Web-based self-help with and without chat counseling to reduce cocaine use in cocaine misusers: Results of a three-arm randomized controlled trial.

•Chat counseling in addition to web-based self-help in cocaine misusers from the general population was investigated in a RCT.•Many cocaine misusers were reached and reduced their use with a CBT-based online program with or without chat counseling.•Due to dropouts and serious difficulties reaching subjects for follow-ups, differences between study arms are inconclusive.