Those confounded vitamins: what can we learn from the differences between observational versus randomised trial
Debbie A Lawlor1, George Davey Smith, Devi Kundu
1Department of Social Medicine, University of Bristol, UK. d.a.lawlor@bristol.ac.uk
Lancet (London, England)
|May 26, 2004
Summary
No abstract available in PubMed .
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