Comparison Of Moderate to Vigorous Physical Activity Assessed by Accelerometry and the GPPAQ

Background: The General Practice Physical Activity Questionnaire (GPPAQ) is a screening tool developed by the National Health Service for use by general practitioners to assess physical activity (PA) levels of patients during clinical visits. Presently, it is not well understood if the GPPAQ classifications (active, moderately active, moderately inactive and inactive) clearly differentiate PA status.

Purpose: To determine whether the GPPAQ accurately differentiates individuals into different activity categories by comparing it to objectively measured time spent in moderate to vigorous physical activity (MVPA).

Methods: A total of 41 subjects (16 men and 24 women, 49.6±19.8 yr) and 35 subjects (19 men and 15 women, 42.2±21.3 yr) were recruited from Muncie IN, USA and Worcestershire, UK, respectively. Subjects wore an ActiGraph GT3X+ accelerometer on their right hip for a minimum of 4 days with 10 hours of valid wear-time per day and completed the GPPAQ at the end of the observation week. Accelerometers were initialized in ActiLife v6.8.0 using 60Hz sampling rates and processed using a 60 second epoch. Subjects determined to be moderately inactive by the GPPAQ were placed in the inactive group for analyses due to low subject volume (n=7). Total time in MVPA and MVPA accumulated in bouts of ≥10 minutes were quantified by applying Sasaki et al. (2011) VM cutpoints (≥2690 activity counts/min). A one-way ANOVA was used to assess for mean differences in MVPA between PA groupings by the GPPAQ. Signifi cance was set at 0.05.

Results: There were no significant differences between active (n=35), moderately active (n=13), and moderately inactive/inactive (n=26) in total MVPA time (min/wk) (344.1±190.6 [range = 33.0 to 839.0], 322.1±175.6 [range = 115.0 to 662.0], and 319.4±157.4 [range = 74.0 to 690.0], respectively). Similarly, MVPA accumulated in bouts of ≥10 minutes (min/wk) (171.5±137.1 [range = 0 to 415.0], 134.8±89.9 [range = 28.0 to 349.0], 120.8±113.9 [range = 0 to 469.0, respectively) were not significantly different.

Conclusion: Findings demonstrate that the GPPAQ may not be able to accurately classify individuals into different activity categories. Thus, either modifications to the GPPAQ should be considered or clinicians may need to seek alternative physical activity assessment methods.