drug group relative to placebo. Reasons for early termination were coded at time of termination under double-blind conditions and served as the basis for the following assumptions: 4 subjects who were verified as abstinent for their entire study participation and as terminating for work-related reasons were classified as responders; one additional drop-out provided drinking data that conflicted with data from their collateral informant and non-response was assumed, which was later corroborated by the subject. Sixty of 65 drop-outs were known to have used alcohol prior to dropping and were known to be non-responders.
