01928nas a2200205   4500000000100000008004100001100001600042700001800058700001400076700001600090700001700106700001400123700002100137245011700158250001500275300001100290490000700301520136800308020004601676       2012                            d1 aFerreira P.1 aNascimento D.1 aOstelo R.1 aHerbert Rob1 aLatimer Jane1 aSmeets R.1 aFerreira Manuela00aA critical review of methods used to determine the smallest worthwhile effect of interventions for low back pain  a2011/10/22  a253-610 v653 a<p>
OBJECTIVE: To critically and systematically review methods used to estimate the smallest worthwhile effect of interventions for nonspecific low back pain. STUDY DESIGN AND SETTING: A computerized search was conducted of MEDLINE, CINAHL, LILACS, and EMBASE up to May 2011. Studies were included if they were primary reports intended to measure the smallest worthwhile effect of a health intervention (although they did not need to use this terminology) for nonspecific low back pain. RESULTS: The search located 31 studies, which provided a total of 129 estimates of the smallest worthwhile effect. The estimates were given a variety of names, including the Minimum Clinically Important Difference, Minimum Important Difference, Minimum Worthwhile Reductions, and Minimum Important Change. Most estimates were obtained using anchor- or distribution-based methods. These methods are not (or not directly) based on patients' perceptions, are not intervention-specific, and are not formulated in terms of differences in outcomes with and without intervention. CONCLUSION: The methods used to estimate the smallest worthwhile effect of interventions for low back pain have important limitations. We recommend that the benefit-harm trade-off method be used to estimate the smallest worthwhile effects of intervention because it overcomes these limitations.
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