A Cluster Randomized Controlled Trial Feasibility Study of a WhatsApp-Delivered Intervention to Promote Healthy Eating Habits in Male Firefighters.

This cluster randomized controlled trial (CRCT)-designed study aimed to explore the feasibility of a promotion pamphlet and/or WhatsApp as a suitable mode of delivery to promote healthy eating habits with fruit and vegetables (F&V) among firefighters. Convenience and snowball sampling methods were used. Forty-five firefighters from 23 fire stations were recruited and they all received the printed pamphlet, while the intervention group participants (n = 20) received additional teaching material through WhatsApp every two weeks for eight weeks. Feasibility outcomes included retention, practicality, and implementation. The participants reported high levels of satisfaction with the intervention. There were significant improvements in the mean numbers of days consuming F&V (p = 0.002; p = 0.031) in the intervention group, and for fruit consumption (p = 0.033) in the control group between the baseline (T0) and 3 months after completion of intervention (T1). High levels of participants' satisfaction with the intervention revealed that a full-scale CRCT of the WhatsApp-delivered intervention promoting healthy eating could be feasible, especially as a means of increasing the numbers of days they consumed F&V and the numbers of servings of these consumed per day.