Table 2.

Characteristics of studies that examine the effect of meteorological factors on asthma admissions.

Author	Objective	Study design	Data source		Measures of effect			Study outcome		Quality
			Health data	Climate data	OR	RR	Count	EDV1	HA2
Abe et al. [6]	Investigate the relationship of weather conditions and asthma exacerbation	Time-series	Tokyo Fire Department, follow-up diagnostic data from emergency physicians	Japan Meteorological Agency	X			X		Good
Anderson et al. [14]	Investigate associations between asthma admissions and thunderstorms	Case control	Computerized hospital record	Met. Office and Cardiff Airport measurement site.			X		X	Fair
Buckley and Richardson [15]	Characterize the effect of temperature on EDVs for asthma	Case-crossover	Epidemiologic Collection Tool (NC DETECT)	State Climate Office of North Carolina	X			X		Fair
Delamater et al. [16]³	Investigate the relationships between air pollution, weather conditions, and asthma hospitalizations	Ecological	Healthcare Information Resource Center	Environmental Protection Agency (EPA)			X		X	Fair
Fitzgerald et al. [11]	Investigate whether prolonged periods of very cold temperatures are associated with an increased risk of hospitalization for asthma patients	Time-series	New York State Department of Health, Statewide Planning and Research Cooperative System (SPARCS)	National Center for Atmospheric Research			X		X	Fair
Grundstein et al. [17]	Examine the association between thunderstorm activity and asthma morbidity	Time-series	EDV database	Automated surface observing system station		X		X		Poor
Kunikullaya et al., 2017³	Determine the relationship between acute exacerbations of asthma and related HAs due to air pollution and meteorological conditions	Retrospective ecological time-series	Admission recorded by the hospital	Central laboratory of Karnataka State Pollution Control Board and meteorological department			X	X		Fair
Kwon et al. [18]³	Estimate the effect of climate factors and air pollution on asthma hospitalization	Case-crossover	Kangwon National University Hospital and Chuncheon Sacred Heart Hospital	Database of the Korea Meteorological Administration		X		X		Fair
Lam et al. [19]	Evaluate associations between asthma hospitalizations and meteorological factors in Hong Kong.	Time-series	Hospital authority	Single central monitoring station from the Hong Kong Observatory (HKO)			X		X	Fair
Qasem et al. [20]³	Explore which weather factors contribute to asthma hospitalization while controlling for pollen and spore level in the air in Kuwait	Retrospective time-series study	Medical records from two hospitals (Al-Rashid Allergy Center and Emergency Department, and Al-Sabah Hospital)	Kuwait Aviation/Meteorology Department			X		X	Fair
Qiu et al. [21]	Examine the health effects of environmental triggers on asthma	Longitudinal time-series	Hospital Authority Corporate Data Warehouse	Hong Kong Observatory			X	X		Fair
Rossi et al. [22]³	Evaluate the relationships between EDVs for asthma attacks and the meteorological, aerobiological, and chemical characteristics of the outdoor air	Time-series	University Central Hospital	Measured at the meteorological station in the city of Oulu			X	X		Fair
Soneja et al., 2016	Investigate the association between exposure to extreme heat and precipitation events and risk of hospitalization for asthma	Case-crossover	Maryland Department of Health and Mental Hygiene	National Climatic Data Center		X			X	Fair
Zhang et al. [9]	Evaluate the short-term effects of daily mean temperature on asthma HAs.	Time-series	Health Insurance System of Shanghai	Shanghai Center for Urban Environmental Meteorology		X	X		X	Good
Andrew et al. [23]	Assess the demand for emergency medical services during epidemic thunderstorm asthma	Time-series	Ambulance Victoria data warehouse and emergency service telecommunication	Australian Bureau of Meteorology				X		Good
Thien et al. [24]	Investigate the effect of thunderstorm asthma on health services and patient risk factors	Cross-sectional	Ambulance Victoria, the Victorian Department of Health and Human Services Victorian, Australian and New Zealand Intensive Care Society Adult Patient Database, census data	Australian Bureau of Meteorology

¹EDVs: emergency department visits for asthma. ²HAs: hospital admissions for asthma. ³Air pollution was considered a confounder in these studies.