Author: Lai, Kam-wa Dennis
Title: The effect of a Facebook-based weight management program for obese working adults in Hong Kong
Advisors: Wong, Thomas K. S. (FHSS)
Shae, Wan-chaw (FHSS)
Degree: DHSc
Year: 2016
Subject: Weight loss -- China -- Hong Kong.
Health promotion -- China -- Hong Kong.
Online social networks.
Hong Kong Polytechnic University -- Dissertations
Department: Faculty of Health and Social Sciences
Pages: xvi, 238 pages
Language: English
Abstract: Background: Obesity is a global health problem associated with premature mortality and multiple co-morbidities. It severely impairs the quality of life of people and causes huge economic and disease burdens across developed and developing countries. Over 38% of Hong Kong Chinese adult population is either overweight or obese. Conventional lifestyle weight loss interventions in primary care settings impose participation barriers due to cost, time, transportation and job commitment. With its popularity worldwide, social media may represent a promising resource to facilitate education, engagement and social support for health interventions at a population level. Controlled trials using this resource for weight management in Hong Kong are limited. Intervention: The intervention was guided by the transtheoretical model to motivate obese working adults to higher stages of behavioral changes by addressing their various needs on education, coping skills, barriers, benefits, confidence and social support for lifestyle modification with partnership from healthcare professionals. Aim: To determine the feasibility and efficacy of a 6-month weight management program for obese working adults in Hong Kong through a popular commercial social networking site - Facebook. Methods: This study involved a randomized controlled trial using consecutive sampling. Fifty-nine full-time obese university employees aged 18 to 60 years with a body mass index of 25 to 40 kg/m2 (71% male, age 43.17±9.37 years, BMI 29.02±3.27 kg/m2) were recruited and randomly assigned to either a Facebook-based weight management (FBWM) intervention group (n=30) or a paper-based health education control group (n=29). Participants in the FBWM group additionally joined a private Facebook group in which one nutritionist and one Chinese medicine practitioner acted as health partners to educate and motivate participants towards East-meets-West healthy lifestyle. Outcome measures were changes in body weight, body mass index (BMI), waist circumference (WC), percentage of weight loss, stages of change, decisional balance, self-efficacy, social support, dietary intakes and physical activity. Data were collected at baseline, 3 and 6 months and information of FBWM participant engagement and satisfaction was obtained after intervention. Analyses were performed with intention to treat for missing data. Multivariate analysis of variance (MANOVA), independent t-test, Chi-square/ Fisher's exact test and Mann-Whitney U test were applied for between-group comparisons whereas repeated measures ANOVA and Friedman test were used to analyze data within-group over time.
Results: Repeated measures analyses showed that only the intervention group had within-group significant decreases in weight (-1.12±2.75 kg), BMI (-0.39±0.95) and WC (-3.33±4.58 cm) by 6 months. A significant difference was found at 3 months in primary outcomes between participants in the intervention and control groups (F (3,55) = 2.89, p < 0.05; Wilk's Λ = 0.864, partial η2 = 0.14) but did not sustain at 6 months. More intervention participants than the controls achieved the 5% or more weight loss goal (20% vs. 7%) at 6 months. Compared to the control group, the intervention group had significantly more participants shifted to the Action and Maintenance stages after intervention. The intervention group increased vegetable intakes at 3 months (p<0.05). No significant improvement in self-efficacy and social support through an online platform was detected after intervention. Participant retention rate was 93% and about half (48%) of the participants logged in the Facebook group every day. Results of post-study survey indicated that 86% respondents found FBWM program useful and 82% would recommend it to friends. Conclusions: Despite mixed results between groups, findings from this study suggest a weight management program through social networking sites feasible and effective to certain degree for Hong Kong obese working individuals. Effective measures for enhancement of self-efficacy, social support, self-monitoring should be explored with different genders and diverse samples in social networking sites. Given that social media has potential for massive reach and integrates into our daily life, efforts to further understand how this resource can be used for health promotion should be pursued.
Rights: All rights reserved
Access: restricted access

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