- M A Okun: Department of Psychology, Arizona State University, Tempe 85287-1104.
This meta-analysis demonstrated that interventions have a significant (p less than .05) immediate posttreatment influence on elders' subjective well-being but that their beneficial effect dissipates within 1 month. For 28 effect sizes derived from immediate posttreatment occasions (delay = 0 days), the median value was 0.67. Immediate posttreatment effect sizes for control enhancement (M = 1.12), psychoeducational (M = 0.70), and social activity (M = 0.66) treatments were significantly (p less than .05) above zero and not significantly different from each other. In contrast, for 17 effect sizes derived from delayed posttest occasions (delay greater than 0 days), the median value was 0.07. For effect sizes extracted from studies with both an immediate and a delayed posttest, the mean decrease over a 30-day period was 1.02.