Validity and reliability of the Danish version of the pregnancy physical activity questionnaire to assess levels of physical activity during pregnancy

Introduction Physical inactivity during pregnancy is associated with complications on the mother and child. Thus, assessments of physical activity in pregnant women is relevant. The American validated questionnaire, Pregnancy Physical Activity Questionnaire (PPAQ), measures physical activity during pregnancy, and a translated Danish version of the questionnaire is needed. Objectives To translate the original version of PPAQ into Danish (PPAQ-DK) and to determine face and content validity, and reliability of PPAQ-DK in pregnant Danish women. Materials and methods PPAQ was translated into Danish through a systematic process. Subsequently, face and content validity was examined on pregnant women. PPAQ-DK was revised, and the test-retest reliability of PPAQ-DK was investigated in another sample of pregnant women, where the respondents completed the questionnaire twice with one week apart, using an Intraclass Correlation Coefficient (ICC). Internal consistency reliability was determined using Cronbach ' s alpha. Results The face validity of the original PPAQ was achieved by interviews of 10 pregnant women (age (mean +/- SD): 31.0 +/- 3.0 years; 50% in second and 50% in third trimester) and minor changes in the revised version of PPAQ-DK were performed. The content validity was accepted by an expert panel. In 66 pregnant women (aged 30.2 +/- 4.8 years; 16.7, 63.6, and 19.7% in first, second and third trimester, respectively), the ICC in the test-retest reliability was 0.79 (0.68-0.87) of the overall PPAQ score. The Cronbach's alpha in the internal consistency reliability analysis was 0.7 in the overall PPAQ score. Conclusions The PPAQ-DK is within acceptable reliability and is a valid and reliable tool to measure overall physical activity level of pregnant Danish women.