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 .
Quality of life in patients with chronic obstructive pulmonary disease improves after rehabilitation at home.
We have developed a rehabilitation programme at home and have investigated its effects on quality of life ( QOL ) , lung function , and exercise tolerance in patients with chronic obstructive pulmonary disease ( COPD ) . We studied 43 patients with severe airflow obstruction : forced expiratory volume in one second ( FEV1 ) 1.3 + /- 0.4 l ( mean + /- SD ) , FEV1/inspiratory vital capacity ( IVC ) 37 + /- 7.9 % . After stratification , 28 patients were r and omly allocated in a home rehabilitation programme for 12 weeks . Fifteen patients in a control group received no rehabilitation . The rehabilitation group received physiotherapy by the local physiotherapist , and supervision by a nurse and a general practitioner .  Quality of life was assessed by the four dimensions of the Chronic Respiratory Question naire ( CRQ ) . We found a highly significant improvement in the rehabilitation group compared to the control group for the dimensions dyspnoea , emotion , and mastery . Lung function showed no changes in the rehabilitation group . The exercise tolerance improved significantly in the rehabilitation group compared to the control group . The improvement in quality of life was not correlated with the improvement in exercise tolerance . Rehabilitation of COPD patients at home may improve quality of life ; this improvement is not correlated with an improvement in lung function and exercise tolerance
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 .