Concurrent and predictive validity of physical activity measurement items commonly used in clinical settings--data from SCAPIS pilot study

• Published in: BMC public health Vol. 15; no. 1; p. 978
• Main Authors: Ekblom, Örjan, Ekblom-Bak, Elin, Bolam, Kate A, Ekblom, Björn, Schmidt, Caroline, Söderberg, Stefan, Bergström, Göran, Börjesson, Mats
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 28-09-2015; BioMed Central
• Subjects: Accelerometer; Accelerometry; activity questionnaires; adults; Body Weights and Measures; cardiovascular-disease; criterion-related validity; Environmental & Occupational Health; Exercise; Female; Folkhälsovetenskap, global hälsa, socialmedicin och epidemiologi; Health aspects; health-care; Humans; individuals; Male; Measurement; Medical research; Medicin och hälsovetenskap; Medicin/Teknik; Medicine, Experimental; Medicine/Technology; Metabolic syndrome; Metabolic Syndrome - epidemiology; Middle Aged; Odds Ratio; Pilot Projects; Prediction; Public; Public health; Public Health, Global Health, Social Medicine and Epidemiology; Questionnaire; reliability; Reproducibility of Results; Risk; ROC Curve; Sedentary; sedentary behavior; Sedentary Lifestyle; Self Report - standards; Socioeconomic Factors; time; Time Factors
• ISSN: 1471-2458; 1471-2458
• DOI: 10.1186/s12889-015-2316-y

As the understanding of how different aspects of the physical activity (PA) pattern relate to health and disease, proper assessment is increasingly important. In clinical care, self-reports are the most commonly used assessment technique. However, systematic comparisons between questions regarding concurrent or criterion validity are rare, as are measures of predictive validity. The aim of the study was to examine the concurrent (using accelerometry as reference) and predictive validity (for metabolic syndrome) of five PA questions.
A sample of 948 middle-aged Swedish men and women reported their PA patterns via five different questions and wore an accelerometer (Actigraph GT3X) for a minimum of 4 days. Concurrent validity was assessed as correlations and ROC-analyses. Predictive validity was assessed using logistic regression, controlling for potential confounders.
Concurrent validity was low-to-moderate (r <0.35 and ROC AUC <0.7) with large misclassifications regarding time spent sitting/sedentary and in moderate-to vigorous PA. The predictive validity of the questions was good, and one question (PHAS) showed an 80 % decreased odds-ratio of having metabolic syndrome, after taking potential confounders into consideration.
In this mixed sample of adults, both concurrent and predictive validity vaired between items and between measures of the physical activity pattern. The PHAS and WALK items are proposed for assessment of adherence to PA recommendations.
Assessing PA patterns using self-report measures results in methodological problems when trying to predict individual risk for the metabolic syndrome, as the concurrent validity generally was low. However, several of the investigated questions may be useful for assessing risk at a group level, showing better predictive validity.