Criterion validity of the International Physical Activity Questionnaire Short Form against activPAL in overweight and...

To evaluate the criterion validity and test-retest reliability of the Chinese version International Physical Activity Questionnaire-Short Form (cIPAQ-SF) for assessing sedentary behaviour and physical activity (PA) in overweight and obese Chinese adults, using activPAL as the reference.

A cross-sectional study was conducted at a Clinical Nutrition Clinic in China. Participants completed the cIPAQ-SF before and after wearing an activPAL for 7 consecutive days. Criterion validity was assessed using Pearson's/Spearman's correlation coefficients and Bland-Altman plots for sitting time (hours/day), moderate, vigorous and moderate-to-vigorous PA (MVPA) (min/week). Sensitivity and specificity evaluated the IPAQ-SF's accuracy in identifying those not engaging in any PA and those not meeting the PA recommendation (MVPA ≥150 min/week). Test-retest reliability was assessed using intraclass correlation (ICC).

Among 80 participants (age 33.9±7.3 years; body mass index 29.1±4.5 kg/m²), the IPAQ-SF demonstrated moderate criterion validity for sitting time (r=0.577 on weekdays, r=0.444 on weekends) and MVPA (ρ=0.451) compared with activPAL. It underestimated sitting time by 3.5 hours/day on weekdays and 2.9 hours/day on weekends. The cIPAQ-SF showed moderate-to-high sensitivity for correctly identifying individuals who were not engaging in any PA (53.6%-85.7%) or not meeting PA recommendations (93.8%), but its specificity was low to moderate (47.8%-73.7%) for PA engagement and meeting guidelines (55.2%). Test-retest reliability was moderate for sitting time (ICC=0.549-0.614) and poor to moderate for PA levels (ICC=0.453-0.592).

The IPAQ-SF demonstrates moderate validity and reliability in assessing sedentary behaviour and insufficient PA among overweight and obese Chinese adults. It can be used to identify physically inactive individuals for targeted interventions and monitor changes in sedentary behaviour.