Abstract
Background: This study aimed to review and synthesize evidence related to the effectiveness of internet-based cognitive behavioral therapy (iCBT) for reducing depressive symptoms in older adults.Method: The authors conducted a systematic review of intervention studies testing iCBT for symptoms of depression in older adults. An initial search of PubMed, PsychINFO, and Web of Science was undertaken, followed by a manual search of reference lists of the relevant articles. The Cochrane Risk of Bias Tool was used to appraise study quality. The mean effect size for included studies was estimated in a random effects model. Meta-regression was used to examine potential moderators of effect sizes.Results: Nine studies met the inclusion criteria, including 1272 participants averaging 66 years of age. The study design included randomized controlled trials (k = 3), controlled trials without randomization (k = 2), uncontrolled trials (k = 2), and naturalistic evaluation (k = 2). Seven studies tested iCBT with some level of therapist involvement and 2 examined self-guided iCBT. Six studies tested interventions specifically adapted for older adults. The mean within-group effect size was 1.27 (95% CI = 1.09, 1.45) and the mean between-group effect size was 1.18 (95% CI = 0.63, 1.73). Participants' age was negatively associated with within-group effect sizes (b = -0.06, p = .016).Conclusions: iCBT is a promising approach for reducing depressive symptoms among older adults with mild to moderate depressive symptoms. However, studies involving older adults in iCBT trials were limited, had considerable heterogeneity, and were of low quality, calling for more studies with rigorous designs to produce a best-practice guideline.