 Sample size calculation was based on power analysis. Power analysis adopts a hypothesis-testing method to determine sample size according to several parameters which include pre-specified significance level, desired power level and expected effect size. Assuming a two-tailed alpha of 0.05, a probability of 0.2 for beta error 80 power, and an effect size of 0.28 after calculating with respect to the same primary outcome measure self-efficacy from results of two previous researches which provide home visit and telephone follow up to older adults, 200 subjects per group are required. With reference to the 10 to 15 attrition reported in previous community-dwelling elderly program, assume there is a 20 drop out rate in this study, the total sample size needed is 240 subjects per group i.e. a total of 480 subjects. 