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 .
Defining the minimum level of detectable change for the Roland-Morris questionnaire.
BACKGROUND AND PURPOSE The Rol and -Morris Question naire ( RMQ ) is a self-administered disability measure in which greater levels of disability are reflected by higher numbers on a 24-point scale . The RMQ has been shown to yield reliable measurements , which are valid for inferring the level of disability , and to be sensitive to change over time for groups of patients with low back pain . Little is known about the usefulness of this instrument in aiding decision making regarding individual patients . The purpose of this study was to determine the minimum level of detectable change when the RMQ is applied to individual patients . SUBJECTS The study sample consisted of 60 out patients with low back pain . METHODS The RMQ was administered at the subjects ' initial visit and again 4 to 6 weeks later . Conditional st and ard errors of measurement ( CSEMs ) were computed for initial and follow-up RMQ scores , and these values were used to estimate the minimum level of detectable change . Results . Minimum levels of detectable change at the 90 % confidence level varied from 4 to 5 RMQ points . CONCLUSION AND DISCUSSION The magnitude of CSEMs is sufficiently small to detect change in patients with initial scores in the central portion of the scale ( 4 - 20 RMQ points ) ; however , the magnitude is too large to detect improvement in patients with scores of less than 4 and deterioration in patients who have scores greater than 20
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 .