Tools for measuring walking time make use of objective and subjective methods. One subjective approach is to administer physical activity questionnaires (PAQ), mainly because they are inexpensive and easy to give to large groups. The European Prospective Investigation into Cancer and Nutrition (EPIC) study has a brief PAQ (EPIC-PAQ) and includes one question referencing walking time. The objective of this study was to assess the validity of the question about time spent walking included in the EPIC-PAQ.
The sample included 200 older adults (113 women). To assess daily walking time, participants responded to the EPIC-PAQ in an interview and wore a portable gait analysis system and physical activity monitor for 48 consecutive hours in free-living condition.
Results indicated that the mean of bias between the EPIC-PAQ and objetive measurement was ?64.6 min/day. Also, the correlation was low compared to an objective measurement (rho = 0.196) and was positively correlated with the time spent at speeds below 2.5 mph but the correlation was low (slow walking rho = 0.154 and pace walking rho = 0.163).
The EPIC-PAQ shows low correlations with the objective measurement of walking time, that suggests it may be inaccurate and affecting the estimate of the EPIC-PAQ’s PA energy expenditure in this age group. 相似文献
BackgroundPhysical activity (PA) may have an impact on digestive-system cancer (DSC) by improving insulin sensitivity and anticancer immune function and by reducing the exposure of the digestive tract to carcinogens by stimulating gastrointestinal motility, thus reducing transit time. The current study aimed to determine the effect of PA on different types of DSC via a systematic review and meta-analysis.MethodsIn accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched for relevant studies in PubMed, Embase, Web of Science, Cochrane Library, and China National Knowledge Infrastructure. Using a random effects model, the relationship between PA and different types of DSC was analyzed.ResultsThe data used for meta-analysis were derived from 161 risk estimates in 47 studies involving 5,797,768 participants and 55,162 cases. We assessed the pooled associations between high vs. low PA levels and the risk of DSC (risk ratio (RR) = 0.82, 95% confidence interval (95%CI): 0.79–0.85), colon cancer (RR = 0.81, 95%CI: 0.76–0.87), rectal cancer (RR = 0.88, 95%CI: 0.80–0.98), colorectal cancer (RR = 0.77, 95%CI: 0.69–0.85), gallbladder cancer (RR = 0.79, 95%CI: 0.64–0.98), gastric cancer (RR = 0.83, 95%CI: 0.76–0.91), liver cancer (RR = 0.73, 0.60–0.89), oropharyngeal cancer (RR = 0.79, 95%CI: 0.72–0.87), and pancreatic cancer (RR = 0.85, 95%CI: 0.78–0.93). The findings were comparable between case-control studies (RR = 0.73, 95%CI: 0.68–0.78) and prospective cohort studies (RR = 0.88, 95%CI: 0.80–0.91). The meta-analysis of 9 studies reporting low, moderate, and high PA levels, with 17 risk estimates, showed that compared to low PA, moderate PA may also reduce the risk of DSC (RR = 0.89, 95%CI: 0.80–1.00), while compared to moderate PA, high PA seemed to slightly increase the risk of DSC, although the results were not statistically significant (RR = 1.11, 95%CI: 0.94–1.32). In addition, limited evidence from 5 studies suggested that meeting the international PA guidelines might not significantly reduce the risk of DSC (RR = 0.96, 95%CI: 0.91–1.02).ConclusionCompared to previous research, this systematic review has provided more comprehensive information about the inverse relationship between PA and DSC risk. The updated evidence from the current meta-analysis indicates that a moderate-to-high PA level is a common protective factor that can significantly lower the overall risk of DSC. However, the reduction rate for specific cancers may vary. In addition, limited evidence suggests that meeting the international PA guidelines might not significantly reduce the risk of DSC. Thus, future studies must be conducted to determine the optimal dosage, frequency, intensity, and duration of PA required to reduce DSC risk effectively. 相似文献