id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-325565-cz9f65ca	Heederik, Dick J.J.	Go slow to go fast: A plea for sustained scientific rigor in air pollution research during the COVID-19 pandemic	2020-06-25		.txt	text/plain	2060	103	48	The second study used European data and, based on simple correlation analyses, associated long term (Jan-Feb 2020) exposure to nitrogen oxides (NOx) in the troposphere (resolution ~7*3.5km), assessed using satellite data, and absolute numbers of COVID-19-related deaths. [5] Positive associations were seen between levels of nitrogen dioxide and nitrogen oxide and increased COVID-19 mortality and reported number of cases, without adjustment for population size, age distribution or other confounding variables. In particular the two ecological studies which crudely correlate reported numbers of COVID-19 cases or mortality to regional air pollution levels ignored the time of introduction of COVID-19 in the different areas, did not take into account disease dynamics in any way, and ignored basic epidemiologic principles by using inadequate measures of disease frequency. The effect of air pollution on disease prognosis can be studied using more conventional approaches after COVID-19 infection.	./cache/cord-325565-cz9f65ca.txt	./txt/cord-325565-cz9f65ca.txt