Reporting Quality Assessment Of Evidence And Time-series Analysis On Health Effects Of Air Pollution And Extreme Temperature

Background:Air pollution and extreme temperature posed serious threat to human health,which are major challenges to society.To enhance the response to climate change,researchers have produced a series of evidence（guidelines and systematic reviews）on health effects of air pollution and extreme temperature.The reporting quality of evidence helps present research evidence clearly,transparently,and completely.It can improve the generalizability of evidence.However,the reporting quality of evidence on the health effects of air pollution and extreme temperatures currently are unclear,which brings difficulties for policymakers and researchers in screening and using high-quality evidence.Objective:（1）To assess the reporting quality of guidelines on air pollution and extreme temperature;（2）to assess the reporting quality of SR/MAs on air pollution and extreme temperature;（3）to plot the evidence mapping for health effects of air pollution and extreme temperatures,and produce time-series evidence based on the research gaps of evidence mapping.Methods:Reporting guidelines are a checklist to help authors in reporting specific types of research based on clear methodology.Thus,we used different report guidelines to assess the reporting quality:1)World Health Organization（WHO）,National Institute for Health and Care Excellence（NICE）,Guidelines International Network（GIN）,Scottish Intercollegiate Guidelines Network（SIGN）and three databases（Pub Med,CNKI and CBM）were systematically searched.RIGHT was used to assess the reporting quality of included guidelines.2)Pub Med,Embase,the Cumulative Index to Nursing Allied Health Literature（CINAHL）,the Cochrane Library,Web of Science,China National Knowledge Infrastructure（CNKI）and China Biology Medicine disc（CBM）were systematically searched.SR/MAs for health effects of air pollution and extreme temperatures are included.PRISMA was chosen to evaluate the reporting quality of SR/Mas.Evidence mapping was plotted by Origin and evidence gaps were explored.3)Based on the research gaps identified by the evidence map,we used generalized additive models（GAMs）to analyze the health effects of the interactive effect between air pollution and temperature extremes in Beijing.Analyzing the changes in health risks of interactive effects of pre-post Air Pollution Prevention and Control Action Plan and exploring the susceptible populations in Beijing.Results:（1）A total of 12 guidelines on the health effects of air pollution and extreme temperatures were included:（1）11 guidelines were developed by WHO and 1was developed by NICE;（2）Only 7 guidelines reported as a guideline in the title,and no guideline reported the role of funder;（3）The extreme temperatures guidelines were not reported the areas of“review and quality assurance”and“funding and declaration and management of interests”.（2）340 SR/MAs were included in the evidence mapping:（1）the analysis of reporting quality assessment showed that only 39.1%of included studies were relatively complete,only 21.2%reported study protocol and registration,49.7%reported the method to assess the existence of bias in individual studies,41.7%reported the risk of bias for intra-study,and 47.4%reported the risk of bias for inter-study;（2）the reporting quality of air pollution SR/MAs was better than that of temperature,and statistically different at the method of assessing the risk of bias（55.0%/35.3%）and the assessment results of the risk of bias（46.4%/28.2%）.（3）246 SR/MAs on pollutants,87on temperature changes,and 7 on the interactions between air pollution and extreme temperatures.Evidence mapping showed that evidence was mainly focused on the effects of particulate matter on circulatory and respiratory diseases,and the number of evidence about black carbon（BC）was less.（3）The time-series analysis on health effects of the interactive effects between air pollution and extreme temperatures indicated that（1）After implementation of decarbonization policy,reductions were noted in non-accidental mortality（RR=1.064per 10μg/m³,95%CI:1.047,1.081）,circulatory mortality（RR=1.068 per 10μg/m³,95%CI:1.045,1.091）and respiratory mortality（RR=1.148 per 10μg/m³,95%CI:1.102,1.197）related to BC.And the association was more pronounced on cold days.（2）Higher risks of the impact of BC on respiratory diseases were observed in females（RR=1.360per 10μg/m³,95%CI:1.237,1.495）.Conclusions:（1）The reporting quality of guidelines in the areas of"evidence"and"recommendations",“review and quality assurance”and“funding and declaration and management of interests”need to be further improved,particular emphasis on“reported as a guideline in the title”and“the role of funder”.The reporting quality of SR/MAs on air pollution was better than extreme temperatures,and both have major shortcomings in the“registration of protocols”and“assessment and interpretation of risk of bias”.We recommend developing reporting guidances for guidelines and SR/MAs on health effects of air pollutants and extreme temperatures.（2）Evidence mapping showed that evidence was mainly focused on pollutants.The effects of pollutants on cancer and congenital malformations were new research hotspots.Meanwhile,evidences on tumor,mental and behavioral disorders need to be further strengthened.However,the evidence of health effects on BC,extreme temperature,and the interactive effects between air pollution and extreme temperatures were limited.（3）The health risk of BC on all-cause mortality,respiratory and circulatory mortalities during extreme low temperatures were higher in Beijing.Furthermore,compared with PM_2.5,BC posed a greater disease risk and the effectiveness of the decarbonization policy was more obvious.We recommend the government furtherly consider high-risk populations and pollutants in formulating decarbonization policies,and improve population health by atmospheric management.