ObjectiveTo develop a tool to assess current (past 30 days) and lifetime marijuana use in older Veterans.SettingUS Veteran's Affairs Healthcare System.Participants704 older Veterans were screened, 339 completed the initial survey, 100 completed the follow-up.Primary outcome measurePearson's correlation coefficient to assess strength of association between initial and follow-up survey on measures of current and lifetime marijuana use.ResultsBoth a 'gram-month' measure of marijuana smoked in the past 30 days (r=0.83) and a frequency-based measure assessing total number of times smoked in the past 30 days were reliable (r=0.89). Both a simple categorical measure of lifetime use (agreement=85%) and a continuous measure of lifetime use (r=0.82) were reliable.ConclusionsThe Cannabis Assessment Tool offers a reliable assessment of past 30 days and lifetime assessments of smoking cannabis in older adults
