OBJECTIVE: To investigate whether immediate effects of a 3-year educational intervention in primary health care were confirmed 18 months after the end of the intervention. STUDY DESIGN AND SETTING: A controlled 3-year intervention study in 34 Danish municipalities with randomization and intervention at municipality level. The 17 intervention municipality visitors received regular education, and GPs were introduced to a short assessment program. The effect was measured at the individual level by questions about functional ability at the end of the intervention period and 1(1/2) years later; 4,060 older adults living in the municipalities participated. We adopt the approach introduced by Dufouil et al. (2004) and treat dropouts due to death differently from dropouts from other reasons. RESULTS: Educational intervention to primary care professionals was associated with better functional ability in surviving women at the end of the intervention (odds ratio [OR]: 1.24, 95% confidence interval [CI]=1.07-1.45), from the end of the intervention until 1(1/2) years later (OR: 1.21, 95% CI=1.03-1.44) and during the total study period (OR: 1.22, 95% CI=1.06-1.42). No effects were seen in men. CONCLUSION: The effect of a brief, feasible educational intervention for primary care professionals is sustained in women 1(1/2) years after the end of the intervention.