S J Evans. Show Affiliations »
Abstract
Mesh: See more » Epidemiologic MethodsHumansRandom AllocationSampling StudiesSelection Bias
Year: 1991 PMID: 2001503 PMCID: PMC1669002 DOI: 10.1136/bmj.302.6772.302
Source DB: PubMed Journal: BMJ ISSN: 0959-8138