Learning from unreliability: the importance of inconsistency in coping dynamics

PERGAMON

Social Science & Medicine 48 (1999) 619±631

Learning from unreliability: the importance of inconsistency in coping dynamics Carolyn E. Schwartz a, b, *, Lawren H. Daltroy c, d a

Frontier Science and Technology Research Foundation, 1244 Boylston Street, Suite 303, Chestnut Hill, MA 02467, USA b Department of Psychiatry, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA c Multipurpose Arthritis and Musculoskeletal Diseases Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA d Department of Health and Social Behavior, Harvard School of Public Health, Boston, MA, USA

Abstract The role of response stability in the measurement of coping is examined with a focus on the unique information that can be gleaned from low test±retest reliability (`inconsistency'). Data from two studies are presented in which a card sort measure of coping ¯exibility was used on people with three di€erent chronic diseases and the elderly (n = 219). We begin by testing the hypothesis that the low stability re¯ects unreliability due to measurement artifacts, such as random error, low ecological validity, long test±retest interval, surrogate assistance, or error due to completing the questionnaire in multiple sittings. Our ®ndings suggest that surrogate assistance in completing questionnaires was the only measurement artifact associated with low stability. We then tested the proposition that low stability re¯ects a genuine behavior pattern (i.e. inconsistency). Hierarchical modeling revealed that measurement artifact accounted for less than one percent of the variance in inconsistency in reported coping behavior and that an additional 21% of the variance could be explained by the behavioral factors, including neuropsychological problems (9%), psychological morbidity (4%), locus of control (3%) and eudaimonistic well-being (5%). Thus inconsistency in reported coping behavior was better explained by behavioral and psychosocial factors than by the tested measurement artifacts. We conclude that inconsistency in reported coping behavior does indeed re¯ect a meaningful behavior pattern, rather than simply measurement artifact. # 1999 Elsevier Science Ltd. All rights reserved.

1. Introduction Nothing endures but change Heraclitus, ca. 540±ca. 480 B.C. The more things change, the more they remain the same Ahphonse Karr, 1808±1890. Traditional psychometrics suggests that a good measurement instrument must be reliable. However, when one is trying to measure constructs which are

* Corresponding author. Fax: +1-617-632-2001; e-mail: [email protected].

dynamic in nature, measurement reliability may be attained at the cost of losing other valuable information and may actually re¯ect an overly simplistic model of the relationships of interest. Thus, measurement stability may be encouraging when one attempts to measure qualities which are unlikely to change (e.g. personality traits), but discouraging when one attempts to observe and describe dynamic processes (Meehl, 1973). Coping is such a process, as it requires a dynamic responsiveness to situational challenges. This paper attempts to further our understanding of the role of response stability in the measurement of coping by examining the unique information that can be gleaned from low test±retest reliability in a coping measure.

0277-9536/99/$ - see front matter # 1999 Elsevier Science Ltd. All rights reserved. PII: S 0 2 7 7 - 9 5 3 6 ( 9 8 ) 0 0 3 5 3 - 0

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Investigators in the measurement of coping have approached the issue of psychometric reliability in a variety of fashions, depending on the theory driving their measure (see Aldwin, 1994 for helpful review). Trait measures of coping may use traditional test±retest indicators of reliability to support the validity of their measure since reliability is a necessary condition of validity for measures of stable (i.e. trait) characteristics (e.g. Miller, 1987; Watson et al., 1988; Amirkhan, 1990; Endler and Parker, 1990). In contrast, process measures of coping, such as the Ways of Coping Questionnaire (WCQ) (Folkman and Lazarus, 1988), may use other indices of reliability, but must apply traditional standards judiciously. The WCQ was founded on a transactional model which works on the premise that coping is a process which, by de®nition, is variable and is a function of the person±environment interaction (Folkman and Lazarus, 1985). Consequently, judgements about the reliability of the WCQ are not based on test±retest estimates. Applying other measures of reliability requires careful reconsideration of psychometric standards because standards derived from attitudinal measures are inappropriate to process measures (Folkman, 1992). As Stone and Kennedy-Moore (1992) have noted, coping subscales may list several alternative behaviors re¯ective of a particular strategy so it would be unnecessary to utilize more than one such strategy, a process which would lead to low internal consistency on the subscale measuring that strategy. Other approaches for assessing reliability might include evaluating the consistency of the factor structure across study populations; and the mean autocorrelation of subscales across stressful encounters (e.g. Folkman and Lazarus, 1988). The problem of unreliability presents a challenge to coping researchers because its meaning may re¯ect personality traits, developmental processes or meaningful aspects of the coping process. Self-esteem is an example of a relevant personality trait. People with low self-esteem have been found to exhibit less temporal stability and less internal consistency in rating their own traits than people with high self-esteem (Campbell, 1990). However, the impact of self-esteem on depression seems to be moderated by the stability of self-esteem (Kernis et al., 1991), suggesting that it is the consistency of high levels of this personality characteristic that seems to be protective from psychological morbidity. Since personality consistency is distinct from behavioral consistency, people may respond to contextual changes by behaving di€erently while preserving distinctive behavioral styles across situations (Funder and Colvin, 1991). Thus, coping behavior may change across situations but the e€ectiveness of a particular strategy may be mediated by the consistency of some unknown and relevant personality characteristic.

In the present paper, we explore the correlates of one aspect of inconsistency. A developmental process which may be relevant to measuring coping is related to self-awareness, a maturational aspect of emotional intelligence (Westenberg and Block, 1993). Knowles (1988) found that a personality test item's correlation with the rest of the items on the test increased linearly with its serial position (i.e. placement) in a test. Further, the answers of people with an internal locus of control became more polarized and less variable, as compared to people with an external locus of control (Knowles, 1988). Hamilton and Shuminsky (1990) found that heightened self-awareness reduced inconsistency in test responses, suggesting that the decreased variability later in a test was due to the activation of a general self-schema. Similarly, Nasby (1989) found that individuals high in private self-consciousness had articulated self-schemata of greater temporal stability than individuals low in private self-consciousness. Thus, inconsistency in self-report may re¯ect an incomplete or inadequate understanding of oneself and an expectancy that reward is not contingent on one's own behavior (i.e. an external locus of control). This process may have implications for how much an individual can learn from ine€ective coping strategies. If coping is a trial-and-error process, then individuals with low levels of self-awareness may be ill-equipped to learn from their ine€ective coping e€orts. This handicap may be re¯ected by low reliability on coping measures. Low reliability may re¯ect other meaningful aspects of the coping process as well. For example, low levels of test±retest reliability on self-reports of coping tendencies may suggest that reported coping behavior is less stable than personality traits (Carver et al., 1989). Inconsistency in the factor structure of a coping measure may re¯ect items which are not applicable to the coping context (Stone et al., 1991; Parker et al., 1993; De Ridder, 1997) or that characteristics of serious illness change coping patterns (Aldwin, 1994). Finally, low internal consistency reliability on a coping measure might re¯ect the sequential nature of an individual's coping process, or that di€erent strategies were useful for di€erent aspects of the problem (Aldwin, 1994). The present work tests speci®c hypotheses to elucidate the meaning of low stability on a card sort measure of coping. It investigates whether inconsistency in reported coping behavior is a measurement artifact or whether it is systematically associated with behavioral and psychological problems, thereby re¯ecting a meaningful behavior pattern. We will refer to response instability in reported coping as `inconsistency' since it connotes a personality characteristic and because this work examines random rather than purposeful changes in coping behavior. Previous work

C.E. Schwartz, L.H. Daltroy / Social Science & Medicine 48 (1999) 619±631

621

2. Methods

from people with rheumatoid arthritis (RA) (n = 45), systemic lupus erythematosus (SLE) (n = 44) and the elderly (i.e. over 70 years of age) (n = 38). In the second study, data were collected by interview and by mail from 132 people with multiple sclerosis (MS). Participants in both studies were recruited from the patient registry of a large urban teaching hospital. Study participants tended to be middle-aged, married Caucasians with some college education (Table 1). There were more females than males in both studies, a gender distribution which re¯ects the fact that women are more likely to have RA, SLE, or MS (Masi and Medsger, 1979; Martyn, 1991) and to live longer (Nygaard et al., 1990). Disease duration was slightly longer for the chronically ill patients in study 1 as compared to those in study 2.

2.1. Subjects

2.2. Measures

We present data from two studies to test speci®c hypotheses about inconsistency in reported coping behavior. In the ®rst study, data were collected by mail

Standardized self-report measures were used in both studies, and study 2 also included some observerreported measures. Given the focus on replication,

done by our group demonstrated that variability in reported coping behavior was associated with health and suggested that this variability was purposeful, not random (Schwartz et al., 1998). In contrast, the present work examines inconsistencies in reported coping behavior over a short period of time (i.e. response style or response set), rather than temporal changes in observed (i.e. actual) coping behavior. We present data from two studies which used a card sort measure of coping ¯exibility, the Flex (Schwartz and Daltroy, 1991). This measure attempts to highlight the dynamic nature of coping by quantifying the impact of contextual changes on reported coping behavior.

Table 1 Demographic informationa Demographic variable

Rheumatoid arthritis (n = 45)

Systemic lupus erythematosus (n = 44)

Elderly (n = 38)

Multiple sclerosis (n = 132)

Mean age (SD) No. females (%) Education Graduate school Some college/college graduate High school or less Race Caucasian African±American Other Mean disease duration (S.D.) Marital status (%) Married Separated or divorced Widowed Never married Employment (%) Part/full time Disabled Retired Other Present/past occupation (%) Professional/managerial Clerical Laborer/service Housewife Income (median category) Range

55.3 (10.9) 23 (51%)

41.3 (6.2) 36 (82%)

79.3 (4.9) 18 (47%)

43.1 (9) 98 (74%)

5 (11%) 25 (56%) 15 (33%)

7 (16%) 21 (48%) 16 (36%)

14 (37%) 14 (37%) 10 (26%)

37 (29%) 73 (57%) 17 (13%)

40 (89%) 3 (7%) 2 (4%) 14.1 (9.3)

38 (86%) 3 (7%) 3 (7%) 13.8 (8.5)

38 (100%) 0 (0%) 0 (0%) NA

127 (96%) 3 (2%) 2 (<2%) 7.8 (6.4)

30 (67%) 7 (16%) 2 (4%) 6 (13%)

33 (77%) 5 (12%) 0 (0%) 5 (12%)

15 (40%) 1 (3%) 19 (50%) 3 (8%)

85 (64%) 18 (14%) 4 (3%) 25 (19%)

26 (58%) 5 (11%) 7 (16%) 7 (16%)

18 (41%) 8 (18%) 3 (7%) 15 (34%)

3 (8%) 0 (0%) 27 (71%) 8 (21%)

58 (44%) 42 (32%) 7 (5%) 25 (19%)

22 (49%) 7 (16%) 13 (29%) 3 (7%) $25,000±40,000 $5,000±65,000+

24 (55%) 9 (21%) 5 (11%) 6 (14%) $40,000±65,000 <$5,000±65,000+

21 (55%) 9 (24%) 1 (3%) 7 (18%) $40,000±65,000 <$5,000±65,000+

95 (72%) 23 (17%) 9 (7%) 5 (4%) $45,000 $5,000±75,000

NA = Not applicable.aNumbers may not sum to total n or to 100% due to rounding error.

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C.E. Schwartz, L.H. Daltroy / Social Science & Medicine 48 (1999) 619±631

there was some overlap in the constructs evaluated in the two studies, and study 2 contained measures of neuropsychological performance and eudaimonistic well-being to follow up on hypotheses generated from study 1 (Table 3 summarizes the measures used in both studies). 2.2.1. Constructs measured in both studies Functional problems were assessed in study 1 using the Arthritis Impact Measurement Scales (AIMS) (Meenan et al., 1980; Meenan, 1982; Hughes et al., 1991) and in study 2 using the Sickness Impact Pro®le (Bergner et al., 1976; Pollard et al., 1976; Bergner et al., 1981). Neurologic problems were measured using the Expanded Disability Status Scale (Kurtzke, 1983), a standard observer-reported measure of neurologic function which emphasizes ambulation disability. Psychological morbidity was evaluated in both studies using the AIMS depression and anxiety subscales. High scores indicate increased functional problems in the above measures. 2.2.2. Coping behavior Coping repertoire was measured in both studies using the WCQ (Folkman and Lazarus, 1988), a standard coping measure which asks individuals to endorse how often they used each coping strategy to cope with a speci®c stressful encounter that the subjects chose each time they completed the booklet. Coping ¯exibility was measured using the Flex, a card sort measure which asks individuals to describe hypothetical or actual reported behavior by asking participants how likely they are to use a particular strategy in coping with a speci®c situation which they select (Schwartz and Daltroy, 1991; see Schwartz, 1990 for empirical and systematic evaluation of the impact and ecological validity of the situations; see Schwartz et al., 1998 for items and sort situations included in the Flex). This test requires subjects to place 20 coping response cards on a sorting sheet to describe how they would cope or have coped with a speci®c stressful situation chosen from six life domains: work, family, recreation, activities of daily living, self-image/con®dence and pain/fatigue. The 20 coping strategies exemplify acceptance, problem-solving, social support and negative approaches. Coping ¯exibility is de®ned by the change of card placement in their coping pro®les between sorts. Sense of control was operationalized in both studies to include self-ecacy and locus of control. In study 1, self-ecacy was measured using the Arthritis SelfEcacy scale (ASES) (Lorig et al., 1989) and sense of control was measured using the short form of the Arthritis Helplessness Index (AHI) (Nicassio et al., 1985) and Rotter's Locus of Control Scale (LOC) (Rotter, 1966). The Multidimensional Health Locus of

Control Scale (Form C) (MHLC) was used in both studies (Wallston et al., 1978). In study 2, self-ecacy was measured using the MS Self-Ecacy Scale (Schwartz et al., 1996a). High scores indicate increased helplessness on the AHI, increased internality on the LOC and the MHLC and a stronger sense of self-ecacy on the ASES and MSSE. 2.2.3. Measurement artifacts As the packets were completed by mail, participants were asked to provide information about possible measurement artifacts which could in¯uence their scores. These items tracked: (1) how much each sort situation applied to the patient's own experience; (2) the period of time between testing dates; (3) whether the patient reported receiving assistance to complete the Flex (yes/no) and (4) how many sittings the patient required to complete the questionnaire packet. 2.2.4. Constructs measured only in study two Neuropsychological performance was assessed in study 2 using the Rao brief screening cognitive battery (Rao et al., 1991), the Wisconsin Card Sorting Task (Berg, 1948) and the Trail Making Test (Reitan, 1958; see Schwartz et al., 1996b for complete description of the neuropsychological battery). All neuropsychological tests scores included in this study were adjusted for age, educational level and gender using published normative standards. A neuropsychological composite was created, which was the mean of each patient's T-scores for the neuropsychological tests. Eudaimonistic well-being was measured in study 2 using the Ry€ Happiness Scale, which has subscales for environmental mastery, purpose-in-life, personal growth, self-acceptance and social relatedness (Ry€, 1989). The eudaimonistic model extends the idea of health to comprise existential aspects such as self-realization, ful®llment and the development of one's intrinsic potential (Maslow, 1962; Smith, 1981). 2.3. Procedure Both studies included mailed surveys and study 2 also included an intake interview. The mailed surveys were implemented using Dillman's Total Design Method (Dillman, 1978) to ensure that a large proportion of study participants would complete the study (72 and 79% agreed to participate and 81 and 96% successfully completed studies 1 and 2, respectively). Informed consent was obtained by mail (study 1) or in-person (study 2). Retest data were collected in both studies approximately two weeks later. The average period of retest was 20 days (S.D. = 10, range = 6 to 63 days) for study 1 and 14 days for study 2 (S.D. = 8, range = 2 to 56 days). For the analyses presented herein, only

C.E. Schwartz, L.H. Daltroy / Social Science & Medicine 48 (1999) 619±631

people who completed the Flex retest within 45 days were retained (n = 118 and 101, for study 1 and study 2, respectively). Participants completing the questionnaire packet were asked to sort the cards using the same sort situations (e.g. work, family, etc.) and speci®c examples as they had chosen in the baseline questionnaire. Whereas the ®rst study relied on data collection by mail for both test and retest, the second study taught participants how to do the Flex in the context of an intake interview and then asked them to complete the Flex at home on their own. Although this approach may have added some method variance, the expected reduction in error variance was deemed to be worth this trade-o€. In the second study, the number of sorts on the Flex was reduced from six to three and one coping response card (No. 11) was changed from ``I let myself feel disappointed'' to ``I let myself feel frustrated'' in response to suggestions made by MS patients when the Flex was pre-tested for use in study 2. These changes should not a€ect results because the Flex format and the content of the coping response cards remained consistent throughout the study. 2.4. Statistical analysis Correlational analyses were done to test speci®c hypotheses about whether inconsistency in reported coping behavior (i.e. low test±retest reliability on the Flex) was due to measurement artifact or to a meaningful behavior pattern. Test±retest reliability was also computed on the WCQ in study 1, but WCQ retest data were not collected in study 2. For the WCQ, the Kendall rank correlation (i.e. tau) coecient was computed within subjects between items from the two testing occasions (Kendall, 1962). For the Flex, Spearman rank correlation coecients were computed within subjects between each of the two repeated sorts (Spearman, 1904). An individual's inconsistency score on the Flex was the mean of the Spearman correlation coecients across the two repeated sorts. Thus, a consistent person would have a high, positive reliability score (e.g. 0.80), re¯ecting their having ranked the coping response cards similarly for the same two coping 1 Raw scores of the correlation coecient do not allow one to distinguish the magnitude and the direction of association with other variables of interest. As an example of how the raw score might lead to some confusion, consider a negative correlation between the inconsistency score and depression. This ®nding could indicate that either lower (positive sign) inconsistency is associated with more depression or that high (negative sign) inconsistency is associated with more depression. Rescaling the scores to range from zero to one removes this ambiguity.

623

situations across time points. An inconsistent person would have a low, positive score or a negative score (e.g. +0.20, ÿ0.20), indicating that their coping response cards were ranked substantially di€erently across time points. For example, a consistent person might rank the card ``I call a friend'' in the ``a little like me'' (+1) and ``a little more like me'' (+2) columns across the two repeated Recreation sorts; an inconsistent person might rank the card in the ``a little more like me'' (+2) and the ``a little unlike me'' (ÿ1) columns across the same two sorts. In the ®rst case, the aggregate reliability coecient would be highly positive; in the second, the coecient would be low and/or negative. To simplify interpretation, Flex reliability scores were rescaled to range from zero to one, with low scores indicating inconsistency1. To increase statistical power and to minimize the use of arbitrary cut-o€s, the consistency coecient was retained as a continuous variable. After all of the individual hypotheses were tested, we used hierarchical general linear modeling (Box et al., 1978) to examine how much independent variance in inconsistency could be attributed to each salient set of factors. A separate model was run for each set of predictors to derive an estimate of the variance accounted by each factor (e.g. measurement artifact, neuropsychological, personality). In cases where several highly correlated predictors were to be examined simultaneously, we sought to avoid problems of multicollinearity by computing two composites from the eudaimonistic well-being and psychological morbidity using principal components analysis with varimax rotation. We included in the composites those well-being and psychological morbidity predictors which had at least a trend association with inconsistency. We then included all of the predictors together in one model to estimate the total variance accounted for in inconsistency. 2.5. Hypothesis testing Two sets of hypotheses were tested in both studies. The ®rst set investigated whether inconsistency in reported coping behavior was a measurement artifact. The second set investigated whether this inconsistency was systematically associated with behavioral and psychological problems, thereby re¯ecting a meaningful behavior pattern. Table 2 outlines the measurement artifact hypotheses evaluated in both studies. 2.5.1. Measurement artifact hypotheses First, we reasoned that if inconsistency were speci®c to the Flex, rather than to the measurement of coping in general, we would expect the test±retest coecients to be statistically di€erent on the Flex than on another coping measure. To test this hypothesis, we compared

ÿ0.16***

0.06

ÿ0.22*

ÿ0.06

Test±retest interval (continuous)

Grouping people who needed assistance (binary)

Multiple sittings (binary)

ÿ0.03

Not supported. Flex unreliability was not associated with number of sittings required by patient to complete questionnaire packet.

Supported. Flex unreliability was associated with requiring assistance to complete the task. Impact: subsequent analyses will adjust for variance due to requiring assistance.

Not supported. Flex unreliability was not associated with the delay between test and retest.

Not supported. Flex unreliability was not associated with the relevance of the sort situation to the patient's experience.

Not supported. Reliability coecients of both coping measures were signi®cantly associated and had similar medians (0.59 and 0.60 for Flex and WCL retest reliability, respectively).

Conclusion

p < 0.10. *p < 0.05.**p < 0.01.***p < 0.001. aIt should be noted that low scores on the inconsistency coecient represent low levels of consistency.

+

ÿ0.07

ÿ0.07

Applicability of sort (interval)

±

±

0.53***, NA

WCQ reliability (Kendall t)

Flex unreliability is simply random error. Flex unreliability will not be correlated with WCQ unreliability (i.e. accept H0: r = 0) The median of Flex unreliability will be di€erent from the medianof the WCQ unreliability (i.e. reject H0: Wilcoxon z = 0) Flex unreliability is due to low ecological validity. Flex unreliability will be associated with low applicability of sort situations to patient's experience (i.e. reject H0: r = 0) Flex unreliability is due to life changes which occurred in the period of time between test and retest. Flex unreliability will be correlated with test±retest interval (i.e. reject H0: r = 0) Flex unreliability is due to systematic error generated by surrogate assistance to the patient when completing questionnaires. Flex unreliability will be correlated with needing assistance (i.e. reject H0: r = 0) Flex unreliability is due to unidenti®ed changes (e.g. in mood or other state) resulting from completing the questionnaires in more than one sitting. Flex unreliability will be correlated with requiring multiple settings to complete questionnaire (i.e. reject H0: r = 0)

study 2

Correlation with Flex reliability study 1

Variable

Hypothesis

Table 2 Associations of Flex inconsistency with measurement artifact hypothesesa

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C.E. Schwartz, L.H. Daltroy / Social Science & Medicine 48 (1999) 619±631

the correlation between test±retest reliability on the Flex to that of the WCQ, a standard coping measure. We also compared the distributions of the consistency coecients for the two coping measures using the Mann±Whitney Wilcoxon test, a nonparametric test for evaluating the two-tailed null hypothesis that there is no di€erence between the dispersion or variability of two sets of scores (Wilcoxon, 1945; Mann and Whitney, 1947). We would expect that the test±retest reliability scores for the two tests would be correlated (i.e. a signi®cant p-value) and that the two distributions would be similar (i.e. a nonsigni®cant p-value). Second, we tested whether inconsistency on the Flex was due to the sort situations being irrelevant to the patient's experience. If the situations were not ecologically valid, we would expect that they were reporting hypothetical or ideal behavior, rather than actual behavior. We tested this hypothesis by computing the correlation between inconsistency on the Flex and the patient's answer to a Likert-scaled question which asked how much each sort situation applied to their own experience. Third, we tested whether inconsistency on the Flex was due to changes which may have occurred in the period of time between test and retest. Although this is an indirect proxy, one would expect the period of time between tests to be correlated with the probability of change. If the delay between the ®rst and second tests were associated with unreliability, then we would conclude that inconsistency re¯ects changing conditions, rather than de®cits in reporting. To test this hypothesis, we computed the correlation between Flex inconsistency and the delay between test and retest. Fourth, we sought to evaluate whether people who required assistance in completing the Flex had systematically lower consistency scores. If this were the case, then some of the inconsistency would be due to surrogate reporting or to method variance. To test this hypothesis, we computed the correlation between Flex unreliability and surrogate assistance. Finally, we sought to evaluate whether unidenti®ed changes (e.g. in mood or other state) which resulted from completing the questionnaires in more than one sitting might have a€ected the inconsistency scores. To test this hypothesis, we computed the correlation between inconsistency on the Flex and whether the patient completed the questionnaire packet in more than one sitting. All of these predictors were also tested in a multivariate linear model to evaluate whether their predictive signi®cance changed when examined in combination. The last three measurement artifact hypotheses were re-evaluated in study 2 using data from the MS patients.

625

2.5.2. Meaningful behavior pattern hypotheses If the above artifactual explanations fail to account for a signi®cant amount of the variance in inconsistency scores, then inconsistency might represent a meaningful aspect of the coping process, with implications for coping theory and intervention. We tested ®ve hypotheses that inconsistency re¯ects a genuine behavior pattern. First, we hypothesized that inconsistency would be associated with functional problems since chronic loss would make it more dicult to maintain a stable sense of self. We computed correlations of inconsistency on the Flex with physical and psychological problems, as well as with the reported global impact of the illness. Second, we hypothesized that inconsistency re¯ects having a larger coping repertoire and using strategies within the repertoire interchangeably (i.e. randomly), even in response to the same stressful situation. To test this association, we computed a Spearman correlation (Spearman, 1904) between inconsistency and the number of items on the WCQ which were endorsed `sometimes' or `regularly'. Third, we hypothesized that inconsistency re¯ects an underlying process of haphazard grasping for solutions. This process would be related to feeling impotent to a€ect positive change and would result in higher reported helplessness scores, lower reported selfecacy, and external general or health-related locus of control. The last two hypotheses, tested only in study 2, were that inconsistency in reported coping re¯ected de®cits in cognitive functioning or reduced well-being and self-knowledge. 3. Results 3.1. Descriptive statistics In study 1, both the WCQ and the raw Flex test± retest scores ranged from negative to positive values and were slightly negatively skewed. The WCQ tau statistics ranged from ÿ0.05 to 0.92, with a median of 0.59. In study 1, the raw Flex correlation coecients ranged from ÿ0.19 to 0.89, with a median of 0.59. After rescaling, the median Flex retest coecient was 0.72 and its mean was 0.69. In study 2, the rescaled Flex reliability scores ranged from 0.12 to 0.92, with a median of 0.58. 3.2. Hypothesis testing for measurement artifacts Results of study 1 revealed that the WCQ and Flex inconsistency scores were moderately associated and their distributions were not di€erent (Table 2). These ®ndings suggest that inconsistency on the Flex is not simply due to random error, but is a consistent attribute of measured coping behavior. We also found that

626

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inconsistency on the Flex was not associated with the presumed index of low ecological validity, with the test±retest interval, or with completing the questionnaire in more than one sitting. The only measurement artifact which was associated ( p < 0.05) with inconsistency was surrogate assistance. Consequently, subsequent analyses used partial correlations which adjusted for whether the patient required assistance to complete the questionnaires. It should be noted that subsequent analyses which adjusted for requiring surrogate assistance did not substantially alter the magnitude of associations (data shown only for adjusted correlations). Results of study 1 were replicated in study 2. Inconsistency in reported coping behavior was not associated with the period of time between test and retest or completing the questionnaires over multiple sittings, but it was associated with requiring surrogate assistance to complete the questionnaires. Subsequent analyses consequently adjusted for requiring surrogate assistance. 3.3. Hypothesis testing for behavior pattern Results of study 1 revealed that inconsistency in reported coping behavior was associated with functional problems: it was most strongly associated with psychological morbidity, such as higher levels of reported depression and anxiety (Table 3) and somewhat less strongly associated with physical limitations and the global impact of illness. We found that inconsistency in reported coping behavior was unrelated to the size of one's coping repertoire, but that it was associated with an external locus of control, more reported disease-speci®c helplessness and a lower sense of self-ecacy. It was not associated with health-related internal locus of control. In study 2, we found that physical functional problems and overall role limitations were not associated with inconsistency in reported coping behavior, but depression was moderately associated and there was a trend association with anxiety (i.e. p < 0.10) (Table 3). There was also a trend such that people who were more external in their health-related locus of control exhibited greater inconsistency in reporting their coping behavior. This ®nding was similar to the reported associations from the ®rst study on generalized locus of control and disease-related sense of helplessness, and in contrast to the lack of association with healthrelated locus of control in the ®rst study. The relationship between self-ecacy and inconsistency was not replicated, but study 2 did replicate the ®nding that coping repertoire was not associated with inconsistency in reported coping behavior. We found that inconsistency in reported coping behavior was associated with both overall and speci®c

de®cits in neuropsychological performance. In particular, we found that inconsistency in reported coping behavior was associated with worse performance on tests of long-term verbal storage and retrieval, and two measures of complex attention (TrailMaking B and the Symbol-Digit task). Inconsistency was not associated with performance on the Wisconsin Card Sort measure of frontal lobe function, on the spatial memory task, on the PASAT measure of complex attention or on the Controlled Oral Word Association task. Finally, we found that people who were more inconsistent in reporting their coping behavior tended to report reduced well-being, as re¯ected by a lower sense of mastery, purpose in life, personal growth and selfacceptance. There was a trend association between inconsistency and reporting lower levels of social relatedness. 3.3.1. Testing competing hypotheses: accounting for variability in unreliability Hierarchical modeling was done to explore the independent and simultaneous contribution of each of the categories of predictors in explaining inconsistency in reported coping behavior. Only signi®cant univariate factors were included in the hierarchical modeling. Consequently surrogate assistance was the only measurement artifact included in the multivariate models. The principal components analysis yielded two orthogonal composites which contained the well-being subscales and the psychological morbidity subscales. The ®rst composite had higher factor loadings on the former and the second had higher loadings on the latter. By including these orthogonal composites in the ®nal hierarchical analysis, we were thus able to examine the independent contribution of each category of predictor. Hierarchical modeling revealed that measurement artifact accounted for less than one percent of the variance in inconsistency in reported coping behavior and that an additional 21% of the variance could be explained by the behavioral factors, including neuropsychological problems (9%), psychological morbidity (4%), locus of control (3%) and eudaimonistic wellbeing (5%) (Table 4). Thus, more variance in inconsistency in reported coping behavior was explained by behavioral and psychosocial factors than by the tested measurement artifacts. We therefore conclude that inconsistency in reported coping behavior does indeed re¯ect a meaningful behavior pattern, rather than simply random error. 4. Discussion As both Heraclitus and Ahphonse Karr noted long ago, change is a constant in life; yet there is an under-

Not evaluated

Neuropsychological performance

Well-being

Composite (mean T-score) Individual tests: Verbal Long-term Storage; Verbal Long-term Retrieval; Wisconsin Card Sort; Controlled Oral Word Association: PASAT; 10/36 spatial; TrailMaking A; TrailMaking B; Symbol Digit Mastery; Purpose in life; Personal growth; Social relatedness; Self-acceptance

NA

NA ÿ0.18+ NA ÿ0.004 0.11

ÿ0.33*** ÿ0.05 ÿ0.29** 0.19* 0.21* 0.20* NA

0.10 0.07 0.16 0.38** 0.28* 0.24* 0.25* 0.25* 0.19+ 0.27**

0.29** 0.30* 0.28* 0.11 0.10

0.02 ÿ0.07 ÿ0.33*** ÿ0.19+ ÿ0.13 ÿ0.02

Study 2

ÿ0.26** ÿ0.19* ÿ0.27** ÿ0.25** ÿ0.22* ÿ0.13

Study 1

Partial correlation after adjusting for whether patient required surrogate assistance. It should be noted that low scores on the inconsistency coecient represent low levels of consistency. NA = not available. +p < 0.10. *p < 0.05. **p < 0.01. ***p < 0.001.

a

Self-ecacy

MS Self-ecacy Control

Internal health-related LOC; MS Self-ecacy Function

Impact of illness Coping behavior Sense of control Locus of control (LOC)

Psychological morbidity

Generalized LOC; Internal Health-related LOC; Arthritis Helplessness Index; Arthritis Self-ecacy Function Arthritis Self-ecacy Pain; Arthritis Self-ecacy Symptoms Not evaluated

Measure used in study 2 SIP physical; Extended Disability Status Scale AIMS depression; AIMS anxiety SIP overall Coping repertoire

Measure used in study 1 AIMS mobility; AIMS activities of daily living AIMS depression; AIMS anxiety AIMS impact of illness coping repertoire

Functional problems Physical problems

Construct

Table 3 Associations of Flex inconsistency with behavior patternsa

C.E. Schwartz, L.H. Daltroy / Social Science & Medicine 48 (1999) 619±631 627

628

C.E. Schwartz, L.H. Daltroy / Social Science & Medicine 48 (1999) 619±631

Table 4 Hierarchical regression models predicting inconsistency in reported coping behavior Predictor

Standardized parameter estimate Dependent Variable: inconsistency in reported coping behaviora model 1

Surrogate assistance Neuropsychological performance Depression and anxiety composite Locus of control Eudaimonistic well-being composite Model R 2

ÿ0.09

0.01

model 2 0.29**

0.09**

model 3

ÿ0.19+ 0.04+

model 4

ÿ0.18+ 0.03+

model 5

model 6

0.23* 0.05*

ÿ0.04 0.28** ÿ0.19* ÿ0.21* 0.20* 0.21***

It should be noted that low scores on the inconsistency coecient represent low levels of consistency. *p < 0.05. *** p < 0.001.

lying and undeniable structure to personality (Funder and Colvin, 1991). Our ®ndings suggest that rather than re¯ecting measurement error, inconsistency in reported coping behavior re¯ects a behavioral pattern that is associated with cognitive diculties, existential problems, depression and a low sense of control. Hence there is an underlying structure and meaning to the inconsistency. Inconsistency in reported coping behavior may indicate a tendency for haphazard coping behavior, which could mediate the relationship between coping e€orts and health outcomes. For example, inconsistent reporters may have cognitive and psychosocial de®cits which make it dicult for them to recognize when a coping e€ort is appropriate or successful. Consequently, e€ective or context-appropriate coping e€orts on behalf of inconsistent reporters may not result in their generalizing these e€orts to other similar situations. Similarly, inconsistent reporters may be unlikely to learn from ine€ective e€orts if they are unable to recognize when a coping e€ort is unsuccessful. This inability to learn from one's success and failure may exacerbate a sense of helplessness and depression, leading to an escalation of maladaptive behavior. The context of chronic illness can necessitate a changing sense of self. As formerly appropriate ways of describing the self become obsolete, individuals may face an existential angst and may feel challenged to maintain a sense of his/her essence (Schwartz, 1995). Individuals facing a signi®cant health challenge may scale down their expectations of health, may be more appreciative of the social resources which support their activities of daily living, and may be making signi®cant shifts in the importance of life domains (Bach and Tilton, 1994) to maintain an acceptable level of perceived quality of life. Inconsistent copers may lack a stable and meaningful self-evaluation process which may impede their ability to engage in an adaptive `re-

**

p < 0.01.

sponse shift'. This emerging construct in quality-in-life research refers to a change in the internal standards, values and the conceptualization of quality of life for individuals facing a signi®cant health challenge (Breetvelt and VanDam, 1991; Sprangers and VanDam, 1994; Sprangers, 1996; Sprangers et al., under review; Sprangers and Schwartz, in press). If one lacks the cognitive skills to make meaningful shifts in their internal standards or in their priorities, one may also be vulnerable to cognitive distortions and maladaptive interpretations of somatic symptoms (Smith et al., 1988; Dworkin, 1991), both of which may induce depression and exacerbate functional disability (Von Kor€ et al., 1992; Sullivan et al., 1992). Future research might directly address the relationship of coping inconsistency and response shift. Although our ®ndings are intriguing, there are some important limitations which merit mention. First, we did not evaluate the relationship between inconsistency in reported coping behavior and unreliability in trait measures. Although the WCQ and the Flex had similar inconsistency score distributions, the validity of our conclusions would be threatened if the inconsistent copers also exhibited unreliability in trait measures. Further, we do not know the WCQ referent problems selected for test and retest. If the two referent problems varied in controllability, then that di€erence may contribute to inconsistency. Similarly, as reported repertoire size may be a€ected by the referent problem, the lack of association between coping repertoire and inconsistency may be due to the referent problem selected by the individual. Finally, the magnitude of the correlations re¯ect a small to medium e€ect size using the Cohen (1992) criteria, so the behavioral pattern revealed may be a subtle one. Future research might evaluate the association between test±retest reliability in trait measures and coping measures, and use the same patient-speci®ed referent problem for the WCQ test±retest reliability estimate.

C.E. Schwartz, L.H. Daltroy / Social Science & Medicine 48 (1999) 619±631

A second limitation is that both studies measured reported rather than observed coping, so we cannot know whether this inconsistency is due to problems in reporting, problems in coping or both. The cross-sectional nature of the data limit our ability to tease apart cause and e€ect. That is, the reason for the poor adjustment may lie in the fact that the sample consisted of chronically ill people who may be in some sort of crisis and that inconsistent coping may be a result rather than a determinant of poor quality of life. Further, we are unable to evaluate whether inconsistency is related to speci®c changes in coping behavior patterns over time and whether these changes imply ine€ective feedback within the individual between action and outcome. As Folkman and Lazarus (1985) point out, stressors have di€erent stages and what may be e€ective at one stage may not work within the same stressful event at a di€erent stage. Future research should examine the impact of inconsistent coping over time and should address whether the observed inconsistency in reported coping behavior is random, whether it forms some sort of pattern, and what those patterns might be related to in terms of personality, life cycle stage of the stressor, or psychosocial and functional well-being. There were some di€erences in ®ndings between the two studies, speci®cally with regard to the role of sense of control. The ®rst study found no impact of healthrelated locus of control but did ®nd an association between inconsistency and other measures of control and disease-speci®c self-ecacy. In contrast, the second study found an association between health-related locus of control but not with disease-speci®c self-ecacy. This contrast may be due to using di€erent measures of self-ecacy in the two studies or to de®ciencies in the criterion validity of the MHLC (Wallston, 1992). Since the operationalization of selfecacy requires situation- or disease-speci®c contexts (Bandura, 1977), it is not possible to evaluate the convergent validity of the two measures. Di€erences in disease duration or illness experience between the two samples may also explain di€erences in health-related locus of control. Indeed, past research suggests that less disabled people tend to report an internal locus of control (Wassem, 1991) and that people with an internal locus of control tend to become more polarized over the course of a personality test (Knowles, 1988). Thus di€erences in the association between sense of control and inconsistency may be moderated by disease duration. Future work might replicate the ®rst or second study on an independent sample of similar patients and might use a multi-dimensional measure of sense of control with documented criterion validity (cf. Shapiro Control Inventory; Shapiro, 1994). In conclusion, inconsistency in reported coping behavior seems to be meaningful and seems to re¯ect a

629

constellation of psychosocial problems which are measurable, replicable and theoretically linked. Distinguishing between the maladaptive and adaptive aspects of variability would be an important step towards understanding response shift phenomenon. Further, given the relevance of response shift for coping, the analytic approach described herein might lead to new avenues for revealing response shift. Future work might use qualitative methods to explore the existential and developmental processes implicated in the present work.

Acknowledgements We would like to thank Oded Ben-Arush, Katy Benjamin, Carla Chandler, Ph.D., Terry Fenton, Ph.D., Fred Foley, Ph.D., Naomi Lester, Ph.D., Rose Moss, David Waldman, Ph.D. and Mirjam Sprangers, Ph.D., for their helpful comments. We would like to thank Elissa Laitin for assistance with data analysis and Rebecca Feinberg for assistance with manuscript preparation. This work was funded by grants to C.E.S. from the Arthritis Foundation and the Lupus Foundation (Dissertation Fellowships); the National Multiple Sclerosis Society (FG 880-A1; RG 2577-A-2); the Fetzer Institute (Project #563) and the Agency for Health Care Policy and Research (RO1 HS08582) and by a grant to L.H.D. from the National Institutes of Health (#AR36308).

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