There was no consistent relationship with factors such as disease-specific or generic instrument or the number of response options .
Negative changes were not associated with larger ESs .
Population -based estimation procedures and brief follow-up were associated with smaller ESs , and acute conditions with larger ESs .
Background .
A number of studies have computed the minimally important difference ( MID ) for health-related quality of life instruments .
To determine whether there is consistency in the magnitude of MID estimates from different instruments .
Measurement of fatigue. determining minimally important clinical differences.
The purpose was to determine the minimally important clinical difference ( MICD ) in fatigue as measured by the Profile of Mood States , Schwartz Cancer Fatigue Scale ( SCFS ) , General Fatigue Scale , and a 10-point single-item fatigue measure . The MICD is the smallest amount of change in a symptom ( e.g. , fatigue ) measure that signifies an important change in that symptom . Subjects rated the degree of change in their fatigue over 2 days on a Global Rating Scale . 103 patients were enrolled on this multisite prospect i ve repeated measures design . MICD was determined following established procedures at two time points . Statistically significant changes were observed for moderate and large changes in fatigue , but not for small changes . The scales were sensitive to increases in fatigue over time . The MICD , presented as mean change , for each scale and per item on each scale is : POMS = 5.6 , per item = 1.1 , SCFS = 5.0 , per item = 0.8 , GFS = 9.7 , per item = 1.0 , and the single item measure of fatigue was 2.4 points . This information may be useful in interpreting scale scores and planning studies using these measures
There was no consistent relationship with factors such as disease-specific or generic instrument or the number of response options .
Negative changes were not associated with larger ESs .
Population -based estimation procedures and brief follow-up were associated with smaller ESs , and acute conditions with larger ESs .
Background .
A number of studies have computed the minimally important difference ( MID ) for health-related quality of life instruments .
To determine whether there is consistency in the magnitude of MID estimates from different instruments .