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 .
What Is a Meaningful Pain Reduction in Patients With Complex Regional Pain Syndrome Type 1?
Objective To investigate the degree of  pain reduction  in patients with complex regional pain syndrome type 1 ( CRPS 1 ) that can be defined as “ successful . ” Design All patients rated their pain on a visual analog scale ( VAS ; 0–10 ) before treatment and on three occasions after treatment , at 6 months , 1 year , and 2 years . Patients also rated a Global Perceived Effect  ( GPE ) for their pain relief at the same time periods . The GPE items were classified as “ successful ” or “ unsuccessful . ” The mean absolute and relative pain reduction ( using the VAS ) was calculated for both “ successful ” and “ unsuccessful ” GPE classifications for each time period . Sensitivity and specificity analyses were performed . Patients Sixty-one patients with CRPS 1 . Results The patients defined a relative pain reduction of 58 % ( SD , 23.4 ) or more as “ successful , ” whereas in “ successful ” and “ unsuccessful ” patient groups the pain was reduced significantly on the VAS . Furthermore , sensitivity and specificity analyses showed that a cut-off point of 50 % relative pain reduction and a 3-cm absolute pain reduction on the VAS have the highest likelihood that patients will report their treatment “ successful ” on the GPE . Conclusions Relative pain reduction of 50 % or more and an absolute pain reduction of at least 3 cm on the VAS are accurate in predicting a successful pain reduction after a given treatment
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 .