RT Journal Article SR Electronic T1 Achieving health gain through clinical guidelines. I: Developing scientifically valid guidelines. JF Quality in Health Care JO Qual Health Care FD BMJ Publishing Group Ltd SP 243 OP 248 DO 10.1136/qshc.2.4.243 VO 2 IS 4 A1 J Grimshaw A1 I Russell YR 1993 UL http://qualitysafety.bmj.com/content/2/4/243.abstract AB