Researchers conducted a meta-analysis of randomized controlled trials to evaluate the efficacy of positive psychotherapy (PPT) in reducing negative psychological outcomes and improving positive ones. The findings from the study, led by Thole Hilko Hoppen, MD, suggested that PPT was effective, at least in the short-term, although authors called for higher-quality trials to affirm the results.
Randomized controlled trials, as well as related systematic reviews and meta-analyses, published since the inception of PPT in 2006 through February 2020 were pulled from the Medline, PsycINFO, and Web of Science databases. Researchers ultimately included 20 randomized controlled trials with a total of 1,360 participants. Their findings were published in BMJ Open.
Compared with waitlist control conditions at post-treatment assessment, PPT produced moderate effect sizes for increasing positive outcomes (g = -0.72, 95% CI -1.31 to -0.14, k = 10, numbers needed to treat (NNT) = 2.55) and reducing negative outcomes (g = 0.48, 95% CI 0.18-0.78, k = 8, NNT = 3.76). Compared with active control conditions at post-treatment assessment, PPT yielded large effect sizes for increasing positive outcomes (g = -0.92, 95% CI -1.74 to -0.11, k = 6, NNT = 2.05) and reducing depression (g = 0.94, 95% CI 0.18-1.70, k = 6, NNT = 2.03). Researchers found no significant differences in efficacy between PPT and other established treatments, such as cognitive behavioral therapy.
The study noted that analysis was widely limited by the scarcity of available trials. Additionally, long-term efficacy could not be determined due to lack of data from follow-up assessments.
According to the authors, the study ultimately supported that PPT can increase positive outcomes and decrease negative outcomes in the short-term. However, they asserted that more trials that include follow-up assessments are needed to evaluate the long-term effectiveness of PPT.
Source: BMJ Open