Psychometric evaluation of the Timeline Followback for Exercise among college students

摘要

Objectives: Two separate studies assessed the psychometric properties of a retrospective behavioral measure adapted for exercise called the Timeline Followback for Exercise (TLFB-E). Study one examined criterion, convergent, and predictive validity. Study two examined test-retest reliability. Design: Validity data was collected at three time points (baseline, 2 months, and 6 months) as part of a randomized clinical trial on exercise engagement. Test-retest reliability was assessed via two participant interviews scheduled one month apart. Methods: Study one participants (N = 66) were college students 20.0 ± 1.4 yr. Validity of frequency, intensity, time, and type (FITT) of exercise as assessed on the TLFB-E was examined using Pearson r correlations with accelerometers, weekly exercise contracts between participants and researchers, question four of the College Alumni Questionnaire, and a health-related physical fitness battery. Study two participants were a different sample (N = 40) of college students 18.63 ± 1.0 yr. Pearson r correlations determined reliability of the TLFB-E for exercise frequency, intensity, and time. Kappa statistic determined reliability of the TLFB-E for type of exercise. Results: The TLFB-E displayed evidence of criterion validity when compared to accelerometers (r =.35 to.39) and evidence of convergent validity when compared to weekly exercise contracts (r =.65 to.80) and question four of the College Alumni Questionnaire (r =.06 to.75). The TLFB-E displayed evidence of modest to adequate test-retest reliability (r =.79 to.97) for exercise frequency, intensity, and time and moderate Kappa (k =.49) for exercise type. Conclusions: The TLFB-E produces evidence of reliable and valid scores among college students and improves upon other self-report, retrospective questionnaires by enabling daily collection of exercise FITT over a specified time period.