J I Mann, M P Vessey. Show Affiliations »
Abstract
Mesh: See more » Epidemiologic MethodsHumansResearch DesignRetrospective Studies
Year: 1979 PMID: 526828 PMCID: PMC1597192 DOI: 10.1136/bmj.2.6203.1507-a
Source DB: PubMed Journal: Br Med J ISSN: 0007-1447