From analyses of individual patient data ( seven studies , 918 patients ) , we found baseline pain strongly associated with absolute , but not relative , MCID as patients with higher baseline pain needed larger pain reduction to perceive relief .
Conclusions The MCID in acute pain varied greatly between studies and was influenced by baseline pain , definitions of improved patients and study design .
Background The minimum clinical ly important difference ( MCID ) is used to interpret the clinical relevance of results reported by trials and meta-analyses as well as to plan sample sizes in new studies .
However , there is a lack of consensus about the size of MCID in acute pain , which is a core symptom affecting patients across many clinical conditions .
Validation and properties of the verbal numeric scale in children with acute pain
& NA ; Although the verbal numeric scale ( VNS ) is used frequently at patients ’ bedsides , it has never been formally vali date d in children with acute pain . In order to vali date this scale , a prospect i ve cohort study was performed in children between 8 and 17 years presenting to a pediatric emergency department ( ED ) with acute pain . Pain was grade d using the VNS , the visual analogue scale ( VAS ) , and the verbal rating scale ( VRS ) .  A second assessment was done before discharge . We determined a priori that in order to be valid , the VNS would need to : correlate with the VAS ( concurrent validity ) ; decrease after intervention to reduce pain ( construct validity ) ; and be associated with the VRS categories ( content validity ) . The VNS interchangeability with the VAS , its minimal clinical ly significant difference , and test – retest reliability were also determined . A total of 202 patients ( mean age : 12.2 ± 2.6 years ) were enrolled . The VNS correlated with the VAS : ric = 0.93 , p < 0.001 . There were differences in the VNS before versus after interventions ( p < 0.001 ) , and between VRS categories ( mild versus moderate , p < 0.001 ; moderate versus severe , p < 0.001 ) . The 95 % limits of agreement ( interchangeability ) between VNS/VAS were outside the a priori set limit of ±2.0 : −1.8 , 2.5 . The VNS minimal clinical ly significant difference was 1 . The VNS had good test – retest reliability with 95 % limits of agreement of −0.9 and 1.2 . In conclusion , the VNS  provides a valid and reliable scale to evaluate acute pain in children aged 8–17 years but is not interchangeable with the VAS
From analyses of individual patient data ( seven studies , 918 patients ) , we found baseline pain strongly associated with absolute , but not relative , MCID as patients with higher baseline pain needed larger pain reduction to perceive relief .
Conclusions The MCID in acute pain varied greatly between studies and was influenced by baseline pain , definitions of improved patients and study design .
Background The minimum clinical ly important difference ( MCID ) is used to interpret the clinical relevance of results reported by trials and meta-analyses as well as to plan sample sizes in new studies .
However , there is a lack of consensus about the size of MCID in acute pain , which is a core symptom affecting patients across many clinical conditions .