The Robust Benefits of Positive Psychology Interventions

Bruce Daisley (September 27, 2022) published “Why Quick-Fix Resilience Doesn’t Work” here at PsychologyToday.com. His claim: “peer-reviewed studies show quick-fix resilience courses don’t work.” During his writing a book on resilience, he writes, “I was struck by the number of times people told me that the resilience course they were sent to didn’t work.” To bolster his impression, he claims he reviewed the relevant published data, leaning heavily on Jesse Singal’s (2021) The Quick Fix.

Neither Singal nor Daisley came close to completely “reviewing the published data” on resilience training, much of which, as they note, is based on my work. Instead, they cite only a couple of old, small studies, which were ambiguous. But they failed altogether to review the four recent, much larger meta-analyses of positive psychology interventions and resilience training. Or perhaps they did but chose not to tell readers about them.

Let’s examine the evidence:

Effectiveness of Positive Psychology Interventions (PPIs)

Daisley and Singal tell their readers only about a scattering of negative evidence. They fail to share the scores of controlled studies showing that PPIs work. Thankfully there is a method, meta-analysis, for evaluating all existing studies together.

In 2020, The Journal of Positive Psychology published the most comprehensive meta-analysis of PPIs. Carr et al (2020) reviewed 347 studies involving over 72,000 participants from clinical and non-clinical populations in 41 countries. The effect sizes of PPIs with an average of 10 sessions over six weeks offered in multiple formats and contexts was evaluated. At post-test, PPIs had significant “small” to “medium” effects on well-being (g = 0.39), strengths (g = 0.46), Quality of Life (g = 0.48), depression (g = −0.39), anxiety (g = −0.62), and stress (g = −0.58). Gains were maintained at three months follow-up.

The lay reader may not be familiar with the terms “small,” “medium,” and “large” to describe effect sizes. An effect size is the mean difference between two populations divided by the standard deviation of the whole population. Effects in therapy are usually “small” or “medium”: Researchers celebrate when “medium” occurs, and “large” effects of medications or psychotherapy are very rare. Effect sizes in prevention, such as these studies, are “small” (very rarely “medium”) or more usually non-existent. So, a “small” effect size in the prevention of psychological problems is not a pejorative. It is a good result; the best that can be anticipated.

In addition to this unmentioned 2020 meta-analysis, Daisley and Singal fail to tell readers about three complete, recent meta-analyses showing that resilience programs work:

Ma, Zhang, Huang, & Cui (2020) published a comprehensive meta-analysis, in the Journal of Affective Disorders. They found these programs to be effective, reviewing 38 controlled studies, including 24,135 individuals. At post-intervention, the mean effect size was significant and subgroup analyses revealed significant effect sizes for programs administered to both universal and targeted samples, programs both with and without homework, and programs led by teachers. The mean effect size was maintained at 6 months follow-up, and subgroup analyses indicated significant effect sizes for programs administered to targeted samples, programs based on the Penn Resiliency Program, programs with homework, and programs led by professional interventionists.

Similarly, Ahlen, Lenhard, & Ghaderi’s (2015) meta-analysis in The Journal of Primary Prevention reported 30 randomized studies meeting their strong inclusion criteria, namely peer-reviewed, randomized, or cluster-randomized trials of universal interventions for anxiety and depressive symptoms in school-aged children. There were “small,” but significant, effects for anxiety and depressive symptoms as measured at immediate posttest. At follow-up, which ranged from 3 to 48 months, effects were significantly larger than zero for depressive but not anxiety symptoms.

Dray, Bowman, et al’s (2017) meta-analysis in The Journal of the American Academy of Child and Adolescent Psychiatry reviewed 49 studies. For all trials, resilience-focused interventions were effective relative to a control in reducing depressive symptoms, internalizing problems, externalizing problems, and general psychological distress. For child trials (meta-analyses for 6 outcomes), interventions were effective for anxiety symptoms and general psychological distress. For adolescent trials (meta-analyses for 5 outcomes), interventions were effective for internalizing problems.

Daisley and Singal also fail to mention Seligman, Allen, Vie et al (2019), a recent predictive study of more than 70,000 soldiers deployed to Iraq and Afghanistan between 2009 and 2013. It is highly relevant to resilience programs. We attempted to predict from pre-existing psychological variables who would come down with PTSD after deployment and combat to Iraq or Afghanistan. This is the complete cohort, not a mere sample. About 5% developed diagnosed PTSD. Soldiers who were worst on catastrophic thinking were 29% more likely to develop PTSD than soldiers with average catastrophic thinking, whereas soldiers lowest on catastrophic thinking were 25% less likely to develop PTSD. Soldiers high in catastrophic thinking and experiencing high combat intensity were 274% more likely to develop PTSD than those low on both. This suggests a major way to prevent PTSD: Keep catastrophizers away from intense combat. Reducing catastrophization is an explicit target of PPIs — and this study showed that reducing it likely would prevent PTSD.

Positive Psychology Essential Reads

The Untold Truth About the Origins of Positive Psychology

Enhancing the Well-Being of Groups Is Hard

Another huge, relevant study — Lester, Stewart, Vie, et al, (2021) — tried to predict heroism and exemplary job performance over the course of four years. The researchers measured high positive affect (PA), low negative affect (NA), and high optimism at the outset. Each of these variables predicted awards for performance and awards for heroism in a sample of 908,096 soldiers, in which 114,443 soldiers (12.6%) received an award. These variables predicted almost fourfold greater awards. This showed that three of the resilience variables that PPIs target are major modifiable predictive factors for exemplary army job performance and for battlefield heroism.

Daisley’s and Singal’s claim that “resilience programs don’t work” is false. Positive Psychology interventions are highly effective. PPIs preventing anxiety and depression, as well as resilience programs, are supported by lots of scientific evidence. This evidence reliably shows reductions in depression, anxiety, and stress and reliable increases in well-being in adults and children. These findings emerge from many studies, in many settings including the military, and with extremely large samples. In sum, the evidence supporting the benefits of resilience programs and positive psychology interventions, is massive, it is scientifically state-of-the-art, and it has been replicated frequently.