Our review revealed a great heterogeneity in definition , format , and values of what is considered a clinical ly relevant difference in pain in RCTs of analgesics , and st and ardizations are advisable
OBJECTIVE To describe the  pain decrease considered as clinical ly relevant when design ing a trial and reporting its results .
Measurement of health status. Ascertaining the minimal clinically important difference.
In recent years quality of life instruments have been featured as primary outcomes in many r and omized trials . One of the challenges facing the investigator using such measures is determining the significance of any differences observed , and communicating that significance to clinicians who will be applying the trial results . We have developed an approach to elucidating the significance of changes in score in quality of life instruments by comparing them to global ratings of change . Using this approach we have established a plausible range within which the minimal clinical ly important difference ( MCID ) falls . In three studies in which instruments measuring  dyspnea , fatigue , and emotional function in patients with chronic heart and lung disease were applied the MCID was represented by mean change in score of approximately 0.5 per item , when responses were presented on a seven point Likert scale . Furthermore , we have established ranges for changes in question naire scores that correspond to moderate and large changes in the domains of interest . This information will be useful in interpreting question naire scores , both in individuals and in groups of patients participating in controlled trials , and in the planning of new trials
Our review revealed a great heterogeneity in definition , format , and values of what is considered a clinical ly relevant difference in pain in RCTs of analgesics , and st and ardizations are advisable
OBJECTIVE To describe the  pain decrease considered as clinical ly relevant when design ing a trial and reporting its results .