Literature review, expert panel, and a workshop during the "VIII International Forum on Primary Care Research on Low Back Pain" (Amsterdam, June 2006). To develop practical guidance regarding the minimal important change (MIC) on frequently used measures of pain and functional status for low back pain. 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. 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. 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. 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.

Background The COSMIN checklist is a standardized tool for assessing the methodological quality of studies on measurement properties. It contains 9 boxes, each dealing with one measurement property, with 5–18 items per box about design aspects and statistical methods. Our aim was to develop a scoring system for the COSMIN checklist to calculate quality scores per measurement property when using the checklist in systematic reviews of measurement properties. Methods The scoring system was developed based on discussions among experts and testing of the scoring system on 46 articles from a systematic review. Four response options were defined for each COSMIN item (excellent, good, fair, and poor). A quality score per measurement property is obtained by taking the lowest rating of any item in a box (“worst score counts”). Results Specific criteria for excellent, good, fair, and poor quality for each COSMIN item are described. In defining the criteria, the “worst score counts” algorithm was taken into consideration. This means that only fatal flaws were defined as poor quality. The scores of the 46 articles show how the scoring system can be used to provide an overview of the methodological quality of studies included in a systematic review of measurement properties. Conclusions Based on experience in testing this scoring system on 46 articles, the COSMIN checklist with the proposed scoring system seems to be a useful tool for assessing the methodological quality of studies included in systematic reviews of measurement properties.

Objective To assess the long term effects of multidisciplinary biopsychosocial rehabilitation for patients with chronic low back pain. Design Systematic review and random effects meta-analysis of randomised controlled trials. Data sources Electronic searches of Cochrane Back Review Group Trials Register, CENTRAL, Medline, Embase, PsycINFO, and CINAHL databases up to February 2014, supplemented by hand searching of reference lists and forward citation tracking of included trials. Study selection criteria Trials published in full; participants with low back pain for more than three months; multidisciplinary rehabilitation involved a physical component and one or both of a psychological component or a social or work targeted component; multidisciplinary rehabilitation was delivered by healthcare professionals from at least two different professional backgrounds; multidisciplinary rehabilitation was compared with a non- multidisciplinary intervention. Results Forty one trials included a total of 6858 participants with a mean duration of pain of more than one year who often had failed previous treatment. Sixteen trials provided moderate quality evidence that multidisciplinary rehabilitation decreased pain (standardised mean difference 0.21, 95% confidence interval 0.04 to 0.37; equivalent to 0.5 points in a 10 point pain scale) and disability (0.23, 0.06 to 0.40; equivalent to 1.5 points in a 24 point Roland-Morris index) compared with usual care. Nineteen trials provided low quality evidence that multidisciplinary rehabilitation decreased pain (standardised mean difference 0.51, −0.01 to 1.04) and disability (0.68, 0.16 to 1.19) compared with physical treatments, but significant statistical heterogeneity across trials was present. Eight trials provided moderate quality evidence that multidisciplinary rehabilitation improves the odds of being at work one year after intervention (odds ratio 1.87, 95% confidence interval 1.39 to 2.53) compared with physical treatments. Seven trials provided moderate quality evidence that multidisciplinary rehabilitation does not improve the odds of being at work (odds ratio 1.04, 0.73 to 1.47) compared with usual care. Two trials that compared multidisciplinary rehabilitation with surgery found little difference in outcomes and an increased risk of adverse events with surgery. Conclusions Multidisciplinary biopsychosocial rehabilitation interventions were more effective than usual care (moderate quality evidence) and physical treatments (low quality evidence) in decreasing pain and disability in people with chronic low back pain. For work outcomes, multidisciplinary rehabilitation seems to be more effective than physical treatment but not more effective than usual care.

Changes in scores on health status questionnaires are difficult to interpret. Several methods to determine minimally important changes (MICs) have been proposed which can broadly be divided in distribution-based and anchor-based methods. Comparisons of these methods have led to insight into essential differences between these approaches. Some authors have tried to come to a uniform measure for the MIC, such as 0.5 standard deviation and the value of one standard error of measurement (SEM). Others have emphasized the diversity of MIC values, depending on the type of anchor, the definition of minimal importance on the anchor, and characteristics of the disease under study. A closer look makes clear that some distribution-based methods have been merely focused on minimally detectable changes. For assessing minimally important changes, anchor-based methods are preferred, as they include a definition of what is minimally important. Acknowledging the distinction between minimally detectable and minimally important changes is useful, not only to avoid confusion among MIC methods, but also to gain information on two important benchmarks on the scale of a health status measurement instrument. Appreciating the distinction, it becomes possible to judge whether the minimally detectable change of a measurement instrument is sufficiently small to detect minimally important changes.