Background: To evaluate the sensitivity to change of three generic quality-of-life measures in patients after myocardial infarction (MI).
Methods: Patients admitted to the Coronary Care Unit of Royal Devon and Exeter Healthcare Trust over a 9-month period were selected on the basis of a first MI and under 80 years of age. Quality of life was assessed 6 weeks and 6 months after MI using the Sickness Impact Profile (SIP), Nottingham Health Profile (NHP), and McMaster Health Inventory Questionnaire (MHIQ). An index of whether these measures are sensitive to change over time was determined by dividing the mean change from 6 weeks to 6 months of each instrument subscale by the baseline standard deviation of that subscale. Values of 0.2, 0.5, and 0.8 and above represent modest, moderate, and good sensitivity, respectively.
Results: Eighty-eight patients completed and returned the quality-of-life measures at both 6 weeks and 6 months. Four SIP subscales achieved a sensitivity to change index of 0.20 to 0.50: body care and movement, emotional behavior, work, and eating. Other SIP, NHP, and MHIQ subscales showed sensitivity index values of less than 0.20. No sensitivity index values of 0.50 or more were observed.
Conclusions: During the period of this study, all three generic quality-of-life measures displayed only modest levels of sensitivity to change. Other quality-of-life measures need to be developed for the assessment of cardiac patients. This is particularly important when choosing suitable quality-of-life measures to assess cardiac rehabilitation.