| Literature DB >> 5543533 |
Abstract
Keywords: Control Groups; Diseases; Follow-up Studies; Incidence; Research Methodology; Retrospective Studies; Studies
Year: 1971 PMID: 5543533 DOI: 10.1093/oxfordjournals.aje.a121235
Source DB: PubMed Journal: Am J Epidemiol ISSN: 0002-9262 Impact factor: 4.897