RT Journal Article SR Electronic T1 Simplified calculations using likelihood ratios JF Evidence Based Medicine JO Evid Based Med FD BMJ Publishing Group Ltd SP 132 OP 132 DO 10.1136/ebm.11.5.132 VO 11 IS 5 A1 John G Sotos YR 2006 UL http://ebm.bmj.com/content/11/5/132.abstract AB