®bromyalgic patients might differ with regard to: (1) the extent that they belief that selfmanagement will bene®t them (precontemplation dimension); (2) the extent that they have a need for information on self-management of their pain (contemplation dimension); (3) the extent to which they already engage in selfmanagement (action and maintenance dimension). The
Readiness to change theory predicts that these characteristics of individual patients will be associated with drop-out and treatment success and that on the basis of the scores on these characteristics patients can be matched to treatments, for example, to a motivation-oriented or an action-oriented treatment. To the best of our knowledge, only three studies investigated the readiness to change concept in pain patients (Keefe and Caldwell, 1997, 2000; Kerns and Rosenberg, 2000). Kerns et al. (1997) identi®ed four scales with moderate to good reliability ± the precontemplation, the contemplation, the action and the maintenance scales ± using a 30item Readiness to change questionnaire in a sample of patients with chronic pain. The four scales showed interpretable relations with several criterion variables. For example, the precontemplation scale had a positive relation to patients' belief in medical pain treatment and a negative relation to patients' belief in the extent to which they can exert personal control over their pain. In a later study, Kerns and Rosenberg (2000) found that pretest scores on the precontemplation and contemplation scales predicted whether or not patients engaged in a self-management treatment for their chronic pain. Among patients who did engage in the self-management treatment, however, the Readiness to change scores were not related to treatment outcomes. Furthermore, decreases in precontemplation scores and increases in action and maintenance scores were related to decreases in pain intensity, disability and affective distress. These data provide preliminary support for the predictive validity and utility of a 30-item Readiness to change questionnaire regarding self-management of chronic pain. Keefe et al. (2000) assessed readiness to change in a sample of arthritis patients. Using cluster analyses they were able to identify ®ve clusters of patients with different con®gurations of scores on the precontemplation, the contemplation, the action and the maintenance scale. The ®rst three clusters clearly referred to the precontemplation stage (high on precontemplation and lower on the other scales), the contemplation stage (high on contemplation and lower on the other scales), the preparation stage (high on contemplation and action and lower on the other scales). The two additional clusters referred to patients in the action and the maintenance stage although these patients also scored higher on some other scales. The authors conclude that they were able to identify ®ve distinct subgroups that are consistent with the theoretical model. The goal of the present study was to explore the psychometric properties and the concurrent validity of a Dutch version of a questionnaire assessing readiness to change in a sample of patients with ®bromyalgia. First, the scale development will be described. On the basis of earlier studies (Kerns et al., 1997; McConnaughy et al., 1989) it is expected that at least three reliable scales ± each referring to another stage of readiness to change ± can be distinguished: the Precontemplation scale, the Contemplation scale and the Action scale. On the basis of the assumption that the three scales refer to one underlying dimension of
A. Dijkstra et al. / Pain 90 (2001) 37±45
readiness to change, it is expected that the scales will correlate signi®cantly (Rollnick et al., 1992). Second, the concurrent validity of the resulting scales will be studied by relating the Readiness to change measures to the validated Dutch version of the Multidimensional Pain Inventory (MPI; Lousberg et al., 1999), to beliefs on the credibility of the self-management of pain and the medical management of pain (CPT) and to the Illness Perception Questionnaire (IPQ; Weinman et al., 1996). It is expected that these measures will be related meaningfully to the three Readiness to change scales, in that they can be interpreted as being causes or effects of the patients' readiness to change. Stage classi®cation may serve the practical function of assessing patients' readiness to change before enrolment in cognitive-behavior therapy. Therefore, third, individuals will be classi®ed into one stage on the basis of the three Readiness to change scale scores and an attempt will be made to offer a psychological typology of patients in each stage using the variables from the validation tests. 2. Method 2.1. Recruitment and participant characteristics Participants were recruited from the Dutch Society of Fibromyalgic Patients. From the 9200 members, 745 patients were randomly selected using a computerized random number generator. These patients were subsequently sent the questionnaire, a pre-paid return and an accompanying letter explaining the procedure, the utility and conditions of the study. From the 745 patients who received a questionnaire, 339 (45.5%) questionnaires were returned of which 321 were ®lled in completely and were used in the present study. Most participants were female (92%), the average age was 48 years, and on average patients had suffered from pain for 16 years. Sixty percent had a low education level, which, in the diverse Dutch schooling system, refers to the level of vocational training. Furthermore, 74% were married, 5% were widowed, 8% were divorced and 12% were unmarried. Forty percent of the participants received disability compensation. 2.2. Questionnaire The questionnaire assessed several physical and psychosocial constructs. Only the questions and scales relevant for the present study will be presented here. 2.2.1. The stages of Readiness to change measure (SRC) First, 32 items for the Readiness to change measure were derived from an unpublished English Readiness to Change Questionnaire (Nielson and Vlaeyen, 1996) which had been based on McConnaughy et al.'s (1989) measure of readiness to change. The items were adapted for use with chronic pain patients and they referred to readiness to adopt a selfmanagement approach to cope with pain. The characteris-
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tics of four stages of readiness to change were assessed each with eight items. A high score on an item such as: `I don't think I need to change the ways I manage my pain', was considered to be indicative of the precontemplation stage. A high score on an item such as: `I would like to have more ways to manage my pain', was considered to be indicative of the contemplation stage. A high score on an item such as: `I am working hard to manage my pain', was considered to be indicative of the action stage. A high score on an item such as: `I now need support to keep managing my pain', was considered to be indicative of the maintenance stage. The items could be scored from `I do not agree at all' (22) to `I totally agree' (12). Second, after translation in Dutch the face validity of the items was assessed by asking eight researchers with thorough knowledge of the readiness to change concept from the Department of Health Education to categorize each of the 32 items to one particular stage of readiness to change. The items meant to assess the precontemplation stage, the contemplation stage and the action stage were all interpreted according to expectations. However, six of the eight items assessing the maintenance stage were wrongly classi®ed by several experts from the Department of Health Education. Most of the time the items were mistakenly categorized as items assessing the precontemplation stage. Looking more closely at the maintenance items it seemed they all referred to an impending danger of relapse. It might be concluded that the maintenance items were classi®ed as precontemplation items because of a similar underlying dimension of low motivation or a lack of con®dence in the ability to change the behavior (McConnaughy et al., 1989). Thus, the maintenance items were removed from the questionnaire leaving 24 items assessing the precontemplation stage, the contemplation stage and the action stage. 2.2.2. The Multidimensional Pain Inventory (MPI) This inventory assesses several aspects of the impact of pain in patients' lives. The Dutch version of this questionnaire, containing nine subscales, is validated and has proven to have good internal consistency and test-retest reliability (Lousberg et al., 1999). The following scales were distinguished: Pain intensity (two items; Cronbach's alpha (a ) 0.88), Interference (nine items; a 0.82), Life control (three items; a 0.84), Affective distress (three items; a 0.77), Social support (three items; a 0.87), Punishing responses (three items; a 0.85), Solicitous responses (six items; a 0.73), Distracting responses (three items; a 0.61) and General activity (18 items; a 0.70). The item anchors were item-speci®c. For example, a question about the extent of the experienced pain could be scored from `no pain at all' (0) to `a great deal of pain' (6), while a question on control could be scored from `no control' (0) to `a great deal of control' (6). 2.2.3. Credibility of pain treatments (CPT) In order to assess to what extent Readiness to change was
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A. Dijkstra et al. / Pain 90 (2001) 37±45
associated with beliefs about the credibility of medical and behavioral treatments, participants read a short description of a medical and a behavioral pain treatment. They then were asked two questions with regard to each pain treatment: `Do you think this treatment would be effective; (1) for you; (2) for others'. The items could be scored on a Visual Analogue Scale from: `not effective at all' to `very effective' (based on Borkovec and Nau (1972)). 2.2.4. Illness Perception Questionnaire The Illness Perception Questionnaire (IPQ; Weinman et al., 1996) assesses the attributions patients make with regard to the causes of (ten items) and in¯uences on (ten items) their pain. Four subscales were formed. Two scales assessed the perceived biological causes (®ve items; a 0.65) and the perceived biological in¯uences (®ve items; a 0.64). The items referred to nutritional, genetic, viral, environmental and medical causes of or in¯uences on the pain complaints. Furthermore, two scales assessed the perceived psychosocial causes (four items; a 0.77) and the perceived psychosocial in¯uences (four items; a 0.81). The items referred to life-style, stress, other people and mental condition as causes of or in¯uences on the pain complaints. One item, on `chance' as a cause or in¯uence, was removed because it lowered the reliability of both psychosocial scales. The items could be scored from:'I do not agree at all' (1) to `I totally agree' (5). 3. Results 3.1. Scale development A Principal Component Analyses was conducted on the 24 items assessing readiness to change. The number and
quality of the components was determined by: (a) the interpretability of the proposed components; (b) the extent to which an item loaded uniquely on the expected component; (c) the changes in explained variance of the components. Furthermore, the internal consistency (Cronbach's a ) was assessed to learn to what extent the items in one scale referred to the same underlying factor. Using these criteria, another six items were removed. Table 1 shows the remaining items and their factor loadings. The Precontemplation scale was composed of ®ve items, with an average inter-item correlation of 0.25 and a 0.63. The Contemplation scale was composed of seven items, with an average inter-item correlation of 0.46 and a 0.86. The Action scale was composed of six items, with an average inter-item correlation of 0.21 and a 0.61. The internal consistencies of the precontemplation and the action scales were moderate but suf®cient in the present developmental phase. The correlations among the three scales were computed: Only the contemplation and action scale correlated signi®cantly but low (r 0:14). 3.2. Concurrent validity To investigate the concurrent validity of the three Readiness to change measures, the scale scores were predicted by the MPI scales, the CPT beliefs and the IPQ scales, using three multivariate regression analyses (Table 2). The independent variables were entered in blocks: (1) demographics (age, level of education, gender and living conditions); (2) motivating factors (pain intensity, interference and distress); (3) social in¯uence (support, punishing and solicitous responses, distraction); (4) control and attribution (the IPQ scales, control, activity); (5) CPT beliefs. The data on the prediction of the Precontemplation scores
Table 1 Items and factor loadings of the three factors that each comprise a Readiness to change scale a Precontemplation I do have problems in coping with my pain, but many people do. Why should I elaborate on that? I would rather leave the situation as it is, than start searching for alternatives. Why should I change? Let the doctor take care of my pain. All that talking about psychology and my pain bores me. Why don't people just act normal. I don't have to change my way of coping with the pain because my coping has nothing to do with it. I really think I should change the way I cope with my pain. It would be worthwhile to be able to in¯uence my pain myself. I wish I had some more ways to cope with my pain. Skills to in¯uence my pain myself could be helpful for me. I wish that someone had some good advice for me so that I would suffer somewhat less from my pain. I have been thinking for a while that I would like to learn to cope differently with my pain. I hope I could get some more insight into my pain. I am actively trying to ®nd ways to cope with my pain differently. It is easy to talk about coping differently with your pain but I am, at least, doing it differently. Although my pain still in¯uences my life negatively, I keep on trying to in¯uence the pain myself. I often feel limited by my pain but I am working on it. I do things to in¯uence my pain. I am working hard to get the pain under my control. a
All loadings .0.40 are depicted.
0.68 0.56 0.45 0.72 0.61
Contemplation
0.76 0.58 0.82 0.67 0.77 0.76 0.71
Action
0.60 0.60 0.41 0.57 0.45 0.75
A. Dijkstra et al. / Pain 90 (2001) 37±45 Table 2 Multivariate regression analyses with the Readiness to change scales as dependent variables and the demographic variables, the MPI scales, the CPT scales and the IPQ scales as predictors a Beta
Cumulative adjusted R 2
Precontemplation Education Age Will self-management of pain help you?
20.24*** 0.19** 20.21***
0.09 0.11 0.16
Contemplation Distress Interference Biological in¯uences Will self-management of pain help you?
0.32*** 0.18** 0.15** 0.12*
0.15 0.19 0.21 0.22
Action Age Interference Distraction Control Will self-management of pain help others?
0.18** 0.17** 0.14* 0.11 ² 0.19**
0.02 0.04 0.05 0.07 0.10
a ²
P , 0:10; *P , 0:05; **P , 0:01; ***P , 0:001. In three multivariate regression analyses, the Readiness to change scale scores were predicted by the independent variables that were entered in blocks: (1) demographics (age, level of education, gender and living conditions); (2) MPI motivating factors (pain intensity, interference and distress); (3) MPI social in¯uence (support, punishing and solicitous responses, distraction); (4) MPI control and IPQ attribution (control, activity and IPQ-scales); (5) CPT beliefs.
revealed that level of education, age and the credibility of the self-management approach for the patient him/her self were signi®cant predictors, explaining 16% of its variance. The data on the prediction of the Contemplation scores revealed that levels of distress and interference and beliefs on the biological in¯uences and credibility of the selfmanagement approach were signi®cant predictors, explaining 22% of its variance. The data on the prediction of the Action scores revealed that age, levels of interference, distraction, control and the credibility of the self-management approach were signi®cant predictors, however, explaining only 10% of its variance.
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stage. In this way patients could be classi®ed in the precontemplation stage (1; 2 ; 2 ) the contemplation stage (2; 1 ; 2 ); or in the action stage (2; 2 ; 1 ). In addition, patients with a low score on the precontemplation scale in combination with high scores on the contemplation and action scales (2; 1 ; 1 ) were considered to be in the preparation stage (Heather et al., 1993). These patients are considered to have characteristics of both adjacent stages. Finally, patients with a high score on precontemplation, a low score on contemplation but a high score on action (1; 2 ; 1 ) were considered to be in danger of relapse. Table 3shows frequencies and percentages of patients that could be classi®ed in one stage. Using the original three stage model, only 29.3% of the patients were in one particular stage. Adding the preparation stage, the percentage of classi®able patients increased to 78.5%. Recognizing patients in danger of relapse, the percentage increased to 83.5%. The remaining 16.4% patients were designated `unclassi®able'. 3.4. Stage typology Figs. 1 and 2 show the mean scores on the MPI, the CPT and the IPQ scales of the six groups of ®bromyalgia patients: patients in the precontemplation stage, the contemplation stage, the preparation stage and the action stage and patients who are in danger of relapse and the unclassi®able groups. The groups were compared to each other using analysis of variance. First of all, the groups of patients were compared on the MPI scales. 3.4.1. MPI impact The groups differed signi®cantly on the experienced pain (P , 0:001), the interference of pain (P , 0:001) and level of distress (P , 0:001). The upper graph in Fig. 1 (MPI impact factors) shows that precontemplators have about the same levels of pain and interference as contemplators and preparers but that they have a more positive mood (score lower on distress). Patients in action seem to be Table 3 Classi®cation of patients in one stage group using positive (1) and neutral or negative (2) scores on the three scales a
3.3. Classifying patients into one stage
Stage groups
Pc/C/Act-scales
Frequency
Percentage
For clinical purposes it may be bene®cial to be able to classify patients into one discrete stage. That is, people could then be considered to be in the precontemplation, the contemplation stage or the action stage. In line with Rollnick et al. (1992); Heather et al. (1993), the present average scale scores, ranging from 22 to 12, were used: When a patient had a score of zero or lower than zero on a scale, the patient was considered to not have the characteristic measured by that speci®c scale. Thus, a patient who scored .0 on the precontemplation scale but #0 on both other scales was considered to be in the precontemplation
Precontemplators Contemplation Preparation Action Relapse Unclassi®able 1 Unclassi®able 2 Unclassi®able 3
122 212 211 221 121 112 111 222
4 22 158 68 16 3 38 12
1.2 6.9 49.2 21.2 5 0.9 11.8 3.7
a Pc, Precontemplation scale; C, Contemplation scale; Act, Action scale. Plus (1) means that the score on the particular scale is higher than zero. Minus (2) means that the score on the particular scale is equal or lower than zero.
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A. Dijkstra et al. / Pain 90 (2001) 37±45
and borderline signi®cantly on activity (P , 0:10). The lower graph in Fig. 1 (MPI control and activity) shows that precontemplators experience more control than patients in contemplation and preparation, while patients in action score the highest. With regard to the MPI scale `general activity', especially contemplators score high (even somewhat higher than those in action) and preparers score low. Patients in danger of relapse and the unclassi®able groups scored moderate. 3.4.4. CPT scales The groups only differed borderline signi®cantly on the belief that self-management of pain is an effective means to cope with pain (P , 0:10). The upper graph in Fig. 2 (CPT scales) shows that precontemplators scored the lowest, contemplators, preparers and patients in action scored higher while patients who are in danger of relapse, again, scored lower. 3.4.5. IPQ scales The groups only differed borderline signi®cantly on the psycho-social causes and signi®cantly on psycho-social in¯uences (P , 0:10 and P , 0:05, respectively). The lower graph in Fig. 2 (IPQ scales) shows that precontemplators scored lower than the other patient groups. Fig. 1. The scores on the MPI subscales for patients in each stage group in standardized T-scores (mean 50; Standard Deviation 10). Pc, precontemplation; C, Contemplation; Pr, Preparation; Act, Action; Rel, prone to Relapse; Uncl, Unclassi®able. ***P , 0:001 (vertical); **P , 0:05 (vertical); *P , 0:10. Signi®cance's are of the overall F-test comparing all six groups of patients.
able to decrease the pain and interference and they also have more positive mood. In patients who are in danger of relapse and patients in the disengaged group things seem to be worse again. 3.4.2. MPI social in¯uence The groups differed borderline signi®cantly on social punishment (P , 0:10) and signi®cantly on social support (P , 0:05). The middle graph in Fig. 1 (MPI social in¯uence) shows that precontemplators perceive fewer punishing and distracting social in¯uences than patients in contemplation and preparation and more supporting and solicitous in¯uences than patients in contemplation and preparation. In particular contemplators perceive many punishing and few supporting social in¯uences. In the remaining groups few differences seem present although the low perceived support of patients who are in danger of relapse is striking. 3.4.3. MPI control and activity The groups differed signi®cantly on control (P , 0:001)
Fig. 2. The scores on the credibility beliefs and the IPQ attribution subscales for patients in each stage group. Upper graph in standardized T-scores (mean 50; Standard Deviation 10). Pc, precontemplation; C, Contemplation; Pr, Preparation; Act, Action; Rel, prone to Relapse; Uncl, Unclassi®able. ***P , 0:001 (vertical); **P , 0:05 (vertical); *P , 0:10. Signi®cance's are of the overall F-test comparing all six groups of patients.
A. Dijkstra et al. / Pain 90 (2001) 37±45
4. Discussion The goal of the present study was to explore the psychometric properties and the validity of a Dutch version of the Readiness to change questionnaire in a sample of patients with fybromyalgia. The three scales were considered to asses the readiness to change the way to cope with the pain. The reliability of the Contemplation scale was 0.86 and the reliabilities of the Precontemplation and the Action scales were just above 0.60, thereby threatening the validity of both measures. The validity of these scales was further compromised by the ®nding that the variables used to assess the concurrent validity of the three scales explained 22% of the variance in the Contemplation scores, but only 5 and 8% of the Precontemplation and Action scores, respectively. Although the strength of the relations between the Readiness to change scales on the one hand and the concurrent validity measures on the other hand were only moderately to weak, the relations could be interpreted meaningfully. Patients' scores on the Precontemplation scale were related to the credibility of the self-management approach. Low credibility of the self-management solution can be regarded as one of the causes of low readiness to change (Prochaska and Prochaska, 2000). This interpretation is in line with the ®nding of Kerns et al. (1997) that the higher patients scored on the belief that their pain could be cured medically, the higher their scores on the Precontemplation scale. Patients' scores on the Contemplation scale, ®rst, were predicted by the level of distress and the extent to which the pain interfered with the normal life routine. Distress and interference may be viewed as motives to contemplate changing. This is in line with the conception of contemplators becoming motivated to change because they start to process information on the pros and cons of their current behavior (Prochaska et al., 1992a). Furthermore, the contemplation scores were higher as patients found the self-management approach more credible. The credibility may be viewed as a precondition to become motivated in the ®rst place. The ®nding that the biological attributions of complaints were a predictor of contemplation is a puzzling ®nding and in contrast with the ®ndings of Kerns et al. (1997). Our ®nding might be a sign that the more patients contemplate changing, the more they become to believe that at least a part of their complaints is hard to change because of biological roots. Patients' scores on the Action scale were predicted by interference, social distraction, experienced control and the credibility of self-management to help others. Interference, again, might be the motive to be active, while experiencing more control might be an effect of becoming more active. On the other hand, when patients start coping actively with their pain, the interference of pain with their lives might become more salient. Furthermore, the more active patients were, the more the spouse tried to distract the patient from the pain. Acknowledging the important in¯uence of the spouse on the pain (Block et al., 1981; Flor et al., 1987), this might mean that, both patient and spouses, become active. It might even mean that the readiness to adopt
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a self-management approach is a function of the patient's family system. Lastly, the ®nding that the credibility of the self-management approach to help others was a predictor, might mean that the effects of the activities patients engage in fall somewhat short of their expectations but that they still see some potential bene®ts in the approach for others. In conclusion, the concurrent validity of the Precontemplation and Action scales left something to be desired. With regard to the relations among the three Readiness to change scales, several authors predicted that the three scales will correlate (Budd and Rollnick, 1996; Kerns et al., 1997; McConnaughy et al., 1983, 1989; Rollnick et al., 1992), thereby indicating an unitary underlying dimension of readiness to change. In the present study, however, only the Contemplation and Action scales correlated signi®cantly but low (r 0:14). Thus, the present data do not support the notion of a single underlying construct of readiness to change. Seemingly, a patient can think about adopting the self-management approach as measured by the Contemplation scale but still resist changing as measured by the Precontemplation scale. It might be that the Precontemplation scale is more a measure of temporary communicationinduced reactance or defensiveness instead of a measure of low readiness. Another explanation lies in a possible lack of clarity with regard to the behavior to which the items refer (also see Treasure et al., 1999). In studies on alcohol intake the behavior under study ± not drinking (McConnaughy et al., 1983, 1989; Rollnick et al., 1992) ± is more unequivocal. In the present study, we assessed the readiness to `change the way to cope with the pain'. This formulation may have been too broad. That is, we might expect that their is little consensus about ways to cope with pain among patients. One solution would be to focus the items on one speci®c and identi®able behavior, for example, `engaging in a short relaxation exercise'. The proportion of subjects that can be classi®ed in one stage ± on the basis of the con®guration of the three scale scores ± is another way to learn about the Readiness to change scales. Although only 29% of the patients could be classi®ed using the three stage model (Precontemplation, Contemplation and Action), the addition of the Preparation stage group increased the percentage of classi®able patients from 29.3 to 78.5%. Heather et al. (1993) report a similar ®nding of an increase of the percentage of classi®able people from 40 to 75% when they added the Preparation stage to their model. In the present sample of ®bromyalgia patients, almost 50% of the patients were in the Preparation, that is, they scored above zero on the Contemplation and the Action scales and below zero on the Precontemplation scale. In other words, those patients indicate that they are active in coping with their pain (doing something, being active, working on) but at the same time have a need for further change. It might be concluded that half of the ®bromyalgia patients sampled have not yet found a satisfactory level of coping with their pain. The present cross-sectional data can not be conclusive
44
A. Dijkstra et al. / Pain 90 (2001) 37±45
about whether patient move through psychological stages in a ®xed sequence. Therefore, at the best, the above classi®cation refers to subgroups of ®bromyalgia patients. On the basis of the scores on the MPI-, CPT- and IPQ-questionnaires, the following typology of patients in the different subgroups can be formed. Precontemplators seem to be stuck in a selfpreserving state: Despite high levels of pain and interference (even somewhat higher than patients in contemplation and preparation) they manage to keep their spirits up (low distress scores) and they have developed an illusion of control. This interpretation is in line with the notion that people in the precontemplation stage are defensive to potential changemotivating information (Miller and Rollnick, 1991; Prochaska and Prochaska, 2000). This psychological state is further protected by the perception of low credibility of the effectiveness of self-management and low psychosocial attributions. Lastly, the social in¯uence seems to further reinforce this state with high levels of support and solicitous responses and low levels of punishing and distracting responses. This description seems in line with the ®nding of Kerns et al. (1997) that higher Precontemplation scores were related to a measure of wishful thinking and dependency on others. In contrast, contemplators seem to be in an unstable state: High levels of interference, high distress, low levels of control and they do believe that self-management could help and that their pain is partly in¯uenced by psychosocial factors. Whereas precontemplators' situation seems socially reinforced, contemplators report high levels of punishing responses of the spouse and low levels of support. Patients in the preparation group were very similar to those in the contemplation group. However, they report renewed, and maybe qualitatively different, social support and they score lower on activity. Patients in the preparation group seem to engage less in normal daily activities. Given the items anchors, from never doing this to doing this very often, the low activity score might indicate that those patients are painfully aware of the limitations they have. Patients in the action group show that coping actively with their pain helps: They speci®cally report lower levels of pain and interference, lower distress and more control. They believe that self-management also can help others, probably because they experience it themselves. Patients who are active but in danger of relapse report lower social support and more pain, interference, somewhat higher distress and their believe in self-management is declined. This typology is an attempt to make the present data ®t in the framework of stages of readiness to change as proposed by Prochaska et al. (1992a,b) and it must be regarded as tentative, especially given the low proportion of patients in the precontemplation group. The ®rst limitation of the present study concerns the recruitment procedure which may have led to a selective sample of patients. For example, patients who were not interested in the treatment of pain may not have returned their questionnaire. This might explain the low percentage of precontemplators in the present sample and it may have restricted the variance of some variables of interest, thereby
lowering the possibility to ®nd signi®cant correlations. With regard to the socio-demographic characteristics, such as gender, age and marital status, however, the present sample was similar to other Dutch samples that were recruited randomly among patients that visited the hospital because of their complaints or from rheumatologists' ®les (De Blecourt and Knipping, 1995). Because ®bromyalgia is more prevalent in women and the present sample consisted of over 90% females, the present data may not be generalized to male patients. Secondly, the present cross-sectional data are mute about the factors that cause patients to move from one stage to the next. Lastly, because few data on readiness to change in pain patients are available, the present study was highly explorative in nature. Therefore, we did not correct for possible Type I error caused by multiple testing. In conclusion, the present data on the reliability and validity of the three scales indicate that the Contemplation scale had satisfactory psychometric properties but that the Precontemplation and Action scales need improvement. Although the validation of two scales was only partly satisfactory, the classi®cation of individual ®bromyalgic patients into groups on the basis of the scores on the three scales revealed potentially relevant psychological differences. The present study was a ®rst explorative attempt to study the concept of Readiness to change in ®bromyalgia patients. In future studies, the validity of the scales will have to be further improved and tested prospectively. Moreover, the theoretical basis of the construct of Readiness to change needs to be developed further. That is, hypotheses could be generated on appropriate concurrent validation measures and on scale-speci®c concurrent validation measures. Acknowledgements We thank the patient union Fybromialgia Eendrachtig Sterk and Debbie Tromp. References Bergin AE, Gar®eld SL. Handbook of psychotherapy and behavior change, New York: Wiley, 1994. Block AR, Kremer EF, Gaylor M. Behavioral treatment of chronic pain: the spouse as a discriminative cue for pain behavior. Pain 1981;9:243±252. Borkovec TD, Nau SD. Credibility of analogue therapy rationales. J Behav Ther Exp Psychol 1972;3:257±260. Budd RJ, Rollnick S. The structure of the Readiness to Change Questionaire: a test of Prochaska & DiClemente's transtheoretical model. Br J Health Psychol 1996;1:365±376. Davidson R. Prochaska and DiClemente's model of change: a case study? Br J Addict 1992;87:821±822. De Blecourt ACE, Knipping AA. Fibromyalgia: Towards an integration of somatic and psychological aspects. Doctoral dissertation, Groningen University: The Netherlands, 1995. Dijkstra A, De Vries H, Roijackers J, Breukelen, van G. Tailored interventions to communicate stage-matched information to smokers in different motivational stages. J Consult Clin Psychol 1998;66:549±557. Flor H, Kerns RD, Turk DC. The role of spouse reinforcement, perceived
A. Dijkstra et al. / Pain 90 (2001) 37±45 pain, and activity levels of chronic pain patients. J Psychosom Res 1987;31:251±259. Heather N, Rollnick S, Bell A. Predictive validity of the Readiness to Change Questionnaire. Addiction 1993;88:1667±1677. Keefe FJ, Caldwell DS. Cognitive behavioral control of arthritus pain. Med Clin North Am 1997;81:277±290. Keefe FJ, LeFebvre JC, Kerns RD, Rosenberg R, Beaupre P, Prochaska J, Prochaska JO, Caldwell DS. Understanding the adoption of arthritis self-management: stages of change pro®les among arthritis patients. Pain 2000;87:303±313. Kerns DK, Rosenberg R. Predicting responses to self-management treatments for chronic pain: application of the pain stages of change model. Pain 2000;84:49±55. Kerns DK, Rosenberg R, Jamison RN, Caudill MA, Haythornthwaite J. Readiness to adopt a self-management approach to chronic pain: the Pain Stages of Change Questionnaire (PSOCQ). Pain 1997;72:227±234. Lousberg R, Van Breukelen GJP, Groenman NH, Smidt AJM, Arntz A, Winter FAM. Psychometric properties of the Multidimensional Pain Inventory: Dutch language version (MPI-DLV). Behav Res Ther 1999;37:167±182. McConnaughy EA, Prochaska JO, Velicer WF. Stages of change in psychotherapy: measurement and sample pro®les. Psychother: Theory Res Pract 1983;20:368±375. McConnaughy EA, DiClemente CC, Prochaska JO, Velicer WF. Stages of change in psychotherapy: a follow-up report. Psychotherapy 1989;26:494±503. Miller WR, Rollnick S. Motivational interviewing, New York: The Guilford Press, 1991. Morley S, Eccleston C, Williams A. Systematic review and meta-analysis of randomized controlled trials of cognitive behaviour therapy and behaviour therapy for chronic pain in adults, excluding headache. Pain 1999;80:1±13. Nielson WR, Walker C, McCain GA. Cognitive behavioral group treatment of ®bromyalgia syndrome: preliminary ®ndings. J Rheum 1992;19:98± 103.
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Nielson WR, Vlaeyen JWS. The Pain Stages of Change Questionnaire, Ongepubliceerde vragenlijst, 1996. Prochaska JO. Systems of psychotherapy: a transtheoretical analysis. Homewood, IL: Dorsey Press 1984. Prochaska JO, DiClemente CC. Stages and processes of self-change of smoking: toward an integrative model of change. J Consult Clin Psychol 1983;51:390±395. Prochaska JO, Prochaska JM. Why don't continents move? Why don't people change? J Psychother Integration 1999;90(1):83±102. Prochaska JO, DiClemente CC, Norcross JC. In search of how people change, applications to addictive behaviors. Am Psychol 1992a;47: 1102±1114. Prochaska JO, DiClemente CC, Velicer WF, Rossi JS. Comments on Davidson's `Prochaska and DiClemente's model of change: a case study?' Br J Addict 1992b;87:825±828. Rollnick S, Heather N, Gold R, Hall W. Development of a short `Readiness to Change' questionnaire for use in brief, opportunistic interventions among excessive drinkers. Br J Addict 1992;87:743±754. Treasure JL, Katzman M, Schmidt U, Troop N, Todd G, de Silva P. Engagement and outcome in the treatment of bulimia nervosa: ®rst phase of a sequential design comparing motivation enhancement therapy and cognitive behavioural therapy. Behav Res Ther 1999;37:405± 418. Turk DC, Meichenbaum DH, Genest M. Pain and behavioral medicine: a cognitive behavioral perspective, New York: Guilford Press, 1983. Vlaeyen JWS, Teeken-Gruben NJG, Goossens MEJB, Rutten-van Molken MPMH, Eek H, van, Pelt RAGB, Heuts PHTG. Cognitive-educational treatment of ®bromyalgia, a randomized clinical trial. Part I. Clinical effects. J Rheum 1996;23:1237±1245. Weinman J, Petrie KJ, Moss-Morris R, Horne R. The Illness perception questionnaire: a new method for assessing the cognitive representation of illness. Psychol Health 1996;11:431±445. Wilson M, Bell-Dolan D, Beitman B. Application of the Stages of Change Scale in a clinical drug trial. J Anxiety Disorder 1997;11(4):395±408.
www.elsevier.nl/locate/pain
Readiness to adopt the self-management approach to cope with chronic pain in ®bromyalgic patients Arie Dijkstra a,*, Johan W.S. Vlaeyen b, Heidi Rijnen c, Warren Nielson d a
Department of Clinical and Health Psychology, Leiden University, P.O. Box 9555, 2300 RB, Leiden, The Netherlands b Department of Medical, Clinical and Experimental Psychology, Maastricht University, Maastricht, The Netherlands c Pulmonary Rehabilitation Centre, Hornerheide, The Netherlands d Arthritis Care Centre, London, Ontarion, Canada Received 1 March 2000; received in revised form 7 July 2000; accepted 17 July 2000
Abstract The effectiveness of cognitive-behavior therapy aimed at helping patients with the acquisition of self-management skills to cope with pain, is thought to depend partly on the patients' willingness to adopt a self-management approach. Some patients may not believe that selfmanagement will be helpful while others have decided to adopt it and others already apply the self-management skills in their daily lives. The present study explored the concept of `Readiness to change' in a population of Dutch ®bromyalgic patients. A self-report questionnaire was completed by 321 patients. Factor analysis revealed three scales, each assessing the characteristic of one stage of readiness to change, the Precontemplation, Contemplation and Action scale. Firstly, the reliabilities of these scales were 0.61, 0.86 and 0.61, respectively, and only the latter two scales correlated signi®cantly (r 0:14). Secondly, the scales were validated using subscales from the Multidimensional Pain Inventory, beliefs on the credibility of the self-management approach and subscales from the Illness Perception Questionnaire. These subscales explained 5, 22 and 8% of the variance of the scores on the Precontemplation, Contemplation and the Action scales, respectively. Thirdly, on the basis of the three scale scores, over 80% of the ®bromialgia patients could be classi®ed into one of ®ve potentially psychological relevant subgroups: Precontemplation, Contemplation, Preparation, Action and Relapse. The data suggest that improvements in operationalizations of the Precontemplation and Action dimensions of readiness to change are needed and that the theoretical foundation of readiness to change needs further development. q 2001 International Association for the Study of Pain. Published by Elsevier Science B.V. All rights reserved. Keywords: Self-management approach; Coping; Chronic pain; Cognitive-behavior therapy; Readiness to change
1. Introduction Besides the medical approach to treat chronic pain, psychological interventions may be applied to manage pain and its negative psychological and social consequences. The effectiveness of cognitive-behavior therapies with regard to coping with pain has been investigated and veri®ed in several studies (Turk et al., 1983; Nielson et al., 1992; Vlaeyen et al., 1996; Morley et al., 1999). In these therapies, patients may learn behavioral and cognitive self-management skills to cope with pain. The effectiveness of cognitive-behavior therapy depends on several therapist, treatment and patient characteristics (Bergin and Gar®eld, 1994). The patients' willingness to adopt the cognitive-behavioral approach is one example of a patient characteristic that determines effectiveness (Prochaska et al., 1992a). That is, when patients are * Corresponding author. Tel.: 131-71-527-4036; fax: 131-71-527-3619. E-mail address: [email protected] (A. Dijkstra).
not really convinced that self-management can be bene®cial, they may adhere to it as long as they are in therapy but they will be prone to relapse. This patient characteristic of willingness to adopt a certain new behavior is conceptualized as `readiness to change' (McConnaughy et al., 1983, 1989; Prochaska, 1984). Readiness to change refers to behavior change as a process instead of a discrete event: People move from no intention or motivation to change to the internalization of the new behavior. Several stages of readiness to change have been de®ned (Prochaska et al., 1992a). The ®rst stage is the precontemplation stage in which patients have not yet adopted the new behavior and are not motivated to change their behavior. According to Prochaska and DiClemente (1983), precontemplators: `¼tend be defensive and avoid changing their thinking and behavior¼' (p. 391). The second stage is the contemplation stage in which patients have not yet adopted the new behavior but think about chan-
0304-3959/01/$20.00 q 2001 International Association for the Study of Pain. Published by Elsevier Science B.V. All rights reserved. PII: S 0304-395 9(00)00384-5
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ging. However, they have not yet made a commitment to take action. The third and more recently added stage is the preparation stage in which people are planning to engage in the new behavior on the short-term. They have made a commitment to do so and they may already experiment or engage partly in the new behavior. The fourth stage is the action stage in which people execute the new behavior. However, this still costs a lot of energy. The ®fth stage is the maintenance stage: `¼in which people work to prevent relapse and consolidate the gains attained during action.' (p. 1104; Prochaska et al., 1992a). In earlier versions of the model the relapse stage was recognized but later removed from the model because it was not considered to be a stage but a regression to a former stage (Davidson, 1992; Prochaska et al., 1992b). Stages of readiness to change have been assessed in the change process in different populations, such as clinical (McConnaughy et al., 1989) and non-clinical populations (Prochaska et al., 1992a,b) and in different behaviors, such as excessive drinking (Rollnick et al., 1992; Budd and Rollnick, 1996) and weight control (Prochaska et al., 1992a). These studies used continuous readiness to change scales based on the original Readiness to Change Questionnaire of McConnaughy et al. (1983). This 32-item measure distinguishes between four stages of readiness to change, not including the newer preparation stage (Prochaska et al., 1992a; McConnaughy et al., 1989), whereas the 12-item measure distinguishes between three stages, not including the preparation and maintenance stage (Rollnick et al., 1992; Heather et al., 1993). Using these quantitative measures, people score higher or lower on characteristics of each stage. Readiness to change is expected to predict successful behavior change. That is, more people with high readiness to change are expected to change their behavior successfully compared to people with low readiness to change. Predictive validity of the stages might imply that to increase the effectiveness of the behavior therapy, the patients' readiness to change should be increased. Furthermore, it might implicate that patients in different stages of readiness to change may need stage-matched therapies (Dijkstra et al., 1998). However, the data on predictive validity from studies classifying patients on the basis of quantitative Readiness to change measures are disappointing (Heather et al., 1993; Treasure et al., 1999; Wilson et al., 1997), suggesting that there is a need for more valid measures of stages of readiness to change. No data are available with regard to the readiness to adopt a behavioral approach in patients with the ®bromyalgic syndrome. Individual ®bromyalgic patients might differ with regard to: (1) the extent that they belief that selfmanagement will bene®t them (precontemplation dimension); (2) the extent that they have a need for information on self-management of their pain (contemplation dimension); (3) the extent to which they already engage in selfmanagement (action and maintenance dimension). The
Readiness to change theory predicts that these characteristics of individual patients will be associated with drop-out and treatment success and that on the basis of the scores on these characteristics patients can be matched to treatments, for example, to a motivation-oriented or an action-oriented treatment. To the best of our knowledge, only three studies investigated the readiness to change concept in pain patients (Keefe and Caldwell, 1997, 2000; Kerns and Rosenberg, 2000). Kerns et al. (1997) identi®ed four scales with moderate to good reliability ± the precontemplation, the contemplation, the action and the maintenance scales ± using a 30item Readiness to change questionnaire in a sample of patients with chronic pain. The four scales showed interpretable relations with several criterion variables. For example, the precontemplation scale had a positive relation to patients' belief in medical pain treatment and a negative relation to patients' belief in the extent to which they can exert personal control over their pain. In a later study, Kerns and Rosenberg (2000) found that pretest scores on the precontemplation and contemplation scales predicted whether or not patients engaged in a self-management treatment for their chronic pain. Among patients who did engage in the self-management treatment, however, the Readiness to change scores were not related to treatment outcomes. Furthermore, decreases in precontemplation scores and increases in action and maintenance scores were related to decreases in pain intensity, disability and affective distress. These data provide preliminary support for the predictive validity and utility of a 30-item Readiness to change questionnaire regarding self-management of chronic pain. Keefe et al. (2000) assessed readiness to change in a sample of arthritis patients. Using cluster analyses they were able to identify ®ve clusters of patients with different con®gurations of scores on the precontemplation, the contemplation, the action and the maintenance scale. The ®rst three clusters clearly referred to the precontemplation stage (high on precontemplation and lower on the other scales), the contemplation stage (high on contemplation and lower on the other scales), the preparation stage (high on contemplation and action and lower on the other scales). The two additional clusters referred to patients in the action and the maintenance stage although these patients also scored higher on some other scales. The authors conclude that they were able to identify ®ve distinct subgroups that are consistent with the theoretical model. The goal of the present study was to explore the psychometric properties and the concurrent validity of a Dutch version of a questionnaire assessing readiness to change in a sample of patients with ®bromyalgia. First, the scale development will be described. On the basis of earlier studies (Kerns et al., 1997; McConnaughy et al., 1989) it is expected that at least three reliable scales ± each referring to another stage of readiness to change ± can be distinguished: the Precontemplation scale, the Contemplation scale and the Action scale. On the basis of the assumption that the three scales refer to one underlying dimension of
A. Dijkstra et al. / Pain 90 (2001) 37±45
readiness to change, it is expected that the scales will correlate signi®cantly (Rollnick et al., 1992). Second, the concurrent validity of the resulting scales will be studied by relating the Readiness to change measures to the validated Dutch version of the Multidimensional Pain Inventory (MPI; Lousberg et al., 1999), to beliefs on the credibility of the self-management of pain and the medical management of pain (CPT) and to the Illness Perception Questionnaire (IPQ; Weinman et al., 1996). It is expected that these measures will be related meaningfully to the three Readiness to change scales, in that they can be interpreted as being causes or effects of the patients' readiness to change. Stage classi®cation may serve the practical function of assessing patients' readiness to change before enrolment in cognitive-behavior therapy. Therefore, third, individuals will be classi®ed into one stage on the basis of the three Readiness to change scale scores and an attempt will be made to offer a psychological typology of patients in each stage using the variables from the validation tests. 2. Method 2.1. Recruitment and participant characteristics Participants were recruited from the Dutch Society of Fibromyalgic Patients. From the 9200 members, 745 patients were randomly selected using a computerized random number generator. These patients were subsequently sent the questionnaire, a pre-paid return and an accompanying letter explaining the procedure, the utility and conditions of the study. From the 745 patients who received a questionnaire, 339 (45.5%) questionnaires were returned of which 321 were ®lled in completely and were used in the present study. Most participants were female (92%), the average age was 48 years, and on average patients had suffered from pain for 16 years. Sixty percent had a low education level, which, in the diverse Dutch schooling system, refers to the level of vocational training. Furthermore, 74% were married, 5% were widowed, 8% were divorced and 12% were unmarried. Forty percent of the participants received disability compensation. 2.2. Questionnaire The questionnaire assessed several physical and psychosocial constructs. Only the questions and scales relevant for the present study will be presented here. 2.2.1. The stages of Readiness to change measure (SRC) First, 32 items for the Readiness to change measure were derived from an unpublished English Readiness to Change Questionnaire (Nielson and Vlaeyen, 1996) which had been based on McConnaughy et al.'s (1989) measure of readiness to change. The items were adapted for use with chronic pain patients and they referred to readiness to adopt a selfmanagement approach to cope with pain. The characteris-
39
tics of four stages of readiness to change were assessed each with eight items. A high score on an item such as: `I don't think I need to change the ways I manage my pain', was considered to be indicative of the precontemplation stage. A high score on an item such as: `I would like to have more ways to manage my pain', was considered to be indicative of the contemplation stage. A high score on an item such as: `I am working hard to manage my pain', was considered to be indicative of the action stage. A high score on an item such as: `I now need support to keep managing my pain', was considered to be indicative of the maintenance stage. The items could be scored from `I do not agree at all' (22) to `I totally agree' (12). Second, after translation in Dutch the face validity of the items was assessed by asking eight researchers with thorough knowledge of the readiness to change concept from the Department of Health Education to categorize each of the 32 items to one particular stage of readiness to change. The items meant to assess the precontemplation stage, the contemplation stage and the action stage were all interpreted according to expectations. However, six of the eight items assessing the maintenance stage were wrongly classi®ed by several experts from the Department of Health Education. Most of the time the items were mistakenly categorized as items assessing the precontemplation stage. Looking more closely at the maintenance items it seemed they all referred to an impending danger of relapse. It might be concluded that the maintenance items were classi®ed as precontemplation items because of a similar underlying dimension of low motivation or a lack of con®dence in the ability to change the behavior (McConnaughy et al., 1989). Thus, the maintenance items were removed from the questionnaire leaving 24 items assessing the precontemplation stage, the contemplation stage and the action stage. 2.2.2. The Multidimensional Pain Inventory (MPI) This inventory assesses several aspects of the impact of pain in patients' lives. The Dutch version of this questionnaire, containing nine subscales, is validated and has proven to have good internal consistency and test-retest reliability (Lousberg et al., 1999). The following scales were distinguished: Pain intensity (two items; Cronbach's alpha (a ) 0.88), Interference (nine items; a 0.82), Life control (three items; a 0.84), Affective distress (three items; a 0.77), Social support (three items; a 0.87), Punishing responses (three items; a 0.85), Solicitous responses (six items; a 0.73), Distracting responses (three items; a 0.61) and General activity (18 items; a 0.70). The item anchors were item-speci®c. For example, a question about the extent of the experienced pain could be scored from `no pain at all' (0) to `a great deal of pain' (6), while a question on control could be scored from `no control' (0) to `a great deal of control' (6). 2.2.3. Credibility of pain treatments (CPT) In order to assess to what extent Readiness to change was
40
A. Dijkstra et al. / Pain 90 (2001) 37±45
associated with beliefs about the credibility of medical and behavioral treatments, participants read a short description of a medical and a behavioral pain treatment. They then were asked two questions with regard to each pain treatment: `Do you think this treatment would be effective; (1) for you; (2) for others'. The items could be scored on a Visual Analogue Scale from: `not effective at all' to `very effective' (based on Borkovec and Nau (1972)). 2.2.4. Illness Perception Questionnaire The Illness Perception Questionnaire (IPQ; Weinman et al., 1996) assesses the attributions patients make with regard to the causes of (ten items) and in¯uences on (ten items) their pain. Four subscales were formed. Two scales assessed the perceived biological causes (®ve items; a 0.65) and the perceived biological in¯uences (®ve items; a 0.64). The items referred to nutritional, genetic, viral, environmental and medical causes of or in¯uences on the pain complaints. Furthermore, two scales assessed the perceived psychosocial causes (four items; a 0.77) and the perceived psychosocial in¯uences (four items; a 0.81). The items referred to life-style, stress, other people and mental condition as causes of or in¯uences on the pain complaints. One item, on `chance' as a cause or in¯uence, was removed because it lowered the reliability of both psychosocial scales. The items could be scored from:'I do not agree at all' (1) to `I totally agree' (5). 3. Results 3.1. Scale development A Principal Component Analyses was conducted on the 24 items assessing readiness to change. The number and
quality of the components was determined by: (a) the interpretability of the proposed components; (b) the extent to which an item loaded uniquely on the expected component; (c) the changes in explained variance of the components. Furthermore, the internal consistency (Cronbach's a ) was assessed to learn to what extent the items in one scale referred to the same underlying factor. Using these criteria, another six items were removed. Table 1 shows the remaining items and their factor loadings. The Precontemplation scale was composed of ®ve items, with an average inter-item correlation of 0.25 and a 0.63. The Contemplation scale was composed of seven items, with an average inter-item correlation of 0.46 and a 0.86. The Action scale was composed of six items, with an average inter-item correlation of 0.21 and a 0.61. The internal consistencies of the precontemplation and the action scales were moderate but suf®cient in the present developmental phase. The correlations among the three scales were computed: Only the contemplation and action scale correlated signi®cantly but low (r 0:14). 3.2. Concurrent validity To investigate the concurrent validity of the three Readiness to change measures, the scale scores were predicted by the MPI scales, the CPT beliefs and the IPQ scales, using three multivariate regression analyses (Table 2). The independent variables were entered in blocks: (1) demographics (age, level of education, gender and living conditions); (2) motivating factors (pain intensity, interference and distress); (3) social in¯uence (support, punishing and solicitous responses, distraction); (4) control and attribution (the IPQ scales, control, activity); (5) CPT beliefs. The data on the prediction of the Precontemplation scores
Table 1 Items and factor loadings of the three factors that each comprise a Readiness to change scale a Precontemplation I do have problems in coping with my pain, but many people do. Why should I elaborate on that? I would rather leave the situation as it is, than start searching for alternatives. Why should I change? Let the doctor take care of my pain. All that talking about psychology and my pain bores me. Why don't people just act normal. I don't have to change my way of coping with the pain because my coping has nothing to do with it. I really think I should change the way I cope with my pain. It would be worthwhile to be able to in¯uence my pain myself. I wish I had some more ways to cope with my pain. Skills to in¯uence my pain myself could be helpful for me. I wish that someone had some good advice for me so that I would suffer somewhat less from my pain. I have been thinking for a while that I would like to learn to cope differently with my pain. I hope I could get some more insight into my pain. I am actively trying to ®nd ways to cope with my pain differently. It is easy to talk about coping differently with your pain but I am, at least, doing it differently. Although my pain still in¯uences my life negatively, I keep on trying to in¯uence the pain myself. I often feel limited by my pain but I am working on it. I do things to in¯uence my pain. I am working hard to get the pain under my control. a
All loadings .0.40 are depicted.
0.68 0.56 0.45 0.72 0.61
Contemplation
0.76 0.58 0.82 0.67 0.77 0.76 0.71
Action
0.60 0.60 0.41 0.57 0.45 0.75
A. Dijkstra et al. / Pain 90 (2001) 37±45 Table 2 Multivariate regression analyses with the Readiness to change scales as dependent variables and the demographic variables, the MPI scales, the CPT scales and the IPQ scales as predictors a Beta
Cumulative adjusted R 2
Precontemplation Education Age Will self-management of pain help you?
20.24*** 0.19** 20.21***
0.09 0.11 0.16
Contemplation Distress Interference Biological in¯uences Will self-management of pain help you?
0.32*** 0.18** 0.15** 0.12*
0.15 0.19 0.21 0.22
Action Age Interference Distraction Control Will self-management of pain help others?
0.18** 0.17** 0.14* 0.11 ² 0.19**
0.02 0.04 0.05 0.07 0.10
a ²
P , 0:10; *P , 0:05; **P , 0:01; ***P , 0:001. In three multivariate regression analyses, the Readiness to change scale scores were predicted by the independent variables that were entered in blocks: (1) demographics (age, level of education, gender and living conditions); (2) MPI motivating factors (pain intensity, interference and distress); (3) MPI social in¯uence (support, punishing and solicitous responses, distraction); (4) MPI control and IPQ attribution (control, activity and IPQ-scales); (5) CPT beliefs.
revealed that level of education, age and the credibility of the self-management approach for the patient him/her self were signi®cant predictors, explaining 16% of its variance. The data on the prediction of the Contemplation scores revealed that levels of distress and interference and beliefs on the biological in¯uences and credibility of the selfmanagement approach were signi®cant predictors, explaining 22% of its variance. The data on the prediction of the Action scores revealed that age, levels of interference, distraction, control and the credibility of the self-management approach were signi®cant predictors, however, explaining only 10% of its variance.
41
stage. In this way patients could be classi®ed in the precontemplation stage (1; 2 ; 2 ) the contemplation stage (2; 1 ; 2 ); or in the action stage (2; 2 ; 1 ). In addition, patients with a low score on the precontemplation scale in combination with high scores on the contemplation and action scales (2; 1 ; 1 ) were considered to be in the preparation stage (Heather et al., 1993). These patients are considered to have characteristics of both adjacent stages. Finally, patients with a high score on precontemplation, a low score on contemplation but a high score on action (1; 2 ; 1 ) were considered to be in danger of relapse. Table 3shows frequencies and percentages of patients that could be classi®ed in one stage. Using the original three stage model, only 29.3% of the patients were in one particular stage. Adding the preparation stage, the percentage of classi®able patients increased to 78.5%. Recognizing patients in danger of relapse, the percentage increased to 83.5%. The remaining 16.4% patients were designated `unclassi®able'. 3.4. Stage typology Figs. 1 and 2 show the mean scores on the MPI, the CPT and the IPQ scales of the six groups of ®bromyalgia patients: patients in the precontemplation stage, the contemplation stage, the preparation stage and the action stage and patients who are in danger of relapse and the unclassi®able groups. The groups were compared to each other using analysis of variance. First of all, the groups of patients were compared on the MPI scales. 3.4.1. MPI impact The groups differed signi®cantly on the experienced pain (P , 0:001), the interference of pain (P , 0:001) and level of distress (P , 0:001). The upper graph in Fig. 1 (MPI impact factors) shows that precontemplators have about the same levels of pain and interference as contemplators and preparers but that they have a more positive mood (score lower on distress). Patients in action seem to be Table 3 Classi®cation of patients in one stage group using positive (1) and neutral or negative (2) scores on the three scales a
3.3. Classifying patients into one stage
Stage groups
Pc/C/Act-scales
Frequency
Percentage
For clinical purposes it may be bene®cial to be able to classify patients into one discrete stage. That is, people could then be considered to be in the precontemplation, the contemplation stage or the action stage. In line with Rollnick et al. (1992); Heather et al. (1993), the present average scale scores, ranging from 22 to 12, were used: When a patient had a score of zero or lower than zero on a scale, the patient was considered to not have the characteristic measured by that speci®c scale. Thus, a patient who scored .0 on the precontemplation scale but #0 on both other scales was considered to be in the precontemplation
Precontemplators Contemplation Preparation Action Relapse Unclassi®able 1 Unclassi®able 2 Unclassi®able 3
122 212 211 221 121 112 111 222
4 22 158 68 16 3 38 12
1.2 6.9 49.2 21.2 5 0.9 11.8 3.7
a Pc, Precontemplation scale; C, Contemplation scale; Act, Action scale. Plus (1) means that the score on the particular scale is higher than zero. Minus (2) means that the score on the particular scale is equal or lower than zero.
42
A. Dijkstra et al. / Pain 90 (2001) 37±45
and borderline signi®cantly on activity (P , 0:10). The lower graph in Fig. 1 (MPI control and activity) shows that precontemplators experience more control than patients in contemplation and preparation, while patients in action score the highest. With regard to the MPI scale `general activity', especially contemplators score high (even somewhat higher than those in action) and preparers score low. Patients in danger of relapse and the unclassi®able groups scored moderate. 3.4.4. CPT scales The groups only differed borderline signi®cantly on the belief that self-management of pain is an effective means to cope with pain (P , 0:10). The upper graph in Fig. 2 (CPT scales) shows that precontemplators scored the lowest, contemplators, preparers and patients in action scored higher while patients who are in danger of relapse, again, scored lower. 3.4.5. IPQ scales The groups only differed borderline signi®cantly on the psycho-social causes and signi®cantly on psycho-social in¯uences (P , 0:10 and P , 0:05, respectively). The lower graph in Fig. 2 (IPQ scales) shows that precontemplators scored lower than the other patient groups. Fig. 1. The scores on the MPI subscales for patients in each stage group in standardized T-scores (mean 50; Standard Deviation 10). Pc, precontemplation; C, Contemplation; Pr, Preparation; Act, Action; Rel, prone to Relapse; Uncl, Unclassi®able. ***P , 0:001 (vertical); **P , 0:05 (vertical); *P , 0:10. Signi®cance's are of the overall F-test comparing all six groups of patients.
able to decrease the pain and interference and they also have more positive mood. In patients who are in danger of relapse and patients in the disengaged group things seem to be worse again. 3.4.2. MPI social in¯uence The groups differed borderline signi®cantly on social punishment (P , 0:10) and signi®cantly on social support (P , 0:05). The middle graph in Fig. 1 (MPI social in¯uence) shows that precontemplators perceive fewer punishing and distracting social in¯uences than patients in contemplation and preparation and more supporting and solicitous in¯uences than patients in contemplation and preparation. In particular contemplators perceive many punishing and few supporting social in¯uences. In the remaining groups few differences seem present although the low perceived support of patients who are in danger of relapse is striking. 3.4.3. MPI control and activity The groups differed signi®cantly on control (P , 0:001)
Fig. 2. The scores on the credibility beliefs and the IPQ attribution subscales for patients in each stage group. Upper graph in standardized T-scores (mean 50; Standard Deviation 10). Pc, precontemplation; C, Contemplation; Pr, Preparation; Act, Action; Rel, prone to Relapse; Uncl, Unclassi®able. ***P , 0:001 (vertical); **P , 0:05 (vertical); *P , 0:10. Signi®cance's are of the overall F-test comparing all six groups of patients.
A. Dijkstra et al. / Pain 90 (2001) 37±45
4. Discussion The goal of the present study was to explore the psychometric properties and the validity of a Dutch version of the Readiness to change questionnaire in a sample of patients with fybromyalgia. The three scales were considered to asses the readiness to change the way to cope with the pain. The reliability of the Contemplation scale was 0.86 and the reliabilities of the Precontemplation and the Action scales were just above 0.60, thereby threatening the validity of both measures. The validity of these scales was further compromised by the ®nding that the variables used to assess the concurrent validity of the three scales explained 22% of the variance in the Contemplation scores, but only 5 and 8% of the Precontemplation and Action scores, respectively. Although the strength of the relations between the Readiness to change scales on the one hand and the concurrent validity measures on the other hand were only moderately to weak, the relations could be interpreted meaningfully. Patients' scores on the Precontemplation scale were related to the credibility of the self-management approach. Low credibility of the self-management solution can be regarded as one of the causes of low readiness to change (Prochaska and Prochaska, 2000). This interpretation is in line with the ®nding of Kerns et al. (1997) that the higher patients scored on the belief that their pain could be cured medically, the higher their scores on the Precontemplation scale. Patients' scores on the Contemplation scale, ®rst, were predicted by the level of distress and the extent to which the pain interfered with the normal life routine. Distress and interference may be viewed as motives to contemplate changing. This is in line with the conception of contemplators becoming motivated to change because they start to process information on the pros and cons of their current behavior (Prochaska et al., 1992a). Furthermore, the contemplation scores were higher as patients found the self-management approach more credible. The credibility may be viewed as a precondition to become motivated in the ®rst place. The ®nding that the biological attributions of complaints were a predictor of contemplation is a puzzling ®nding and in contrast with the ®ndings of Kerns et al. (1997). Our ®nding might be a sign that the more patients contemplate changing, the more they become to believe that at least a part of their complaints is hard to change because of biological roots. Patients' scores on the Action scale were predicted by interference, social distraction, experienced control and the credibility of self-management to help others. Interference, again, might be the motive to be active, while experiencing more control might be an effect of becoming more active. On the other hand, when patients start coping actively with their pain, the interference of pain with their lives might become more salient. Furthermore, the more active patients were, the more the spouse tried to distract the patient from the pain. Acknowledging the important in¯uence of the spouse on the pain (Block et al., 1981; Flor et al., 1987), this might mean that, both patient and spouses, become active. It might even mean that the readiness to adopt
43
a self-management approach is a function of the patient's family system. Lastly, the ®nding that the credibility of the self-management approach to help others was a predictor, might mean that the effects of the activities patients engage in fall somewhat short of their expectations but that they still see some potential bene®ts in the approach for others. In conclusion, the concurrent validity of the Precontemplation and Action scales left something to be desired. With regard to the relations among the three Readiness to change scales, several authors predicted that the three scales will correlate (Budd and Rollnick, 1996; Kerns et al., 1997; McConnaughy et al., 1983, 1989; Rollnick et al., 1992), thereby indicating an unitary underlying dimension of readiness to change. In the present study, however, only the Contemplation and Action scales correlated signi®cantly but low (r 0:14). Thus, the present data do not support the notion of a single underlying construct of readiness to change. Seemingly, a patient can think about adopting the self-management approach as measured by the Contemplation scale but still resist changing as measured by the Precontemplation scale. It might be that the Precontemplation scale is more a measure of temporary communicationinduced reactance or defensiveness instead of a measure of low readiness. Another explanation lies in a possible lack of clarity with regard to the behavior to which the items refer (also see Treasure et al., 1999). In studies on alcohol intake the behavior under study ± not drinking (McConnaughy et al., 1983, 1989; Rollnick et al., 1992) ± is more unequivocal. In the present study, we assessed the readiness to `change the way to cope with the pain'. This formulation may have been too broad. That is, we might expect that their is little consensus about ways to cope with pain among patients. One solution would be to focus the items on one speci®c and identi®able behavior, for example, `engaging in a short relaxation exercise'. The proportion of subjects that can be classi®ed in one stage ± on the basis of the con®guration of the three scale scores ± is another way to learn about the Readiness to change scales. Although only 29% of the patients could be classi®ed using the three stage model (Precontemplation, Contemplation and Action), the addition of the Preparation stage group increased the percentage of classi®able patients from 29.3 to 78.5%. Heather et al. (1993) report a similar ®nding of an increase of the percentage of classi®able people from 40 to 75% when they added the Preparation stage to their model. In the present sample of ®bromyalgia patients, almost 50% of the patients were in the Preparation, that is, they scored above zero on the Contemplation and the Action scales and below zero on the Precontemplation scale. In other words, those patients indicate that they are active in coping with their pain (doing something, being active, working on) but at the same time have a need for further change. It might be concluded that half of the ®bromyalgia patients sampled have not yet found a satisfactory level of coping with their pain. The present cross-sectional data can not be conclusive
44
A. Dijkstra et al. / Pain 90 (2001) 37±45
about whether patient move through psychological stages in a ®xed sequence. Therefore, at the best, the above classi®cation refers to subgroups of ®bromyalgia patients. On the basis of the scores on the MPI-, CPT- and IPQ-questionnaires, the following typology of patients in the different subgroups can be formed. Precontemplators seem to be stuck in a selfpreserving state: Despite high levels of pain and interference (even somewhat higher than patients in contemplation and preparation) they manage to keep their spirits up (low distress scores) and they have developed an illusion of control. This interpretation is in line with the notion that people in the precontemplation stage are defensive to potential changemotivating information (Miller and Rollnick, 1991; Prochaska and Prochaska, 2000). This psychological state is further protected by the perception of low credibility of the effectiveness of self-management and low psychosocial attributions. Lastly, the social in¯uence seems to further reinforce this state with high levels of support and solicitous responses and low levels of punishing and distracting responses. This description seems in line with the ®nding of Kerns et al. (1997) that higher Precontemplation scores were related to a measure of wishful thinking and dependency on others. In contrast, contemplators seem to be in an unstable state: High levels of interference, high distress, low levels of control and they do believe that self-management could help and that their pain is partly in¯uenced by psychosocial factors. Whereas precontemplators' situation seems socially reinforced, contemplators report high levels of punishing responses of the spouse and low levels of support. Patients in the preparation group were very similar to those in the contemplation group. However, they report renewed, and maybe qualitatively different, social support and they score lower on activity. Patients in the preparation group seem to engage less in normal daily activities. Given the items anchors, from never doing this to doing this very often, the low activity score might indicate that those patients are painfully aware of the limitations they have. Patients in the action group show that coping actively with their pain helps: They speci®cally report lower levels of pain and interference, lower distress and more control. They believe that self-management also can help others, probably because they experience it themselves. Patients who are active but in danger of relapse report lower social support and more pain, interference, somewhat higher distress and their believe in self-management is declined. This typology is an attempt to make the present data ®t in the framework of stages of readiness to change as proposed by Prochaska et al. (1992a,b) and it must be regarded as tentative, especially given the low proportion of patients in the precontemplation group. The ®rst limitation of the present study concerns the recruitment procedure which may have led to a selective sample of patients. For example, patients who were not interested in the treatment of pain may not have returned their questionnaire. This might explain the low percentage of precontemplators in the present sample and it may have restricted the variance of some variables of interest, thereby
lowering the possibility to ®nd signi®cant correlations. With regard to the socio-demographic characteristics, such as gender, age and marital status, however, the present sample was similar to other Dutch samples that were recruited randomly among patients that visited the hospital because of their complaints or from rheumatologists' ®les (De Blecourt and Knipping, 1995). Because ®bromyalgia is more prevalent in women and the present sample consisted of over 90% females, the present data may not be generalized to male patients. Secondly, the present cross-sectional data are mute about the factors that cause patients to move from one stage to the next. Lastly, because few data on readiness to change in pain patients are available, the present study was highly explorative in nature. Therefore, we did not correct for possible Type I error caused by multiple testing. In conclusion, the present data on the reliability and validity of the three scales indicate that the Contemplation scale had satisfactory psychometric properties but that the Precontemplation and Action scales need improvement. Although the validation of two scales was only partly satisfactory, the classi®cation of individual ®bromyalgic patients into groups on the basis of the scores on the three scales revealed potentially relevant psychological differences. The present study was a ®rst explorative attempt to study the concept of Readiness to change in ®bromyalgia patients. In future studies, the validity of the scales will have to be further improved and tested prospectively. Moreover, the theoretical basis of the construct of Readiness to change needs to be developed further. That is, hypotheses could be generated on appropriate concurrent validation measures and on scale-speci®c concurrent validation measures. Acknowledgements We thank the patient union Fybromialgia Eendrachtig Sterk and Debbie Tromp. References Bergin AE, Gar®eld SL. Handbook of psychotherapy and behavior change, New York: Wiley, 1994. Block AR, Kremer EF, Gaylor M. Behavioral treatment of chronic pain: the spouse as a discriminative cue for pain behavior. Pain 1981;9:243±252. Borkovec TD, Nau SD. Credibility of analogue therapy rationales. J Behav Ther Exp Psychol 1972;3:257±260. Budd RJ, Rollnick S. The structure of the Readiness to Change Questionaire: a test of Prochaska & DiClemente's transtheoretical model. Br J Health Psychol 1996;1:365±376. Davidson R. Prochaska and DiClemente's model of change: a case study? Br J Addict 1992;87:821±822. De Blecourt ACE, Knipping AA. Fibromyalgia: Towards an integration of somatic and psychological aspects. Doctoral dissertation, Groningen University: The Netherlands, 1995. Dijkstra A, De Vries H, Roijackers J, Breukelen, van G. Tailored interventions to communicate stage-matched information to smokers in different motivational stages. J Consult Clin Psychol 1998;66:549±557. Flor H, Kerns RD, Turk DC. The role of spouse reinforcement, perceived
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