Free range users and one hit wonders: community users of an Internet-based cognitive behaviour therapy program

Little is known about the predictors of symptom change or the methods that might increase user 'compliance' on websites designed to improve mental health outcomes. The present paper: (i) examines predictors of expected final depression and anxiety scores on the MoodGYM website as a function of user characteristics; and (ii) compares the compliance rates of the original site with the new public version of the site (MoodGYM Mark II). The latter site requires compulsory completion of 'core' online assessments and may increase completion of site questionnaires.

MoodGYM Mark I participants were 19,607 visitors (public registrants) between April 2001 and September 2003 plus 182 participants who had been randomly assigned to MoodGYM in an earlier trial (The BlueMood Trial). MoodGYM Mark II participants were 38,791 public registrants of the MoodGYM Mark II site collected between September 2003 and October 2004. Symptom assessments are repeated within the website intervention to allow the examination of change in symptoms. Outcome variables were gender, initial depression severity scores, number of assessments completed and final anxiety and depression scores.

Men are predicted to be 0.19 units (SE=0.095) higher than women on depression, controlling for the initial depression level and number of modules completed. For initial depression scores above 2, it is predicted that the final score will indicate improvement relative to the initial score, the magnitude of the improvement increasing as a function of the number of modules attempted. For initial anxiety scores above 2, it is predicted that the final score will indicate improvement relative to the initial score, the magnitude of the improvement increasing as a function of the number of modules attempted. Mark II registrants were more likely than to Mark I registrants to complete onsite assessments.

Visitors to the MoodGYM site are likely to have better psychological outcomes if they complete more of the site material. Compulsory completion of core sections increases assessment completion. There is a need to examine further the significance of attrition from online interventions, to develop methods of handling missing data, and to investigate strategies to improve visitor dropout.