Global impacts of non‑optimal temperature on respiratory health: a systematic review and meta‑analysis

The eligibility criteria for this umbrella review were structured by the population, exposure, comparator (s), outcomes, and study design (PECOS) statement: a) population—all kind of human; b) exposure—studies on temperature; c) comparators—studies reporting risk ratios (RR), odds ratios (OR), hazard ratios (HR), or beta coefficients for those exposed to lower levels of the exposures as matched to increasing degrees or for the risk of adverse respiratory health outcomes with clear increments of temperature; d) outcomes—studies on human health outcomes; e) study design—reviews of relevant quantitative observational epidemiologic research, including cohort, case-control, and cross-sectional studies, with or without the utilization of meta-analysis. The exclusion criteria were as follows: a) narrative reviews, letters, conference abstracts, and research protocols; b) examination of genetic or experimental studies in animals, in vitro, and in vivo; and c) focus on special study populations, such as occupational groups or assisted reproduction mothers. A tailored Office of Health Assessment and Translation (OHAT) tool was applied to conduct RoB evaluation , which is a modified criterion, including the following items: outcome, bias of confounding, exposure assessment, selective reporting, detection and exclusion bias, conflict of interest. The risk level was “high”, “probably high”, “probably low”, “low”.