A screening questionnaire was posted to 27,000 individuals aged 18 to 52 randomly selected from the Canberra electoral roll. 6130 people (22.7% response rate; 24.6% excluding those returned to sender) returned the screening questionnaire and 657 respondents met inclusion criteria. The screening questionnaire included a brief questionnaire (about two printed pages) assessing basic demographic information, education level, depression symptoms, help-seeking and internet use. Respondents were not eligible for inclusion in the trial if they; (i) scored below 12 on the Kessler Psychological Distress Scale (K10)10, (ii) indicated they did not have Internet access at home or at work, (iii) indicated they did not wish to participate in an intervention, or (iv) were under psychiatric or psychological care. Of those who responded, 525 participants met these criteria, returned a letter of consent, and were randomised to the interventions. 414 participants provided post intervention depression scores and these individuals formed the sample analyzed here. The sample comprised 114 men and 300 women. The mean respondent age was 36.8 years (SD = 9.3), and the mean Kessler score was 17.5 (SD = 5.0) at screening.

The present study used data from a recently completed randomised controlled trial of two Internet sites 911. One of these Internet sites, BluePages 12, delivers information about a range of psychological, medical and alternative treatments and recommends those supported by scientific evidence. At the time of the trial, the BluePages website reviewed 5 medical, 7 psychological and 36 alternative treatments, recommending 3, 5 and 13 of these, respectively. The recommended therapies were based on systematic reviews of treatments 813. The second site, MoodGYM, provides online cognitive behaviour therapy (CBT). The site consists of five modules that provide cognitive behaviour therapy, strategies to manage emotional distress, relaxation and problem solving. The site provides downloadable summary pages at the end of each module, which provide individualized symptom scores and homework completion outcomes. The site offers a user profile which tracks changes in anxiety, depression and dysfunctional thinking across modules. A control condition involved telephone contact with an interviewer but no access to the websites. Participants were randomly assigned to receive either; a) BluePages (n = 165, at endpoint n = 136), b) MoodGYM (n = 182; at endpoint n = 121) or c) a control condition (n = 178, at endpoint n = 157) in which an interviewer asked open-ended questions about factors that may influence depression. Participants were randomised to interventions using the SPSS SELECT CASES random selection option. A flow chart of participation in the trial is included in a previous publication 9.

Participants completed questionnaires delivered through the mail at screening, pre-test, endpoint and at six months after the trial. Those in the BluePages and MoodGYM conditions were provided with a login identification number and a manual containing information about MoodGYM or BluePages. This manual outlined which sections or modules of the sites participants were to complete for each of 5 weeks. Interviewers maintained weekly telephone contact with participants in all conditions over the period of the intervention (a total of 6 contacts of approximately 10 minutes each).

Interviewers were provided with separate instruction booklets for each participant containing verbatim instructions for each of the weekly contacts. Participants randomised to the control intervention were phoned weekly for 10 minutes to discuss lifestyle and environmental factors that may influence depression. A different topic was discussed each week; 1) physical and artistic activities, 2) education and hobbies, 3) social financial and family roles, 4) work habits and stress, 5) physical health, medication and pain, and 6) nutrition and alcohol. At the end of the intervention period and at six months all participants were sent a questionnaire. The study was approved by the Human Ethics Committee of the Australian National University. Participants provided written informed consent.

The first set of analyses addressed the question of whether the interventions were associated with reports of help seeking. It consisted of a series of separate logistic regressions assessing the impact of BluePages compared to the control condition, and BluePages compared to the MoodGYM site on help seeking for each of the specific treatments used (e.g., antidepressant medication). A second analysis assessed the effect of these the two interventions and the control condition on help seeking from different sources of help (professionals/family). A further set of four linear regressions examined whether those in the BluePages intervention compared to the two other interventions used different categories of treatments.

BluePages was selected as the comparison condition in preference to the control condition because we hypothesized it would lead to greater help seeking for evidence-based treatments than the other two conditions. Supplementary analyses addressed the question of whether the reported seeking of help from a specific treatment or source was associated with a reduction in depressive symptoms. Separate linear regressions were used to examine the reported use of each specific treatment and its association with depression (CES-D scores) at post intervention and at six months. A further four linear regressions examined whether the category types of treatment predicted depression. A second set of supplementary analyses investigated the relationship between the severity of depression and the reported uptake of specific treatments or sources, controlling for intervention type. A series of separate logistic regressions were used to assess the effect of the severity of depression (CES-D scores) at pre-intervention on the use of each treatment. Four linear regressions were used to examine the impact of depression on the number of every day, complementary, dietary and professional treatments used. No formal adjustment was undertaken for the number of comparisons that were tested. However, the majority of effects reported would remain significant even if correct using a extremely conservative approach such as the Bonferroni method. Nevertheless, the possibility of inflated Type I error arising from evaluating multiple treatments should be borne in mind.

There were no significant differences in age, sex and CES-D score between the intervention conditions at baseline 911. Participants who completed the post-intervention questionnaire did not differ in age, sex or years of education or the CES-D at endpoint in comparison to those who did not return the questionnaire, although the dropouts had higher depression scores at baseline (F (1,523) = 5.15, p = 0.24).

Both BluePages and MoodGYM significantly reduced depression symptoms at post intervention relative to the control condition. Scores reduced 4.5 points (1.8 to 7.3) (95% confidence interval) for MoodGYM and 3.6 points (1.0 to 6.3) for BluePages relative to the control condition.

Frequencies for the reported use of each treatment are shown in Table 1. The results for the logistic and linear regressions are also displayed. Compared to BluePages, MoodGYM participants were more likely to report using cognitive behavioural therapy, exercise and massage. Both MoodGYM and control participants were more likely to report listening to music than were BluePages participants. Compared to BluePages, the control group was more likely to report seeking the help of family and friends. Both MoodGYM and the control condition were associated with the reported use of more everyday treatments. MoodGYM was also associated with the seeking of more complementary and professional treatments. These analyses were repeated as six months (Table 2). A number of the differences between the intervention groups were no longer significant. However, MoodGYM participants were still more likely to say they had used cognitive-behavioural therapy than those in BluePages (OR = 2.73; p = 0.011), and to use everyday treatments (B = .48, p = .044). After six months those in the control group were still more likely to have listened to music than those in the BluePages intervention (OR = 2.10, p = .005), and were now more likely to report the use of pets as a form of treatment than those in BluePages (OR = 1.86, p = .018). Both MoodGYM participants and the control group were more likely to use alcohol as a form of treatment at six months, than those in BluePages (OR = 2.26, p = .031, OR = 2.13, p = .037).

Table 3 shows the mean depression scores at post intervention for the users and non-users of each individual treatment. These analyses include individuals from the three intervention conditions combined. Table 3 also lists the results of the linear regressions used to assess the effect of the reported use of each specific treatment, sources of help and treatment categories on depression. Intervention condition and depression at pre-test were controlled for in these analyses. Users of relaxation and those reporting "doing things that they enjoyed' were less depressed. Use of alcohol and the number of professional treatments used were associated with higher levels of depression. These analyses were repeated at six months. There were no major differences in findings at 6 months compared to immediately post-intervention for most of the relationships (Table 4). However, the number of professional treatments used, doing enjoyable things and drinking alcohol, were not longer significant predictors of CES-D scores after six months. Relaxation therapy continued to be associated with lower CES-D scores (B = -.378, p = 0.015). New associations after six months were that CBT was now significantly associated with higher CES-D scores (B = 3.61, p = 0.015), seeing a GP was significantly associated with lower CES-D scores (B = -.2.77, p = .026), and being with pets was associated with lower CES-D scores (B = -3.19, p = .002).