Test-Retest Reliability, Agreement and Criterion Validity of Three Questionnaires for the Assessment of Physical Activity and Sedentary Time in Patients with Myocardial Infarction.

Regular physical activity (PA) and limited sedentary time (SED) are highly recommended in international guidelines for patients after a myocardial infarction (MI). Data on PA and SED are often self-reported in clinical practice and, hence, reliable and valid questionnaires are crucial. This study aimed to assess the test-retest reliability, criterion validity and agreement of two PA and one SED questionnaire commonly used in clinical practice, developed by the Swedish National Board of Health and Welfare (BHW) and the Swedish national quality register SWEDEHEART. Data from 57 patients (mean age 66 ± 9.2 years, 42 males) was included in this multi-centre study. The patients answered three questionnaires on PA and SED at seven-day intervals and wore an accelerometer for seven days. Test-retest reliability, criterion validity and agreement were assessed using Spearman's rho and linearly weighted kappa. Test-retest reliability was moderate for three of the six-sub questions (k = 0.43-0.54) within the PA questionnaires. For criterion validity, the correlation was fair within three of the six sub-questions (r = 0.41-0.50) within the PA questionnaires. The SED questionnaire had low agreement (k = 0.12) and criterion validity (r = 0.30). The studied questionnaires for PA could be used in clinical practice as a screening tool and/or to evaluate the level of PA in patients with an MI. Future research is recommended to develop and/or evaluate SED questionnaires in patients with an MI.

Test-retest reliability and responsiveness to change of clinical tests of physical fitness in patients with acute coronary syndrome included in the SWEDEHEART register.

BACKGROUND: To maximise the benefits obtainable from exercise-based cardiac rehabilitation, an evaluation of physical fitness using reliable, clinically relevant tests is strongly recommended. Recently, objective tests of physical fitness have been implemented in the SWEDEHEART register. The reliability of these tests has, however, not been examined for patients with acute coronary syndrome. AIMS: The aim of this study was to assess the test-retest reliability and responsiveness to change of the symptom-limited bicycle ergometer test, the dynamic unilateral heel-lift test and the unilateral shoulder-flexion test in patients with acute coronary syndrome. METHODS: In a longitudinal study design, a total of 40 patients (mean age 63.8 ± 9.5 years, five women), with ACS, aged < 75 years, were included at a university hospital in Sweden. The intra-class correlation coefficient (ICC) with a 95% confidence interval, standard error of measurement (SEM) and responsiveness in terms of the minimal detectable change were calculated. RESULTS: Excellent reliability was found, showing ICC values of 0.98 (0.96-0.99), SEM 4.71 for the bicycle ergometer test, ICC 0.87 (0.75-0.93), SEM 4.62 for the shoulder-flexion test and ICC 0.84 (0.71-0.91), SEM 2.24 for the heel-lift test. The minimal detectable change was 13 W, 13 and 6 repetitions for the bicycle ergometer test, shoulder-flexion and heel-lift tests respectively. CONCLUSIONS: The test-retest reliability of clinical tests evaluating physical fitness in patients with acute coronary syndrome included in the SWEDEHEART register was excellent. This makes the future comparison and evaluation of treatment effects in large unselected clinical populations of acute coronary syndrome possible.