Six trials were included in the review (1,499 participants, range 80 to 525). Three trials provided follow-up data at two weeks, four weeks or six months; other trials measured outcomes at post-test only. Study quality scores ranged from 5 to 9. One study scored 9, three scored 6 and two scored 5. Two of the included trials involved members of the review team.
All six trials found interventions to be significantly better than controls at post-test on at least one help-seeking measure. All five trials that measured attitudes, willingness or beliefs found a significant improvement in help-seeking attitudes at post-test of an intervention compared to control. Effect sizes ranged from 0.12 to 0.53. One of three trials that measured behaviour found a significant difference between intervention and control for help-seeking behaviour at post-test (d=0.24). The only study to measure help-seeking intentions at post-test found no significant difference between treatments. Two of the three studies that provided follow-up data found a significant improvement in help-seeking attitudes (at two or four weeks) and one did not (at six months).
Interventions with mental health literacy content were effective at improving help-seeking attitudes in five out of six studies but had no effect on help-seeking behaviour in any of the three studies that assessed this outcome. Evidence was more sparse for other types of intervention.