JMIR Publications

ABSTRACT

Background:

Even though many people have initial success in changing their dietary and/or physical activity behaviors to lose weight, few successfully maintain their lost weight over the longer-term. Smartphones have the potential to deliver weight loss management programs that can encourage self-monitoring while also providing some behavioral therapy to assist users in developing personal skills that may be necessary for improved longer-term weight-loss maintenance.

Objective:

The aim of this study was to evaluate a program supporting weight maintenance which uses a behaviorally-based smartphone app to manage weight, food, exercise, mood and stress.

Methods:

: In a randomized controlled trial over 24 weeks, the full version of the app (MotiMate) was compared to a control app (monitoring only; excluding mood/stress) for its effect on weight, diet, and psychological wellbeing. Both study apps had the same visual appearance. The control version included only features to track weight, food intake and exercise with limited feedback and no encouraging/persuasive features. The intervention app included more persuasive and interactive features to help users track their weight, food intake and physical activity and prompted users to enter data each day through notifications and included a mood and stress workshopping tool. Clinic visits occurred at baseline (week 0), 4 weeks, 8 weeks, 12 weeks and 24 weeks. At all visits the clinical trial manager recorded body weight and participants then completed a computer-delivered survey which measured psychological and lifestyle outcomes. Objective app usage data was also recorded throughout the trial.

Results:

Eighty-eight adults who had lost and maintained at least 5% of their body weight within last 2 years were randomised. Of starters, 75% (n=66) were female and 69.3% (n=61) completed week 24 with no differences in drop-out by condition (χ2(1,87)=0.70, P=0.490). Mixed models suggested no significant changes in weight or psychological outcomes over 24 weeks regardless of condition. Of completers, 52.5% (n=32) remained within 2% of their starting weight. Significant increases occurred over 24 weeks for satisfaction with life and weight-loss self-efficacy regardless of app condition. Diet and physical activity behaviors did not vary by app or week. Negative binomial models indicated that those receiving the full app remained active users of the app for 46 days longer than controls (P=0.017). Users of the full version of the app also reported that they felt more supported than those with the control app (P=0.006).

Conclusions:

While some aspects of the intervention app showed promise, there were few observable effects on behavioral and psychological outcomes. Future evaluation of the app may need to implement more progressive research methods or target more specific populations in order to better understand the utility of the coping interface. Clinical Trial: Australian New Zealand Clinical Trials Registry (ACTRN12614000474651)