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. Author manuscript; available in PMC: 2012 Feb 13.
Published in final edited form as: J Clin Epidemiol. 2008 Jul 10;61(11):1132–1143. doi: 10.1016/j.jclinepi.2007.12.009
YES....................................................1
NO.....................................................5 GO TO *FD18
DON’T KNOW.................................8 GO TO *FD18
REFUSED..........................................9 GO TO *FD18