Psychometric properties of three instruments to measure fatigue with myocardial infarction.

The purpose of this study was to evaluate the psychometric properties of three questionnaires to measure fatigue with myocardial infarction. The Fatigue Symptom Inventory Interference Scale, Profile of Moods States Fatigue subscale (POMS-F), and Short Form 36 (SF-36) Vitality Scale were completed during hospitalization (n = 116) and 30 days after hospital admission (n = 49). Moderate to strong correlations were found among each of these fatigue scales and between each fatigue scale and measures of other variables to include vigor, depressed mood, anxiety, and physical functioning. POMS-F scores decreased significantly at Time 2, but this decline in fatigue was not validated on the other fatigue scales. Patients' Time 1 scores reflected significantly more fatigue compared to published scores for healthy adults. The ability to discriminate between groups suggests that the instruments may be useful for identifying patients with cardiovascular risk factors who report clinically significant fatigue.