Effect of a community-based nutrition intervention incorporating social cognitive theory constructs and transtheoretical model-based counseling among communitydwelling elderly in Korea: a quasi-experimental study

OBJECTIVES: This study evaluated the effects of a 7-week nutrition intervention based on the personal and environmental constructs of social cognitive theory (SCT) and the transtheoretical model (TTM) on dietary behavior-related factors, dietary behavior outcomes, and stages of dietary behavior change among community-dwelling older adults. METHODS: A quasi-experimental nonequivalent control group pretest-posttest design was conducted from May to December 2024 at seven senior facilities in Seoul and Gyeonggi, Korea. Older adults aged ≥ 65 years were assigned by facility to either an intervention group (n = 66; four facilities) or a control group (n = 65; three facilities). The intervention group completed a 7-week program consisting of baseline assessment, five weekly group education sessions, individualized nutrition counseling, and post-intervention assessment. The control group received one general nutrition education session. Outcomes included dietary knowledge, outcome expectations, value expectations, self-efficacy, environmental factors (food accessibility and household food availability and social support), dietary behavior outcomes assessed using the Nutrition Quotient for the Elderly (NQ-E), and stage of change. Program effects were analyzed using ANCOVA adjusted for age, family composition, education, baseline dietary knowledge, and value expectations. RESULTS: Compared with the control group, the intervention group demonstrated significantly greater improvements in dietary knowledge (P < 0.001), outcome expectations (P = 0.018), self-efficacy (P < 0.001), environmental factors (P < 0.001), and NQ-E total score (P = 0.011). No significant between-group difference was observed for value expectations. The proportion of participants in the action stage increased from 9.1% to 93.9% in the intervention group, and post-intervention stage distribution differed significantly between groups (P < 0.001). Program satisfaction was high (4.69 ± 0.41). CONCLUSION: A 7-week nutrition intervention incorporating SCT-based personal and environmental constructs and TTM-based stage-matched counseling improved dietary behavior-related factors, dietary behavior outcomes, and stage distribution among community-dwelling older adults.