Choi · Proceedings of the National Academy of Sciences of the United States of America 2025 · systematic review and meta-analysis · n=24,804 participants across 145 papers (163 samples)

A meta-analysis of the effectiveness of gratitude interventions on well-being across cultures.

Cited 11 times in the scientific literature.

Level 1 - systematic review of randomized trials

Meta-analysis of intervention trials (including randomized controlled trials)

PubMed 40627390 · doi:10.1073/pnas.2425193122 · record verified 2026-08-31

What was done

Authors conducted a preregistered meta-analysis evaluating the effectiveness of gratitude interventions on well-being across cultures. The analysis synthesized data from 145 papers, 163 samples, 727 effect sizes, and 24,804 participants across 28 countries. They tested for overall effect size, cultural moderation, and methodological moderators (well-being outcome type, intervention type, and randomization), while assessing publication bias and influential cases.

What was found

Gratitude interventions produced a small overall increase in well-being, Hedges' g = 0.19, 95% CI [0.15, 0.22]. Significant between-country differences were found, but no tested moderators explained this cross-cultural variability. Methodological moderation indicated larger effect sizes when well-being was measured as positive affect, when multiple intervention types were combined, and when studies were randomized controlled trials. Results were robust against publication bias and influential cases.

Why it matters

This review establishes a small but statistically significant global benefit of gratitude interventions on well-being, while identifying significant cross-country variation that highlights the need for better-targeted cross-cultural research.

Limits

Tested moderators failed to explain the observed cross-country variability. The abstract does not provide details on intervention duration, long-term persistence of effects, comparator/control conditions, or specific clinical versus non-clinical sample characteristics.

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