RT Journal Article SR Electronic T1 Validation of self reported smoking JF Journal of Epidemiology and Community Health JO J Epidemiol Community Health FD BMJ Publishing Group Ltd SP 163 OP 164 DO 10.1136/jech.56.3.163 VO 56 IS 3 A1 M Rebagliato YR 2002 UL http://jech.bmj.com/content/56/3/163.abstract AB