4. General Discussion
depression
The current investigation had two goals: first, we sought to develop persuasive psychoeducational materials based on commonly held lay etiological models of depression and examine participants’ belief in CBT’s ability to disrupt mechanisms as described in such models (Study 1). Second, we aimed to examine the effects of providing tailored treatment descriptions on perceptions of CBT’s acceptability and credibility as a treatment for depression (Study 2). In Study 1, participants who received biology-oriented treatment descriptions rated the biological change mechanisms involved in CBT as more believable than those who received a generic cognitively oriented description. The Study 2 hypothesis that participants who received a tailored description would rate CBT more favourably than participants who received a generic description was not supported. Evidence points to increasing endorsement of biological models of depression among the general population [In endorsing the use of psychoeducational material which suggests that biological mechanisms may be disrupted through the effects of a treatment that is otherwise believed to operate through cognitive processes, we also acknowledge the instinctive skepticism surrounding biological bases of CBT. Indeed, not only are the roles of biological processes in treatment mechanisms consistent with the cognitive theory that CBT is built upon [The expanding literature, which now demonstrates the meaningful relationships between endorsing biological causes of depression and treatment preference, empowerment in seeking treatment, and prognostic pessimism, is highly suggestive [The findings from the current investigation also suggest that individuals already readily believe CBT is able to address relationship and stress mechanisms associated with depression, even in the context of classic cognitively oriented descriptions of the treatment. Importantly, we found that belief in the biological change mechanisms involved in CBT was relatively low across groups. With that, and consistent with Lebowitz et al.’s [The believability of the relationship mechanisms of CBT was also predicted by the description allocation beyond demographic variables. Interestingly, those who received a relationship-focused description of CBT specifically did not report higher degrees of believability of the relationship mechanism of treatment. Instead, those who received a complex biological description were less convinced of the proposed relationship mechanisms of CBT than those who received a generic CBT description. This pattern of results is consistent with findings from previous studies demonstrating that participants tend to select psychological interventions (including CBT) as their preferred treatment for depression when endorsing more psychology-oriented causal models [Taken together, a consistent pattern of results emerged across the studies (current Study 1 included): (a) people are more reluctant to believe that CBT and/or other psychological interventions operate through biological mechanisms, and promisingly, (b) explicit psychoeducation about why or how CBT (or other interventions) can disrupt biological mechanisms in depression appears effective in improving the believability of the treatment. In Study 2, we found no significant difference in perceptions of acceptability, credibility or expectancy between participants receiving a treatment description tailored to match baseline etiological beliefs about depression and those receiving a generic cognitively oriented description. This finding is inconsistent with the results of past work that demonstrated the superiority of tailored health messages over generic ones in promoting a health behaviour change [Considering the results of our studies together, tailoring treatment descriptions (to be specifically biologically oriented) appears to improve the believability of the treatment mechanisms but does not improve acceptability and credibility/expectancy beliefs. Although buy-in to the mechanisms of a treatment is likely to have an impact on perceptions of credibility and/or acceptability, beliefs regarding the mechanisms of a treatment are separate from perceptions of its acceptability and credibility. As Khalsa [Our investigation adds to the existing literature in several ways. First, we examined complex and simple versions of the descriptions in Study 1. To our knowledge, this is the only study on beliefs about CBT and depression to compare the effects of relatively superficial descriptions to more elaborate ones. Second, the results of Study 1 also demonstrate that people readily believe in the relationship- and stress-oriented change mechanisms brought about by CBT, even in the context of a generic, classic description of the CBT model; however, generic descriptions of CBT that rely on classic cognitive behavioural mediational hypotheses do little to improve the believability of CBT’s ability to alter biological mechanisms once such mechanisms are invoked or suggested. Finally, to our knowledge, no study has examined the effect of tailoring brief psychoeducational materials on perceptions of the acceptability and credibility of CBT as a treatment for depression. The findings from this investigation must be considered in light of its limitations, which pave the way for future research. First, we did not measure the participants’ baseline perceptions of CBT and depression beliefs in Study 1 or baseline treatment perceptions of acceptability or credibility/expectancy in Study 2. As such, we could not ascertain any pre–post changes in beliefs or treatment perceptions of acceptability and credibility/expectancy. Second, in Study 2, the participants were offered a list of only four choices of potential explanatory models at baseline and did not have the choice to endorse multivariate models (e.g., biopsychosocial explanations) as causes for depression. It is possible that a sizable proportion of our sample may have endorsed a multivariate model if provided the option. Third, we relied on crowd-sourced samples. Although such samples confer several advantages (e.g., access to more diverse demographic characteristics and relatively larger samples), criticisms about non-naïveté among participants and the representativeness of the samples remain [In light of these limitations, the findings offer directions for further research. Future research may seek to investigate the effect of tailoring psychoeducational materials on multiple dimensions simultaneously. These dimensions may be based on an assessment of prior experience with CBT and/or other psychotherapies, individual differences (e.g., psychological mindedness and self-efficacy), perceived barriers to CBT (e.g., stigma and misconceptions), and demographic characteristics (e.g., educational attainment), to name a few. Additionally, considering the popularity of biological models of depression in the general population, ways of improving the current biology-oriented descriptions or the efficacy of alternate psychoeducational interventions may be explored. It may also be worth using longitudinal designs to examine whether effects on beliefs persist at follow-up assessments and whether they materialise into behavioural change when seeking treatment. Lastly, distributional channels may be compared through ecologically valid and/or naturalistic formats such as websites [