Interpreting the Clinical Importance of Treatment Outcomes in Chronic Pain Clinical Trials: IMMPACT Recommendations

Statistical Methods for Health Care Research

Research studies focusing on the fear-avoidance model have expanded considerably since the review by Vlaeyen and Linton (Vlaeyen J. W. S. & Linton, S. J. (2000). Fear-avoidance and its consequences in chronic musculoskeletal pain: a state of the art. Pain, 85(3), 317--332). The fear-avoidance model is a cognitive-behavioral account that explains why a minority of acute low back pain sufferers develop a chronic pain problem. This paper reviews the current state of scientific evidence for the individual components of the model: pain severity, pain catastrophizing, attention to pain, escape/avoidance behavior, disability, disuse, and vulnerabilities. Furthermore, support for the contribution of pain-related fear in the inception of low back pain, the development of chronic low back pain from an acute episode, and the maintenance of enduring pain, will be highlighted. Finally, available evidence on recent clinical applications is provided, and unresolved issues that need further exploration are discussed.

The fear-avoidance model of musculoskeletal pain: current state of scientific evidence.

Condition-specific health status measures are commonly used as outcome measures in clinical trials and to assess patient progress in routine clinical practice. The expert panel that met to discuss this special issue of Spine recommended that, when possible, a condition-specific measure for back pain should be chosen from two widely used measures, the Roland–Morris Disability Questionnaire (RDQ) or the Oswestry Disability Index (ODI). These two measures have been used in a wide variety of situations over many years, and each is available in a number of languages. In this article, the authors describe these two instruments and provide evidence of their validity and reliability and some comparative results obtained with the use of the two questionnaires. The instruments themselves are included in the appendixes. When used in the forms reproduced in the appendixes, no permission is required from the authors or from Spine. Other back pain–specific health status measures are described by Kopec elsewhere in this edition of Spine.

The Roland-Morris Disability Questionnaire and the Oswestry Disability Questionnaire.

Study Design. Literature review, expert panel, and a workshop during the "VIII International Forum on Primary Care Research on Low Back Pain" (Amsterdam, June 2006). Objective. To develop practical guidance regarding the minimal important change (MIC) on frequently used measures of pain and functional status for low back pain. of Background Data. Empirical studies have tried to determine meaningful changes for back pain, using different methodologies. This has led to confusion about what change is clinically important for commonly used back pain outcome measures. Methods. This study covered the Visual Analogue Scale (0-100) and the Numerical Rating Scale (0-10) for pain and for function, the Roland Disability Questionnaire (0-24), the Oswestry Disability Index (0-100), and the Quebec Back Pain Disability Questionnaire (0-100). The literature was reviewed for empirical evidence. Additionally, experts and participants of the VIII International Forum on Primary Care Research on Low Back Pain were consulted to develop international consensus on clinical interpretation. Results. There was wide variation in study design and the methods used to estimate MICs, and in values found for MIC, where MIC is the improvement in clinical status of an individual patient. However, after discussion among experts and workshop participants a reasonable consensus was achieved. Proposed MIC values are: 15 for the Visual Analogue Scale, 2 for the Numerical Rating Scale, 5 for the Roland Disability Questionnaire, 10 for the Oswestry Disability Index, and 20 for the QBDQ. When the baseline score is taken into account, a 30% improvement was considered a useful threshold for identifying clinically meaningful improvement on each of these measures. Conclusion. For a range of commonly used back pain outcome measures, a 30% change from baseline may be considered clinically meaningful improvement when comparing before and after measures for individual patients. It is hoped that these proposals facilitate the use of these measures in clinical practice and the comparability of future studies. The proposed MIC values are not the final answer but offer a common starting point for future research.

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Interpreting change scores for pain and functional status in low back pain: towards international consensus regarding minimal important change.

This study examined the relations between disability, as measured by the Pain Disability Index (PDI) and self-efficacy, fear avoidance variables (kinesiophobia and catastrophizing), and pain intensity, using a prospective design. Two primary health care samples (n1=210; n2=161) of patients with subacute, chronic or recurring musculoskeletal pain completed sets of questionnaires at the beginning of a physiotherapy treatment period. Multiple hierarchial regression analyses showed that self-efficacy explained a considerably larger proportion of the variance in disability scores than the fear avoidance variables in the first sample. This finding was replicated in the second sample. Pain intensity explained a small, but significant proportion of the variance in disability scores in one sample only. Gender, age, and pain duration were not related to disability. These findings suggest that self-efficacy beliefs are more important determinants of disability than fear avoidance beliefs in primary health care patients with musculoskeletal pain. The findings also suggest that pain-related beliefs, such as self-efficacy and fear avoidance, in turn, are more important determinants of disability than pain intensity and pain duration in these patients.

Self-efficacy, fear avoidance, and pain intensity as predictors of disability in subacute and chronic musculoskeletal pain patients in primary health care

Objective: To compare two different home exercise programmes for patients with acute whiplash-associated disorders (WAD). A further aim was to describe the initial prognostic variables related to self-reported pain at six months follow-up.Design: A randomized treatment study with a follow-up period of six months.Settings: The study was undertaken in an orthopaedic clinic at a university hospital.Subjects: A total of 59 symptomatic (neck pain, stiffness, etc.) patients with acute whiplash injury.Interventions: Patients were randomized to a regular treatment group (RT group) and an additional-exercise treatment group (AT group).Main outcome measures: Pain Disability Index (PDI), Self-Efficacy Scale (SES), Coping Strategies Questionnaire (CSQ), neck range of motion (ROM), head posture, kinaesthetic sensibility, visual analogue scale (VAS).Results: Patients given an additional exercise did not improve more than patients with regular treatment. Only one CSQ item, ‘Ability to decrease pain', showed a significan...

Acute whiplash-associated disorders (WAD): the effects of early mobilization and prognostic factors in long-term symptomatology

Background: In many countries, a general shortage of nurses is a public health problem, and retention of nurses in active work is a challenge. The aim of this study was to ascertain whether the same individual factors, working conditions and health problems had led to increased probability of both leaving jobs and prolonged sickness absence in a cohort of Swedish nurses over a period of 3 years. Methods: A baseline questionnaire was answered by 2293 nurses, representing a response rate of 86%. Exposed and unexposed nurses were compared with regard to two outcomes. During the 3-year follow-up, exposed and unexposed nurses were compared with regard to two outcomes: resigning and having at least one sick leave spell that lasted 28 days or longer. Results: We found that 18% of the nurses left their employment, and 16% had sick leave spells ≥28 days. Work in geriatric care, being socially excluded by superiors and/or workmates, negative effects of organizational changes and poor self-rated general health were factors that increased the likelihood of both leaving jobs and long-term sick leave. Conclusions: The present results underline the importance of improving working conditions and supporting sustainable health in order to prevent high turnover and prolonged sick leave among nurses. Resigning and moving to another institution can be interpreted as a way to actively cope with an unhealthy work environment.

The same factors influence job turnover and long spells of sick leave—a 3-year follow-up of Swedish nurses

Aim To evaluate the effectiveness of an individually tailored oral health   educational programme for oral hygiene self-care in patients with   chronic periodontitis compared with the standard tr ...

The effectiveness of an individually tailored oral health educational programme on oral hygiene behaviour in patients with periodontal disease: a blinded randomized-controlled clinical trial (one-year follow-up).

In a nation-wide investigation, covering all the hearing centres in Sweden, a study was made of adaptation processes, subjective discomfort from tinnitus, subjective loudness of tinnitus and psychological complaints in 3372 subjects by means of a questionnaire The most important predictors of discomfort from and adaptation to tinnitus were found to be the controllability and the degree of maskability by external sounds, ie the subject's coping abilities or internal-external locus of control Increased control and masking effects from the environment imply a decrease in discomfort and better adaptation The most important predictor of worsened subjective loudness of tinnitus was the duration of the tinnitus That is, subjects who had had tinnitus for a longer time perceived the loudness as more intense The psychosomatic factors which most strongly predicted increased discomfort from and decreased tolerance to tinnitus were depression and insomnia These findings have theoretical and practical implications for the management and treatment of tinnitus

Per Lindberg

Papers

Self-efficacy, fear avoidance, and pain intensity as predictors of disability in subacute and chronic musculoskeletal pain patients in primary health care

Acute whiplash-associated disorders (WAD): the effects of early mobilization and prognostic factors in long-term symptomatology

The same factors influence job turnover and long spells of sick leave—a 3-year follow-up of Swedish nurses

The effectiveness of an individually tailored oral health educational programme on oral hygiene behaviour in patients with periodontal disease: a blinded randomized-controlled clinical trial (one-year follow-up).

Predictors of tinnitus discomfort, adaptation and subjective loudness.