RT Journal Article SR Electronic T1 Viral infections need to be excluded from the cohort for the results to be truly meaningful JF Evidence Based Medicine JO Evid Based Med FD BMJ Publishing Group Ltd SP 93 OP 93 DO 10.1136/ebm.12.3.93 VO 12 IS 3 A1 Qureshi, Kashif M A1 Robbie, Scott A1 Kashani, Shahram YR 2007 UL http://ebm.bmj.com/content/12/3/93.abstract AB