Related Experiment Video
Updated: Feb 10, 2026

Collecting Saliva and Measuring Salivary Cortisol and Alpha-amylase in Frail Community Residing Older Adults via Family Caregivers
Published on: December 18, 2013
Effects of Horticulture on Frail and Prefrail Nursing Home Residents: A Randomized Controlled Trial
Claudia K Y Lai1, Rick Y C Kwan1, Shirley K L Lo1
1School of Nursing, The Hong Kong Polytechnic University, Hong Kong, SAR, China.
Objective:
Frail nursing home residents face multiple health challenges as a result of their frail status. The aim of this study was to examine the effects of HT on the psychosocial well-being of frail and prefrail nursing home residents.
Design:
Randomized controlled trial.
Setting:
Nursing homes.
Participants:
One hundred eleven participants were randomly allocated into the intervention [horticultural therapy (HT)] and control (social activities) conditions.
Intervention:
HT group participants attended a weekly 60-minute session for 8 consecutive weeks. Control group activities were social in nature, without any horticulture components.
Measurements:
The outcome measures include happiness, depressive symptoms, self-efficacy, well-being, social network, and social engagement. The time points of measurement were at baseline (T0), immediately postintervention (T1), and 12 weeks postintervention (T2). A modified intention-to-treat approach was adopted. A multivariate general estimating equation was used to analyze the data.
Results:
Forty-six and 50 participants received at least 1 session of the intervention and control condition protocol, respectively. A significant interaction effect between group and time was observed only on the happiness scale (β = 1.457, P = .036), but not on other outcome variables. In a follow-up cluster analysis of those who received HT, a greater effect on subjective happiness (mean difference = 6.23, P < .001) was observed for participants who were happier at baseline.
Conclusion:
HT was found to be effective in promoting subjective happiness for frail and prefrail nursing home residents. Its favorable effect suggests that HT should be used to promote the psychosocial well-being of those who are frail.
Related Concept Videos
Trial and Error and Algorithm
Clinical Trials: Overview
Clinical Trials
There are four phases in a clinical trial. A phase one...
Random Error
Random Variables
Uppercase letters such as X or Y denote a random variable. Lowercase letters like x or y denote the value of a random variable. If X is a random variable, then X is written in words, and x is given as a number.
For example, let X = the...
Randomized Experiments
Simple randomization
Simple...

