id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-030772-swha1e4m	Huizinga, Tom W J	Interpreting big-data analysis of retrospective observational data	2020-08-21		.txt	text/plain	986	47	53	1 In The Lancet Rheumatology, Jennifer Lane and col leagues present a study using claims data and elec tronic medical records (mostly of patients with rheuma toid arthritis) to analyse the longterm risks of cardiovas cular complications (among other outcomes) in about 1 000 000 users of hydroxychloroquine compared with more than 300 000 users of sulfasalazine. It has been convincingly shown that most published data are false, 4 and the corollary that the hotter a scientific field (with more scientific teams involved), the less likely the research findings are to be true is a relevant consideration given the recent discussions around use of hydroxychloroquine in patients with COVID19. It is important to note that the authors used stateoftheart methods to deal with the chal lenges of studying retrospective electronic medical record data; they did a newuser cohort study and a selfcontrolled case series to avoid the risk of bias in a casecontrol design, using propensity scores, fitting models with ten-fold cross validation, and negative control outcome analyses.	./cache/cord-030772-swha1e4m.txt	./txt/cord-030772-swha1e4m.txt