Salutogenic Healthy Aging Program Embracement (SHAPE) for Elderly-only Households

Aim and Hypothesis This study aims to develop and evaluate the effectiveness of a multi-dimensional, community-based health promotion and prevention program, SHAPE, on sense of coherence, self-efficacy, quality of life, health-promoting behaviours, and health-related outcomes among elderly residing in elderly-only households in Singapore.

It is hypothesized that compared with participants in the control group, participants in the experimental group will have improved sense of coherence, better quality of life, increase uptake of health-promoting behaviours, higher self-efficacy and other health outcomes.

Study Design A single-blinded two-arm, randomized controlled trial (RCT), pretest and repeated post-test design will be used. The study will be conducted in a small residential estate located in the west of Singapore. Stratified permuted block randomization will be used to allocate participants into experimental and control group. The 12-week SHAPE will be provided to elderly living in the blocks allocated to the experimental group, and both groups will receive usual activities offered in senior activity centre, community centre and voluntary welfare organisations. One research nurse (RN) together with a research assistant A (RA A) who has social work background will conduct the intervention, and another research assistant B (RA B) will conduct the data collection. The RA B will be blinded to participants' group assignment to prevent subjective bias stemming from the knowledge of grouping. Four measurements will be conducted at baseline prior to the intervention, at 3 months immediately after the intervention, 6 months, and 12 months from the baseline.

Sample Size Power analysis calculation on sample size is based on previous studies on community-based programs conducted in community-dwelling older adults which reported sense of coherence having a medium effect size (d=0.46-0.57). Sample size calculation is therefore calculated based on a medium effect size of 0.5. A minimum sample size of 64 participants in each group is needed to detect a difference between groups at an alpha of 0.05 and power of 0.80. We estimate 20% attrition rate, a total of 154 participants would be needed, with 77 in each group

Randomization To account for differences in living arrangement and ensure that elderly living in the same household are assigned to the same intervention or control group, stratified permuted block randomization will be used in this study. Participants will be grouped according to either of the three strata: (1) single elderly in a household, (2) two elderly from same household participating in the trial (a pair) and (3) only one out of two elderly from same household participating in the trial. Blocks of 10, with the assignment of 5 to experimental group and 5 to control group, will be used for each strata. Using a computerized randomization software, a statistician will generate the randomization list and prepare 3 different sets of sealed envelopes. According to their strata, the participant or the pair of participants will choose from the respective set of envelopes themselves to determine the group assignment.