Reliability and validity of the 7-day Physical Activity Recall interview in a Spanish population

The aim of this study was to assess the reliability and convergent validity of the 7-day Physical Activity Recall (7-day PAR) interview in a sample of the Spanish population. Valid 7-day PAR interviews were conducted and RT3 accelerometer measurements taken for 160 subjects from the primary care population aged 24-83, 75 men and 85 women. Two 7-day PAR interviews were conducted, with a one-week interval, with 147 of these participants. Test-retest reliability was assessed using intraclass correlation coefficients. Convergent validity between the 7-day PAR and the accelerometer data were examined using Spearman's correlation coefficients, and the kappa index of agreement was calculated. The 7-day PAR reliability coefficients were 0.68 (95%CI: 0.58-0.76) for total energy expenditure, 0.65 (95%CI: 0.54-0.73) for the activity dose, and 0.61 (95%CI: 0.50-0.70) and 0.75 (95%CI: 0.67-0.81) for time spent on moderate and vigorous-intensity activity, respectively. These coefficients ranged from 0.91 to 0.96 in participants who reported a typical week in both interviews. Convergent validity ranged from 0.25 for time spent on vigorous activity to 0.52 for the activity dose, and the kappa index was 0.43 (95%CI: 0.30-0.56). Reliability and convergent validity coefficients in the Spanish population were generally moderate and similar to those found in other studies.