Can a patient educational book change behavior and reduce pain in chronic low back pain patients?

The Spine Journal 4 (2004) 425–435

Can a patient educational book change behavior and reduce pain in chronic low back pain patients? Brian E. Udermann, PhD, ATCa,*, Kevin F. Spratt, PhDb, Ronald G. Donelson, MD, MSc, John Mayer, PhD, DCd, James E. Graves, PhDe, John Tillotson, PhDf a

Department of Exercise and Sport Science, University of Wisconsin, La Crosse, 37 Mitchell Hall, La Crosse, WI 54601, USA Iowa Testing Programs, University of Iowa Back Care, Iowa Spine Research Center, University of Iowa, Iowa City, IA 52242, USA c Department of Surgery, Orthopedic Section, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756, USA d U.S. Spine and Sport Foundation, 4130 La Jolla Village Dr., #300, La Jolla, CA 92037, USA e Department of Exercise Science, Syracuse University, Bldg. 820, Comstock Avenue, Syracuse, NY 13244, USA f Department of Science Teaching, Syracuse University, 101 Heroy, Syracuse, NY 13244, USA b

Received 10 January 2003; accepted 6 January 2004

Abstract

BACKGROUND CONTEXT: This study was prompted by 1) the almost universal use of patient education as an initial or at least an ancillary step in the treatment of patients presenting with low back pain, 2) the relative dearth of studies evaluating the effectiveness of patient education and 3) the complete lack of support in the few existing studies for the efficacy of education in improving patients’ long-term health status. PURPOSE: A feasibility study to evaluate the efficacy of an individualized biomechanical treatment educational booklet to effect improvement in health status. STUDY DESIGN: A prospective, longitudinal cohort study. PATIENT SAMPLE: Sixty-two subjects (35 female, 27 male), average age 42.4 years, reported a mean duration of back pain before inclusion of 10.4 years. However, because of attrition, only 48 subjects had complete data across the 18-month follow-up period. OUTCOME MEASURES: Outcome measures included pain status, number of back pain episodes, subject compliance with self-care behaviors, knowledge and opinion of booklet content. METHODS: Volunteers with chronic low back pain were provided a copy of an individualized biomechanical treatment educational book and told they would undergo a written survey of its content 1 week after reading the book. Subjects’ health status at 9 and 18 months was evaluated using a structured telephone interview. RESULTS: One week after the 62 subjects, with an average of 10.4 years of symptoms and extensive use of the medical system, finished reading the index book, 51.62% reported noticeable improvement in their pain, their content comprehension was good and opinions about the text were generally positive. At 9-month follow-up, there was statistically significant and clinically relevant improvement in reported pain magnitude (p⬍.03), number of episodes (p⬍.0001) and perceived benefit (p⬍.04). At 18-month follow-up, these gains held or demonstrated even further improvement. CONCLUSION: This study’s results suggest that the Treat Your Own Back book may have considerable efficacy in helping readers decrease their own low back pain and reduce the frequency of, or even eliminate, their recurrent episodes. These findings also justify conducting a randomized controlled clinical trial to assess this book’s efficacy in improving health status in subjects with low back pain with the study design including internal controls to minimize bias issues and a wider

FDA device/drug status: not applicable. Nothing of value received from a commercial entity related to this research. 1529-9430/04/$ – see front matter doi:10.1016/j.spinee.2004.01.016

쑖 2004 Elsevier Inc. All rights reserved.

* Corresponding author. University of Wisconsin, La Crosse, 1725 State Street, La Crosse, WI 54601, USA. Tel.: (608) 785-8181. E-mail address: [email protected] (B.E. Udermann)

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range of outcomes, including measures of pain, function, disability, patient satisfaction, utilization of health care services and psychosocial measures. 쑖 2004 Elsevier Inc. All rights reserved. Keywords:

Low back pain; Educational book; Posture; Exercise; Self-care; Efficacy

Introduction Patient education has been a prominent part of the care of low back pain (LBP) for the past two decades based on the belief that recovery from LBP can be enhanced if those who experience it better understand the nature of their problem(s) [1]. Recent clinical guidelines panels have based their educational recommendations on evidence that inactivity and belief that LBP is a serious problem greatly interfere with recovery [2–4]. A common medium for patient education is a small book or pamphlet, most often used as a supplement to active patient management. Despite their widespread use, the educational content of these books and their effectiveness have not been extensively studied. Three book types are in common use, labeled here as 1) traditional biomechanical, 2) evidencebased and 3) individualized biomechanical. Historically, the majority of educational booklets have taken a “traditional biomedical” approach, including a basic overview of spinal anatomy, explanations of various (established and unestablished) mechanisms and anatomic sources of pain, many recommending the avoidance of pain, even bed rest, and/or use of exercise for aerobic benefit or to strengthen trunk musculature after pain has subsided. Newer books, evolved directly from LBP clinical guidelines recommendations, take an “evidence-based” approach [5,6], focusing on patients’ beliefs and attitudes by teaching the advantages of remaining active and avoiding bed rest, combined with reassurance that there is likely nothing seriously wrong. There are typically limited recommendations regarding which specific activities or exercises to engage in or avoid in each of these book types. The individualized biomechanical book type guides readers through a self-assessment process, starting with initial screening questions. Treat Your Own Back (TYOB), first published in 1980 by McKenzie [7], is such a book. It teaches readers certain patterns of pain response that often occur as the result of performing specific test positions and/ or repetitions of spinal bending motions, involving end-range flexion and extension especially. Readers’ patterns of pain response to these tests provide them with immediate feedback concerning the benefit or detriment of each activity and position in each direction of testing. A single direction of testing is commonly found that diminishes or abolishes their pain, often with lasting improvement [8,9]. Strategic use of that direction then becomes the foundation of the readers’ self-treatment program, and other directions that provoke or worsen pain are temporarily avoided to assist in preventing the return of the pain.

Despite the pervasive availability and use of educational booklets and materials directed to patients presenting with low back troubles, only five studies could be identified that assessed the impact of educational books on outcomes [5,10– 13]. The results of these studies were mixed. One evidencebased booklet showed no benefit at 7 weeks for five measured outcomes: 1) satisfaction with care, 2) perceived knowledge, 3) participation in exercise, 4) functional status, 5) symptom relief and 6) health-care use [5]. That same book was then used as a control in a randomized controlled trial and found to be of similar effectiveness as both chiropractic manipulation and physical therapy [12]. A third study of an evidencebased booklet that focused on patients’ beliefs and attitudes about LBP reported significant decreases of patients’ fears, but the reported decrease in pain and disability was not statistically significant [10]. A fourth study of a traditional biomechanical booklet demonstrated decreased specialist referrals over the next year, but no other significant effects were reported [11]. A fifth study compared outcomes for a nonindividualized self-management book issued in physician offices with both physician advice concerning activity and bed rest, and a group receiving both the book and the advice [13]. The study reported a decrease in patients’ pain with the book at 1 week, but not at 3 weeks. An interesting negative interaction was reported for those receiving both this book and also specific physician advice to exercise as soon as pain allowed and continue in the long term. At 1 week, there was much less benefit than with either intervention alone. Thus, no educational book has demonstrated any long-term effects on pain or disability. No formal evaluation of TYOB, an assessment-based biomechanical educational booklet, has been conducted. In light of the limited literature concerning the evaluation of educational booklets for patients presenting with low back troubles, the lack of standards for what outcomes are valid for such assessments, the weak evidence for efficacy thus far reported and a lack of evidence that educational booklets are effective in reducing symptoms and disability, it was decided that an initial prospective longitudinal cohort study was an appropriate design to establish the feasibility of more carefully evaluating the efficacy of educational booklets. Such a design is advantageous because of low cost, relative ease of conscripting subjects (no randomization and, therefore, no refusal to accept the treatment modality in the study) and the requirement of following patients across time to evaluate changes in outcomes. By assessing patients’ compliance with instructions, such things as changes in behavior, changes in symptoms across time, preliminary evidence of booklet efficacy and perhaps mechanisms associated with efficacy might be established.

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This study’s twofold purpose was to identify any evidence of impact on selected health outcomes from reading TYOB and to determine whether such impact was sufficient to motivate a randomized controlled trial to more fully investigate the efficacy of this educational approach to the care of low back pain.

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Nine-month telephone survey This survey again focused on subjects’ compliance, pain status and self-care behaviors. Specifically addressed was their use of postural strategies and exercises emphasized in the book, changes in current pain severity, number of episodes since reading the book and to what extent improvements may have been related to self-care behavior changes resulting from reading the book.

Methods Recruitment

Eighteen-month telephone survey

Study participants were volunteers recruited by means of advertisements, that is, newspaper advertisements and online notices available to faculty, staff and students in a university community, asking persons with a history of LBP to volunteer to participate in a study. Potential volunteers who had previously either read TYOB or undergone McKenzie therapy for low back pain were excluded.

As with the 9-month survey, the focus was on continued compliance, patient health status relative to pain and symptoms and continued use of the book to guide their address of their symptoms. For the qualitative items in the initial survey, comments were classified into five categories and, within each category, each comment was coded as either positive or negative. The five categories were style, general comment, posture comment, exercise comment and action comment. Examples of positive and negative comments for each category are summarized in Table 1.

Procedure After signing an informed consent approved by Syracuse University’s Institutional Review Board, subjects were given a copy of the Treat Your Own Back book and informed they would be asked questions covering the book’s content 1 week after they finished reading the book. Each subject completed a written survey at 1 week and were informed they would be contacted for follow-up interviews. Attempts were made to contact all subjects for a telephone survey at 9 months and then again at 18 months. For those difficult to locate, a minimum of 10 phone attempts were made over varying times of the day with the additional use of directory assistance.

Materials Materials consisted of the Treat Your Own Back book, described above; a paper and pencil patient self-report survey completed by the patient 1 week after being admitted into the study; and structured telephone interview surveys for 9and 18-month follow-ups.

Data analysis Each wave of data was entered into a structured Excel spreadsheet. Double data entry with a minimum of a 1-week interval between entry sessions was done by one of the investigators. Data were imported into the SAS System version 8.2 running under Windows NT or Windows Professional 2000. Because the three assessments of treatment efficacy (1 week, 9 months and 18 months) constitute repeated measurement, all three outcomes (pain magnitude, number of LBP episodes and perceived benefit) were assessed simultaneously within a one-way multivariate analysis of variance general linear model (MANOVA) using the Wilks’ lambda test statistic, where Type I error rate was set at .10. Given a significant Wilks’ lambda, follow-up univariate ANOVAs were planned to evaluate the three-level assessment time

Table 1 Summary of 1-week survey categories for classifying patient’s write-in comments regarding the Treat Your Own Back text Category

Type

Example

One-week survey

Style comment

The 1-week survey assessed subjects’ personal and health demographics; knowledge of the TYOB book based on a 25-item true/false test; opinions about the booklet regarding clarity of language, effectiveness of pictures and adequacy of directions in doing exercises; general health-related opinions and changes in their self-care initiated as a result of reading the book.

Content comment

Positive Negative Positive Negative Positive Negative Positive Negative Positive Negative

The writing was clear I couldn’t understand the text Information is important to know Nothing new here Became aware of posture issues Role of posture overemphasized Exercise is important Exercises suggested aren’t appropriate I will seek work accommodations I can’t make the suggested changes

Posture comment Exercise comment Action comment

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main effect for each outcome separately, again with Type I error rate set at .05. Finally, significant univariate assessment time main effects were interpreted by testing for pairwise differences between the three means (ie, 1-week vs. 9-month, 1-week vs. 18-month and 9-month vs. 18-month outcomes) using Tukey’s highest significant difference (HSD) procedure, again with Type I error rate set at .05. The use of parametric analyses with outcomes that are ordinal and, in the case of the perceived benefit outcome, binary remains controversial in spite of the work presented by Hse and Feldt [14], who demonstrated that results were quite consistent between parametric and nonparametric data analysis approaches with ordinal data, even binary data when, as was the case with these data, the binary split is not extreme. The advantages of the parametric approaches are often greater power and flexibility in specifying models. Nevertheless, both the pain magnitude and perceived benefit outcomes were also analyzed using repeated measures categorical data modeling procedures to determine if differential interpretations might be observed. There are currently no nonparametric approaches that allow simultaneous evaluation (multivariate evaluation) of multiple outcomes.

Results Data integrity The raw data were entered into six Excel spreadsheets, two for each of the three data waves (the 1-week, the 9month and the 18-month). The two data sheets for each wave were imported and compared. The initial consistency rates were 99.72%, 97.3% and 98.6% for the three waves, respectively. All inconsistent data were eliminated with two iterations of corrections. Attrition Sixty-five subjects with LBP volunteered for this investigation. Three subjects, all female, were excluded from participation, one because of previous McKenzie therapy, and two had previously read TYOB. As with most longitudinal studies, loss to follow-up is a concern. Of the 62 subjects in this study, 14 could not be reached with repeated attempts by phone for either the 9or 18-month follow-ups, or both. Comparing these 14 with the 48 who participated in the full follow-up process resulted in no significant differences in age (p⬍.78), gender (p⬍.15), education level (p⬍.70), length of time to read the book (p⬍.81), number of painful episodes (p⬍.74), pain severity (p⬍.33), use of the health-care system (p⬍.12) or comprehension of the material in the book (p⬍.27). No predictor reached statistical significance when using logistic regression to predict loss to follow-up. Thus, no systematic factors associated with attrition were observed, although this remains relatively weak evidence that attrition was in fact random.

Demographics Of the 62 eligible subjects, 35 (56%) were female and 27 (44%) were male. Average age was 42.4 years, ranging from 20 to 70 years of age. All had earned a high school diploma (high school, 30%; college, 39%; postgraduate, 31%). Mean duration of pain was 10.4 years with only two subjects being symptomatic for less than 15 months. Subjects reported a mean of 4.1 episodes of LBP the previous year, with an overall mean pain magnitude score of 1.3 based on a 0 to 3 ordinal scale (0⫽no pain, 1⫽mild pain, 2⫽moderate pain, 3⫽severe pain). Health-care utilization, based on subject’s report of seeking care for their LBP, is summarized in Fig. 1, which indicates, first, that this sample of patients with chronic low back troubles sought care from a wide variety of health-care providers and, second, that general practitioners, chiropractors and physical therapists were the most commonly sought out practitioners. The average number of providers was 2.45⫾1.81 and ranged from 0 to 10. Personal demographics, with two exceptions, were not significantly related or predictive of other demographics or health status. Age was positively correlated with duration of pain, r⫽.30, p⬍.02, and average number of episodes per year was related to gender, where women reported more episodes than men (5.51⫾5.83 compared with 2.63⫾2.27, p⬍.02). Health status measures were not as highly intercorrelated as might be expected, although pain duration was positively related to health-care utilization, r⫽.36, p⬍.004. Subject’s reactions to TYOB After reading the book, most subjects indicated that the book content included information new to them, with 29% indicating 0% to 24% of the material was new, 21% indicating that 25% to 49% of the material was new, 40% indicating that 50% to 74% of the material was new and 10% indicating that 75% or more of the material was new. Text comprehension was evaluated by administering a 25-item true/false test at the 1-week follow-up. The average

Fig. 1. Summary of history of medical system contacts for studied subjects.

B.E. Udermann et al. / The Spine Journal 4 (2004) 425–435

number of questions answered correctly was 19.72⫾2.88, where scores ranged from 12 to 24. Test performance was not related to the time it took to read the book, r⫽.02 (p⬍.85), nor to any of the personal or health status demographics. Opinions regarding the text were evaluated using 18 positively worded statements regarding text content, style and effects on behavior, with subject agreement to each rated on a five-point Likert agreement scale (1⫽strongly disagree, 2⫽disagree, 3⫽neutral, 4⫽agree, and 5⫽strongly agree). The averaged agreement with the positively worded statements of 4.21⫾.41, in conjunction with the coefficient alpha internal consistency index of .87 indicated that subjects reported strongly consistent agreement with the positive statements regarding the text. Fig. 2 summarizes the pattern of responses for each of the 18 items. At 1 week: 98% agreed or strongly agreed that the book’s content taught that “Self-treatment gives better long-term management of back problems than any other form of treatment”; 86% reported that they agreed or strongly agreed that they were confident in their ability to effectively self-treat their own back pain; 90% stated they agreed or strongly agreed that management of their LBP was their responsibility; 95% agreed or strongly agreed that they would use the book as a reference for both self-treating and preventing future acute episodes; 94% agreed or strongly agreed that the book had enhanced their knowledge of the origin and cause of LBP; and 76% percent agreed or strongly agreed that they could confidently interpret the significance of changes in their pain intensity and location. Open-ended responses to the request to “Please share with us any other thoughts or opinions you have regarding

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the book” were coded as summarized in Table 1. The request elicited 73 comments: 89.1% were positive comments of which 14 (19.2%) regarded style, 26 (35.6%) regarded content, 7 (9.6%) regarded exercise, 8 (11%) regarded posture and 10 (13.7%) regarded activities taken as a result of reading the book. The remaining 10.9% of the comments were negative, of which 5 (6.8%) regarded style and 3 (4.1%) regarded content. Two of the three negative content comments concerned issues-associated judgments as to when to seek professional help associated with acute LBP onset rather than to treat oneself. The other negative comment concerned worry that the book was designed to sell the reader products, such as a lumbar roll. Compliance Compliance was evaluated based on subject’s self-report regarding exercise performance and use of posture strategies. At the 9-month follow-up, 45 of 48 subjects (93.75%) reported that they had tried the exercises. Of those 45, 41 (91.11%) reported they were still doing them (ie, complying), with 32 (71.1%) performing only extension exercises, four (8.98%) only flexion exercises and nine (20%) both extension and flexion exercises. Because the book taught self-selection of exercises based on pain responses to specific movements, the diversity in the types of exercises reported may reflect a measure of compliance in both performing the self-assessment as directed and in self-selection of treatment exercises based on the assessment pain response findings. Regarding compliance with posture, 41 of 48 subjects (85.42%) followed at 9 months reported that they were still focusing on posture because of what they had learned from the book. Also at the 9-month follow-up, 36 of the 48 subjects (75%) reported continued compliance regarding both exercise and posture. At the 18-month follow-up, 43 of the 48 subjects followed (89.58%) reported that they were still performing their exercises. Of the 8 subjects who had previously reported noncompliance at 9 months, 2 still reported noncompliance at 18 months, with the other 6 now reporting compliance with the exercises. Only 3 who reported compliance at 9 months indicated they were no longer compliant at 18 months. Exercise self-selection

Fig. 2. Subjects’ perceptions and attitudes regarding the content, style and philosophy of the Treat Your Own Back text. LBP⫽low back pain; Tx⫽ treatment.

Of the 43 reporting exercise continuation, 28 (65.11%) reported performing extension exercises only, 3 (6.98%) flexion exercises only and 12 (27.91%) reported performing both extension and flexion exercises. The diversity in the types of exercise selected was therefore still apparent after 18 months, again suggesting subjects chose their own direction of exercise for self-treatment. Regarding compliance with posture, at the 18-month follow-up, 47 of the 48 subjects (97.92%) reported that they were still focusing on posture strategies. Only 1 subject had previously reported compliance at 9 months and reported

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noncompliance at 18 months, and 7 who reported noncompliance at 9 months indicated compliance with strategies at 18 months. Overall, of the 48 subjects followed up at both 9 and 18 months, 33 (68.75%) were fully compliant regarding both exercising and focusing on posture at both follow-up intervals; 37 (77.08%) were fully compliant regarding exercise at both follow-up intervals; 40 (83.33%) were fully compliant regarding posture at both follow-up intervals and only 2 (4.17%) reported that they were not compliant with exercise or posture at either of the follow-up intervals. In addition, at the 18-month follow-up, 33 of the 48 (68.75%) reported that they used the book as a reference to help them control their LBP. Treatment efficacy With a 22.58% loss to follow-up, even though no systematic factors associated with this loss were observed, it was decided to evaluate outcomes under three different models for handling attrition or loss to follow-up: 1) a complete-data model (N⫽48), where subjects with data at all three intervals were used; 2) a best-guess model (N⫽62), where missing values for the other 14 subjects at the 9- and 18-month intervals were estimated based on variables available from the 1-week data and 3) a worst-case model (N⫽62), where missing data at 9 and 18 months for the pain magnitude and perceived benefit scores were coded with the worst-case score (ie, 3 for pain magnitude and 0 for perceived benefit) and the number of painful episodes was coded with the 1week value adjusted from a 12-month to a 9-month interval to be consistent across the three assessments. The distributions of these three outcomes under each of the three models used to handle attrition are summarized in Table 2. The entire series of analyses were done separately for the complete-data, the best-guess and the worst-case attritionhandling models. The one-way multivariate analyses of the three outcomes (ie, pain magnitude, number of LBP episodes and perceived benefit) demonstrated significant assessment time effects across all three attrition-handling models, Wilks’ lambda⫽.338, F6, 184⫽22.05, p⬍.0001; Wilks’ lambda⫽ .331, F6, 240⫽29.56, p⬍.0001; and Wilks’ lambda⫽.693, F6, 240⫽8.04, p⬍.0001, for the complete-data, best-guess and worse-case models, respectively. Follow-up univariate ANOVAs for each outcome were generally similar across the three attrition-handling models. For the sake of brevity, only the worst-case data model results will be reported, although the patterns of means for all three models are included in the figures. For the worst-case model, significant assessment time main effects were also observed for all three outcomes, F2, 185⫽8.55, p⬍.0003, F2, 185⫽23.20, p⬍.0001, and F2, 185⫽5.39, p⬍.0057, for the pain magnitude, episode frequency and perceived benefit outcomes, respectively. The patterns of means for each attrition-handling model are summarized in Figs. 3, 4 and 5 for the pain magnitude,

episode frequency and perceived benefit outcomes, respectively. Fig. 3 indicates that average pain magnitude decreased significantly from 1-week to 9-month follow-up, and this decrease was maintained at 18-month follow-up; Fig. 4 presents a similar pattern of improvement regarding number of episodes per 9-month period, with even more improvement from the 9- to the 18-month follow-up; Fig. 5 also provides a consistent pattern, with pain reduction from baseline significantly different from 1-week to 9-month followup with slight additional improvement from 9- to 18-month follow-up, at least for the best-guess and worst-case models. The repeated measures categorical data modeling techniques used to evaluate the time effect for the pain magnitude and perceived benefit criteria resulted in statistically significant results, well beyond the .05 Type I error rate set for the study. Therefore, the parametric interpretations of these results were used.

Discussion This study was prompted by 1) the almost universal use of patient education as an initial or at least an ancillary step in the treatment of patients presenting with LBP, 2) the relative dearth of studies evaluating the effectiveness of patient education and 3) the complete lack of support in the few existing studies for the efficacy of education in improving patients’ long-term health status. Although the individualized biomechanical approach presented in the TYOB book [7] represented a type of educational approach different from the other educational booklets studied, the prestudy expectation for demonstrating strong efficacy for the TYOB educational program was, at best, cautiously optimistic. Accordingly, this research was designed as a feasibility study, which in this case translated into a relatively inexpensive prospective longitudinal cohort design with straight forward patient self-report assessment of opinions regarding the treatment approach, compliance with treatment and changes in health demographics across time. If evidence supported the efficacy of the TYOB educational and treatment approach, then more controlled and comprehensive studies might follow. Such studies would be important because the large volume of patients presenting with low back troubles begs the need for an effective triage system. The results of this feasibility study were unexpectedly positive and suggestive of the effectiveness of the TYOB booklet in improving these subjects’ long-term health status. These improvements, in terms of less pain, less use of the medical system and overall perceived benefit from using the techniques in the book were maintained after 9 months of follow-up and often demonstrated additional improvement after 18 months of follow-up. These results beg three basic questions: 1) Was the TYOB truly efficacious? 2) Why did this educational program work when other educational booklets have not? 3) What are the rival explanations for the results of this study?

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Table 2 Summary of outcomes across follow-up intervals with three distinct approaches for handling sample attrition Approach to handling missing data due to attrition Delete missing cases (N⫽48)

Best-guess substitution (N⫽62)

Worst-case substitution (N⫽62)

Outcomes

Time

Scale

Frequency

Percent

Frequency

Percent

Frequency

Percent

Pain magnitude

1 week

None Mild Moderate Severe None Mild Moderate Severe None Mild Moderate Severe

0 34 12 2 30 16 2 0 36 8 4 0

0 70.8 25.0 4.2 62.5 33.3 4.2 0.0 75.0 16.7 8.3 0.0

0 47 12 3 43 16 3 0.0 49 9 4 0

0.0 75.8 19.4 4.8 69.4 25.8 4.8 0.0 79.0 14.5 6.5 0.0

0 47 12 3 31 16 2 13 41 9 4 8

0.0 75.8 19.4 4.8 50.0 25.8 3.2 21.0 66.1 14.5 6.5 12.9

0 1–2 3–5 6–9 10⫹ 0 1–2 3–5 6–9 10⫹ 0 1–2 3–5 6–9 10⫹

7 21 9 6 5 30 13 2 0 3 44 3 1 0 0

14.6 43.8 18.8 12.5 10.4 62.5 27.1 4.2 0.0 6.3 91.7 6.3 2.0 0 0

8 25 17 6 6 36 19 4 0 3 49 8 5 0 0

12.9 40.3 27.4 9.7 9.7 58.1 30.6 6.5 0.0 4.8 79.0 12.9 8.1 0.0 0.0

8 25 17 6 6 32 17 9 0 4 49 8 5 0 0

12.9 40.3 27.4 9.7 9.7 51.6 27.4 14.5 0.0 6.5 79.0 12.9 8.1 0.0 0.0

Yes No Yes No Yes No

26 22 40 8 40 8

54.2 45.8 83.3 16.7 83.3 16.7

32 30 46 16 50 12

51.6 49.4 74.2 25.8 80.6 19.4

32 30 41 21 46 16

51.6 49.4 66.1 33.9 74.2 25.8

9 months

18 months

Episode frequency (per 9 months)

1 week

9 months

18 months

Pain reduced (from baseline)

1 week 9 months 18 months

The argument for efficacy The unique method of assessment taught in TYOB has considerable credibility already with numerous studies reporting strong interexaminer reliability when this same assessment is carried out by a trained clinician [15–20]. Eliciting beneficial patterns of pain response, that is, prompt pain centralization or elimination of low back and/or leg pain, occurs very commonly [8,20–29] during this form of assessment: in 73% to 89% of acute patients [22,25,27] and 47% to 49% of chronic patients [23,26]. Six of these prospective studies also tracked subject outcomes, all reporting superior outcomes in these very subjects compared with those whose pain did not respond favorably (centralize) during assessment [21,22,25–28]. Further, in compliance with current evidence-based guidelines emphasizing the importance of addressing patients’ attitudes and fears in hopes of minimizing engagement in the health-care system, 1.81% (50 of 62) reported

that they were confident in their ability to effectively selftreat their own back pain; 2.90% (56 of 62) agreed that management of their LBP was their responsibility and 3.98% (61 of 62) agreed that the book taught “Self-treatment gives better long-term management of back problems than any other form of treatment.” To our knowledge, no other study of an educational book has measured these attitudinal outcomes. Interestingly, subjects did not all choose the same exercises for their self-treatment, reporting a 7-to-1 ratio of subjects choosing extension only (71%) versus flexion only (9%) exercises, with the remaining 20% choosing to perform both directions. That this may have been related to subjects’ differing self-assessment pain response findings is supported by a similar extension-to-flexion ratio (nearly 6:1), based on pain response reported in a randomized controlled trial of 147 subjects who underwent this same form of assessment, directed in-person by trained clinicians, rather than a book [8].

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Fig. 3. Changes in subject-reported pain magnitude at 1-week to 9-month and 18-month follow-ups reported separately for the complete, best-guess and worse-case attrition-handling models.

Comparison with “like” studies Five studies cited in the introduction shared a common focus on educational booklets but had differing aims and implementations. However, none of these studies evaluated long-term physical outcomes, such as pain magnitude, incidence of episodes and perceived benefit, and their shorter-term focus was not on compliance. Thus, no comparisons can be made with our findings. On the other hand, that

these other studies have shown little or no impact on readers’ pain or long-term satisfaction suggests that the long-term efficacy and continued improvement measured in this study may be related to the content of the book and high subject compliance with its instructions. Rival hypothesis This was an uncontrolled prospective longitudinal cohort design. Uncontrolled prospective longitudinal cohort designs

Fig. 4. Changes in subject-reported frequency of pain episodes at 1-week to 9-month and 18-month follow-ups reported separately for the complete, bestguess and worse-case attrition-handling.

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Fig. 5. Changes in subject-reported perceived benefit from the book at 1-week to 9-month and 18-month follow-ups reported separately for the complete, best-guess and worse-case attrition-handling models.

by their nature cannot provide strong evidence that the effects were necessarily the result of the treatment. In fact, even a single well-designed and implemented randomized controlled clinical trial would also be inadequate to demonstrate strong support for treatment efficacy. Strong support requires multiple replications. At least six classes of conditions can generate rival explanations for this study’s results based on the basic tenets of the scientific method: 1. History/maturation. This is the notion that specific events occurring during the longitudinal run of the study or processes with the patients in the study, such as growth or aging issues, might explain these results. The notion of a positive natural history for patients presenting with low back troubles supports this notion. However, given the fact that the average length of time these patients reported having low back troubles was more than 10 years, coupled with the generally held notion that patients with chronic low back troubles are substantially less likely to have a positive natural history, suggests that history is not a particularly viable rival explanation for the observed improvement. The 18-month follow-up might be a sufficient time period for maturation factors to explain these results, but 18 months is not generally considered a long time interval for an adult population with average age of 42.4 years and ranging from 20 to 70 years. 2. Testing/subject/researcher interaction. The notion of patient/researcher interaction affecting results comes in many flavors. The Hawthorne effect suggests that simply being in a study may have an effect. However,

this study did not have many of the features commonly associated with a Hawthorne effect, most noticeably, another group of “less fortunates” who were not selected to be in the study. A halo effect might be a contributing factor to the extent that the subjects in the study inferred from their interactions with the researchers that this booklet would be very effective. In addition, halo effects are thought to be more probable when the outcomes are impressionist and subjective, which fit the self-reported compliance and health history outcomes used in this study. Thus, a follow-up study would need to include more objective outcomes to guard against halo effects. Self-fulfilling prophecy may explain some portion of these results to the extent that patients’ responses on the 9- and 18-month followup telephone interviews were biased either by the patients’ responses because of their desire to provide the researcher what they thought was wanted, or by the researcher, based not on the nature of the questions themselves, but the way in which the questions were asked. However, the contact researcher had no prior history with these volunteer subjects, and was not a clinician, which would seem to weaken the likelihood of undue influence over subjects’ attitudes and, therefore, lessen the influence of self-fulfilling prophesy on the results. 3. Statistical regression. Statistical regression is a byproduct of unreliability in assessment, where the extreme scores at one time tend to move toward the center in subsequent assessments. The notion that

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some improvement from a low health status might be expected across time, however, does not support the pattern of results observed in this study, where scores shifted dramatically from 1-week to 9-month followup and then continued to show improvement, or at least lack of regression toward the mean, at the 18month follow-up. In fact, improvement far exceeded merely moving to the mean and then remained there. 4. Selection. Typically, selection is an obvious concern in study designs that feature multiple groups, where the concern is that assignment to groups was not effectively random. In a prospective longitudinal cohort design, the concern would be that patients might have been screened to create a cohort thought to be particularly susceptible to the treatment. Given the relatively long history of low back troubles and the copious use of the medical system by many of the patients who volunteered for this study, plus the initial loss of only three patients because of failure to meet study inclusion and exclusion criteria, this sample of patients seems to fit a profile of recalcitrance to treatment. On the other hand, this sample, drawn from a university town, where all in the sample reported at least a high school education, does suggest that comprehension of the material and subsequent ability to follow directions may be a factor in the high compliance observed, which in turn may be a factor in the success of the treatment. 5. Experimental mortality. Experimental mortality is often a major problem in longitudinal studies, especially those that include follow-ups as long as 18 months. These concerns were addressed in the analyses by comparing results from the full-data, the bestguess and the worst-case models for handling data attrition or experimental mortality. The lack of substantial differences across these three attrition handling models suggests that this source of error was not a viable explanation for the improvement in health status observed to have occurred and stabilized over time. 6. Interactions of the above effects. Basic notions that patient personal and health demographics might be associated with differential outcomes were explored in these data with no significant or potentially relevant results observed. However, the lack of substantial sample size in this study makes it difficult to establish whether subgroups based on the above factors might exist that would explain these effects. Another plausible reason for the high compliance observed with the TYOB, other than the positive attitude toward the material, is the rapid positive feedback from patients 1 week after reading the book who reported that following the advice in the book allowed them to identify exercises that positively affected their back pain symptoms immediately, or almost immediately. From the basic tenets of

learning and human motivation theories, positive reinforcement (reduction in painful stimuli) in close proximity with an action (doing a prescribed exercise) is likely to result in learning, defined as an increased tendency to do the action when in a similar (painful) circumstance. Similarly, from the motivational perspective, a positive motivational state is likely to arise when the message is received and reinforced that the noxious painful stimulus is not stable (it can be relieved) and is controllable by the patient (the patient can behave to cause the pain to be relieved). Limitations/future directions Although our subjects’ mean pain duration exceeded 10 years, their mean baseline pain intensity was 1.3 on a 0 to 3 scale. We therefore cannot generalize as to the impact the book would have on individuals with more severe pain. Unlike prior educational booklet research [5,10–13], this study was designed as a feasibility study in the context of a nonfunded doctoral thesis that significantly limited its scope. Efforts to contain study costs were essential and focused on three items: 1) avoiding randomization; 2) limiting outcomes to patient self-report of low back health status (ie, pain magnitude, pain recurrence and perceived benefit) and compliance in reading the book, plus following its suggestions; 3) relying on telephone interviews to gather long-term follow-up. A subsequent randomized controlled trial would require substantial funding support. Seventy percent of the participants in this study were college graduates. It is unknown how individuals with less education would respond to this educational booklet.

Conclusion The results of this study are consistent with what would be expected if the TYOB book were efficacious in helping readers decrease their own LBP and reduce the frequency of, or even eliminate, their recurrent episodes. Although rival explanations for these results are possible given the limitations of the study design, these explanations were not considered sufficiently strong to negate the possibility that the observed pattern of results supporting treatment efficacy were valid. Thus, this study offers strong support for the feasibility of conducting a randomized controlled clinical trial to assess this book’s efficacy to improve health status in subjects with LBP. The study design should include internal controls to minimize bias issues and consider a wider range of outcomes, including measures of pain, function, disability, patient satisfaction, utilization of health-care services and psychosocial measures.

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