Absolute MCID was strongly associated with baseline pain , explaining approximately two-thirds of the variation , and to a lesser degree with the operational definition of minimum pain relief and clinical condition .
MCID  for chronic pain relief vary considerably .
Baseline pain is strongly associated with absolute , but not relative , measures .
To a much lesser degree , MCID is also influenced by the operational definition of relevant pain relief and possibly by clinical condition .
BACKGROUND The minimum clinical ly important difference ( MCID ) is used to interpret the relevance of treatment effects , e.g. , when developing clinical guidelines , evaluating trial results or planning sample sizes .
There is currently no agreement on an appropriate MCID in chronic pain and little is known about which context ual factors cause variation .
METHODS This is a systematic review .
Defining substantial clinical benefit following lumbar spine arthrodesis.
BACKGROUND Vali date d health-related quality -of-life measures have become important st and ards in the evaluation of the outcomes of lumbar spine surgery . However , there are few well-defined criteria for clinical success based on these measures . The minimum clinical ly important difference is an important demarcation , but it could be considered a floor value rather than a goal in defining clinical success . Therefore , we sought to define thresholds of substantial clinical benefit for commonly used health-related quality -of-life measures following lumbar spine arthrodesis . METHODS Prospect ively collected preoperative and one-year postoperative health-related quality -of-life measures from 357 patients who were managed with lumbar spine arthrodesis for the treatment of degenerative conditions were identified . C and i date substantial clinical benefit thresholds for the Short Form-36 physical component score , Oswestry Disability Index , and back and leg pain numeric rating scales were identified with use of receiver operating characteristic curve analysis . Receiver operating characteristic curves were used to discriminate between patients who reported being " much better " or " about the same " with use of the vali date d Short Form-36 health transition item and between those who reported being " mostly satisfied " or " unsure " with use of a nonvali date d but more surgery-specific satisfaction-with- results survey . For each health-related quality -of-life measure , three response parameters were used : net change , percent change , and raw score at the time of the one-year follow-up . RESULTS Substantial clinical benefit thresholds for the Short Form-36 physical component score were a 6.2-point net improvement , a 19.4 % improvement , or a final raw score of > or = 35.1 points . Substantial clinical benefit thresholds for the Oswestry Disability Index were an 18.8-point net improvement , a 36.8 % improvement , or a final raw score of < 31.3 points . Substantial clinical benefit thresholds for the back pain and leg pain numeric rating scales were a 2.5-point net improvement or a final raw score of < 3.5 points . Substantial clinical benefit thresholds for percent change were 41.4 % for the back pain numeric rating scale and 38.8 % for the leg pain numeric rating scale . CONCLUSIONS We believe that thresholds of substantial clinical benefit for commonly used health-related quality -of-life measures following lumbar spine arthrodesis are important as they describe a magnitude of change that the patient recognizes as a major improvement
Absolute MCID was strongly associated with baseline pain , explaining approximately two-thirds of the variation , and to a lesser degree with the operational definition of minimum pain relief and clinical condition .
MCID  for chronic pain relief vary considerably .
Baseline pain is strongly associated with absolute , but not relative , measures .
To a much lesser degree , MCID is also influenced by the operational definition of relevant pain relief and possibly by clinical condition .
BACKGROUND The minimum clinical ly important difference ( MCID ) is used to interpret the relevance of treatment effects , e.g. , when developing clinical guidelines , evaluating trial results or planning sample sizes .
There is currently no agreement on an appropriate MCID in chronic pain and little is known about which context ual factors cause variation .
METHODS This is a systematic review .