(PS5-A13) The Efficacy of Four Self-guided CBT Modules on Depression and Anxiety Symptoms

Even among majority populations in high-income countries, less than half of those experiencing anxiety or depression receive treatment meeting their subjective needs (Mojtabai, 2009). One method of improving access to psychological services is through increasing the availability of low-intensity, brief interventions. To this end, some initiatives, such as Improving Access to Psychological Therapies (IAPT), have assimilated stepped care approaches into their models (Clark, 2011). In stepped care, treatment is provided sequentially with lower intensity interventions, such as computerized CBT and guided self-help, representing the first stage of care with more intensive treatment options at later steps if previous steps don’t result in sufficient improvement. This increases access to services as lower intensity treatments require less therapist time and/or may be performed by interventionists with less intensive training. This is particularly true for self-guided interventions which require minimal to no therapist contact. Additionally, the literature is generally supportive of brief, self-guided interventions. Several meta-analyses have demonstrated that, on average, compared to care-as-usual or waitlist conditions, self-guided interventions significantly reduce symptoms of depression, however, with relatively small effects (Andersson & Cuijpers, 2009; Cuijpers et al., 2011b; Karyotaki et al., 2017). In the current study, we examined the efficacy of four self-guided, CBT skills modules (i.e., cognitive, behavioral, interpersonal, mindfulness) on depression and anxiety symptoms.

Participants (n = 224) were randomized to either a cognitive (n = 61), behavioral (n = 62), interpersonal (n = 47), or mindfulness (n = 54) module. Participation took place over the course of 3 weeks. Each module consisted of three 5-minute educational videos (one per week) on coping skills within the domain of their assigned module. Participants also watched a series of brief review videos to promote comprehension. In addition, participants were expected to practice concepts from the videos by completing 9 module-specific worksheets over the course of the 3 weeks. Assessments of depression (QIDS-SR; Rush et al., 2003) and anxiety (GAD-7; Spitzer et al., 2006) symptoms were completed weekly.

Repeated measures linear regression models were conducted for both depression and anxiety symptoms. In each model, outcome measures were regressed on time (in weeks), while allowing for random intercepts. The results suggested a significant decrease in both depressive, B = -0.75, t(541.57) = -8.94, p < .001, and anxiety, B = -0.63, t(536.19) = -6.25, p < .001, symptoms over time. To determine whether the modules were statistically equivalent in efficacy to one another, two one-sided tests (TOST) of equivalence were performed. Modules tended to be equivalent in reducing symptoms of depression. However, modules did not tend to be equally effective in reducing symptoms of anxiety.