Author: Ng, Wing Man
Title: A feasibility study of a whatsapp-delivered transtheoretical model-based intervention to promote healthy eating habits for male firefighters in Hong Kong : a cluster randomized controlled trial
Advisors: Cheung, Kin (SN)
Degree: DHSc
Year: 2021
Subject: Fire fighters -- Nutrition
WhatsApp (Application software)
Health promotion
Health behavior
Hong Kong Polytechnic University -- Dissertations
Department: Faculty of Health and Social Sciences
Pages: 197 pages : color illustrations
Language: English
Abstract: Background: High prevalence of obesity and cardiovascular diseases, which are the common risk factors of sudden cardiac death, affects firefighters' health. The prevalence rates of overweight and obesity are ranging respectively from 22% to 60%, 40%, and 15% in the United States, Hong Kong, and Brazil. Considering the firefighters' responsibility to protect the public, their health should be our first concern. Healthy eating is the most essential way to minimize the mortality rate from cardiovascular diseases. Health promotion using the Transtheoretical Model on healthy eating including increasing fruit and vegetable (F&V) consumption, has been proven effective to motivate behavioral changes in diverse populations. Traditional methods of delivery such as printed promotion pamphlets and face-to-face workshops that promote healthy eating for firefighters might have limitations because of unpredicted call outs. Owing to the rapid increase in the number of Internet users worldwide, social networking systems, such as WhatsApp, serve as a useful tool in delivering health promotion programs. However, using WhatsApp-delivered Transtheoretical Model-based intervention to promote healthy eating habits among firefighters is limited.
Aims: This study aimed to determine the feasibility of using Transtheoretical Model-based stage-matched teaching materials via WhatsApp to promote healthy eating and to examine its potential effects on promoting healthy eating habits among firefighters in Hong Kong.
Methods: This feasibility study used a two-armed clustered randomized control trial as its research design by using convenience and snowball sampling. A total of 48 participants were recruited and randomly assigned to either control (transtheoretical Model-based promotion pamphlet) (n = 25) or intervention (transtheoretical Model-based promotion pamphlet and stage-matched teaching materials via WhatsApp) (n = 23) groups. Considering that 48 participants met the inclusion criteria, no participants were excluded. The outcomes of changes in healthy eating habits were assessed using a self-administrative questionnaire, anthropometric measurements and qualitative survey. The primary outcome was eating habits by using self-reported questionnaire, including measurement of portion size and frequency of fruit and vegetable intake in a week. The secondary outcomes were the stage of change in eating habits, decisional balance in eating habits, eating self-efficacy by using self-reported questionnaire and anthropometric measurement as measured by a researcher. Changes in healthy eating habits and anthropometric measurements were assessed at baseline and at 3 months and 6 months after intervention. Feedback from participants on the feasibility at 3 months and 6 months after intervention were collected. Intention-to-treat was not applied as no missing data was found among 45 participants. The effect of time and intervention on both primary and secondary outcomes were tested using appropriate non-parametric test including Mann-Whitney U test for comparing control and intervention groups F&V consumption and Friedman test for the change of waist-to-hip ratio (WHR) over time. Test results with p<0.05 were considered as statistically significant. Considering the limited sample size, subgroups analysis was not performed. The data from the qualitative survey were used to identify whether the program addressed the participants' needs through a specific and appropriate method.
Results: A total of 45 participants completed this study. The results revealed that the program was feasible in terms of acceptability, practicality, implementation, and preliminary effects of outcomes. Furthermore, the program delivered via WhatsApp had significantly increased F&V intakes and improved WHR. Results demonstrated that participants between intervention and control groups had significantly increased consumption of F&V (fruit: d = 0.40, p = 0.001, vegetables: d = 0.40, p < 0.05). The proportions of having more than two servings of F&V in the intervention group have increased from 0 (0%) to 14 (70%) respectively. The proportions of post-action stage in the intervention group have increased from 5 (25%) to 18 (90%), respectively. Furthermore, the proportions of having more than two servings of F&V in the control group have increased from 1 (4%) to 6 (20%) respectively. The proportions of post-action stage in the intervention group has increased by 260%. The WHR in the intervention group decreased from 0.9±0.32 to 0.8±0.04 (d = 0.44, p = 0.05), while the WHR of participants in the control group changed from 0.86±0.43 to 0.86±0.05.
Conclusion: To the best of our knowledge, this study is the first to examine the feasibility of using WhatsApp as a tool to deliver Transtheoretical Model-based intervention to promote healthy eating habits for firefighters and improve waist-to-hip ratio. Results of this feasibility study can be used to modify the full-scale study.
Rights: All rights reserved
Access: restricted access

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