Background: The International Physical Activity Questionnaire - Short Form (IPAQ-SF) has been recommended as a cost-effective method to assess physical activity. Several studies validating the IPAQ-SF have been conducted with differing results, but no systematic review of these studies has been reported. Methods: The keywords "IPAQ", "validation", and "validity" were searched in PubMed and Scopus. Studies published in English that validated the IPAQ-SF against an objective physical activity measuring device, doubly labeled water, or an objective fitness measure were included. Results: Twenty-three validation studies were included in this review. There was a great deal of variability in the methods used across studies, but the results were largely similar. Correlations between the total physical activity level measured by the IPAQ-SF and objective standards ranged from 0.09 to 0.39; none reached the minimal acceptable standard in the literature (0.50 for objective activity measuring devices, 0.40 for fitness measures). Correlations between sections of the IPAQ-SF for vigorous activity or moderate activity level/walking and an objective standard showed even greater variability (-0.18 to 0.76), yet several reached the minimal acceptable standard. Only six studies provided comparisons between physical activity levels derived from the IPAQ-SF and those obtained from objective criterion. In most studies the IPAQ-SF overestimated physical activity level by 36 to 173 percent; one study underestimated by 28 percent. Conclusions: The correlation between the IPAQ-SF and objective measures of activity or fitness in the large majority of studies was lower than the acceptable standard. Furthermore, the IPAQ-SF typically overestimated physical activity as measured by objective criterion by an average of 84 percent. Hence, the evidence to support the use of the IPAQ-SF as an indicator of relative or absolute physical activity is weak.

The World Health Organization recommends strategies to improve urban design, public transportation, and recreation facilities to facilitate physical activity for non-communicable disease prevention for an increasingly urbanized global population. Most evidence supporting environmental associations with physical activity comes from single countries or regions with limited variation in urban form. This paper documents variation in comparable built environment features across countries from diverse regions. The International Physical Activity and the Environment Network (IPEN) study of adults aimed to measure the full range of variation in the built environment using geographic information systems (GIS) across 12 countries on 5 continents. Investigators in Australia, Belgium, Brazil, Colombia, the Czech Republic, Denmark, China, Mexico, New Zealand, Spain, the United Kingdom, and the United States followed a common research protocol to develop internationally comparable measures. Using detailed instructions, GIS-based measures included features such as walkability (i.e., residential density, street connectivity, mix of land uses), and access to public transit, parks, and private recreation facilities around each participant’s residential address using 1-km and 500-m street network buffers. Eleven of 12 countries and 15 cities had objective GIS data on built environment features. We observed a 38-fold difference in median residential densities, a 5-fold difference in median intersection densities and an 18-fold difference in median park densities. Hong Kong had the highest and North Shore, New Zealand had the lowest median walkability index values, representing a difference of 9 standard deviations in GIS-measured walkability. Results show that comparable measures can be created across a range of cultural settings revealing profound global differences in urban form relevant to physical activity. These measures allow cities to be ranked more precisely than previously possible. The highly variable measures of urban form will be used to explain individuals’ physical activity, sedentary behaviors, body mass index, and other health outcomes on an international basis. Present measures provide the ability to estimate dose–response relationships from projected changes to the built environment that would otherwise be impossible.

This study investigated the performance of the portable Cortex Metamax 3B (MM3B) automated gas analysis system during both simulated and human exercise using adolescents. Repeated measures using a Gas Exchange System Validator (GESV) across a range of simulated metabolic rates, showed the MM3B to be adequately reliable (both percentage errors, and percentage technical error of measurements <2%) for measuring expired ventilation (V _E), oxygen consumption (VO₂), and carbon dioxide production (VCO₂). Over a 3 h period, the MM3B was shown to be acceptably stable in measuring gas fractions, as well as V _E, VO₂, and VCO₂ generated by the GESV, especially at moderate and high metabolic rates (drifts <2% and of minor physiological significance). Using eight healthy adolescents during rest, moderate, and vigorous cycle ergometry, the validity of the MM3B was tested against the primary criterion Douglas bag method (DBM) and a secondary criterion machine known to be accurate, the Jaeger Oxycon Pro system. No significant errors in V _E were noted, yet the MM3B significantly overestimated both VO₂ and VCO₂ by approximately 10–17% at moderate and vigorous exercise as compared to the DBM and at all exercise levels compared to the Oxycon Pro. No significant differences were seen in any metabolic variable between the two criterion systems (DBM and Oxycon Pro). It is concluded the MM3B produces acceptably stable and reliable results, but is not adequately valid during moderate and vigorous exercise without some further correction of VO₂ and VCO₂.

Objective: To investigate the reliability and the validity of the long format, Chinese version of the International Physical Activity Questionnaire (IPAQ-LC). Design: Cross-sectional study, examining the reliability and validity of the IPAQ-LC compared with a physical activity log (PA-log) and objective accelerometry. Setting: Self-reported physical activity (PA) in Hong Kong adults. Subjects: A total of eighty-three Chinese adults (forty-seven males, thirty-six females) were asked to wear an ActiTrainer accelerometer (MTI-ActiGraph, Fort Walton Beach, FL, USA) for >10 h over 7 d, to complete a PA-log at the end of each day and to complete the IPAQ-LC on day 8. On a sub-sample of twenty-eight adults the IPAQ-LC was also administered on day 11 to assess its reliability. Results: The IPAQ-LC had good test–retest reliability for grouped activities, with intra-class correlation coefficients ranging from 0·74 to 0·97 for vigorous, moderate, walking and total PA, with between-test effect sizes that were small (<0·49). The Spearman correlation coefficients were statistically significant for vigorous PA (r = 0·28), moderate + walking PA (r = 0·27), as well as overall PA (r = 0·35), when compared with the accelerometry-based criterion measures, but none of the IPAQ activity categories correlated significantly with the PA-log. In absolute units, only the IPAQ light and overall PA did not differ significantly from the accelerometry measures, yet overall PA was able to faithfully discriminate between quartiles of PA (P = 0·019) when compared to accelerometry. Conclusions: The IPAQ-LC demonstrated adequate reliability and showed sufficient evidence of validity in assessing overall levels of habitual PA to be used on Hong Kong adults.

Background: The IPEN (International Physical Activity and Environment Network) Adult project seeks to conduct pooled analyses of associations of perceived neighborhood environment, as measured by the Neighborhood Environment Walkability Scale (NEWS) and its abbreviated version (NEWS-A), with physical activity using data from 12 countries. As IPEN countries used adapted versions of the NEWS/NEWS-A, this paper aimed to develop scoring protocols that maximize cross-country comparability in responses. This information is also highly relevant to non-IPEN studies employing the NEWS/NEWS-A, which is one of the most popular measures of perceived environment globally. Methods: The following countries participated in the IPEN Adult study: Australia, Belgium, Brazil, Colombia, Czech Republic, Denmark, Hong Kong, Mexico, New Zealand, Spain, the United Kingdom, and the United States. Participants (N = 14,305) were recruited from neighborhoods varying in walkability and socio-economic status. Countries collected data on the perceived environment using a self- or interviewer-administered version of the NEWS/NEWS-A. Confirmatory Factor Analysis (CFA) was used to derive comparable country-specific measurement models of the NEWS/NEWS-A. The level of correspondence between standard and alternative versions of the NEWS/NEWS-A factor-analyzable subscales was determined by estimating the correlations and mean standardized difference (Cohen’s d) between them using data from countries that had included items from both standard and alternative versions of the subscales. Results: Final country-specific measurement models of the NEWS/NEWS-A provided acceptable levels of fit to the data and shared the same factorial structure with six latent factors and two single items. The correspondence between the standard and alternative versions of subscales of Land use mix – access, Infrastructure and safety for walking/cycling, and Aesthetics was high. The Brazilian version of the Traffic safety subscale was highly, while the Australian and Belgian versions were marginally, comparable to the standard version. Single-item versions of the Street connectivity subscale used in Australia and Belgium showed marginally acceptable correspondence to the standard version. Conclusions: We have proposed country-specific modifications to the original scoring protocol of the NEWS/NEWS-A that enhance inter-country comparability. These modifications have yielded sufficiently equivalent measurement models of the NEWS/NEWS-A. Some inter-country discrepancies remain. These need to be considered when interpreting findings from different countries.