Evaluating the feasibility and effectiveness of self-monitoring of health among Samoan women: a randomized trial

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Erica Kocher
Mayur Desai
Anna Rivara
Take Naseri
Nicola Hawley


Samoa, Exercise, Body Mass Index, Psychosocial Factors, Self-monitoring


Objective: Self-monitoring technologies that help individuals track their health have proven effective in high-income countries but have not been widely tested or marketed in the Pacific islands. We conducted a pilot randomized controlled trial in Samoa to investigate the feasibility and acceptability of step-counters and digital scales.

Methods: The trial enrolled 44 Samoan women (31-40 years), without previously diagnosed chronic conditions (hypertension, diabetes, etc.), who reported motivation to become more physically active. After measuring daily step counts for one week in the absence of feedback, participants were randomly assigned to one of three groups for a four-week intervention period: 1) FitBit Zip® step-counter, 2) digital BodyTrace© scale, or 3) both devices. Outcomes of interest were device use, psychosocial indicators of health, daily step counts, and body mass index, measured at baseline and post-intervention.

Results: Participants who received scales used them a median of 5.5 times during the four-week intervention period. While FitBits were used a majority of days during the baseline period, there was significant decline in use during the intervention. In all groups, Health Locus of Control, Self-Efficacy for Exercise, and Weight Efficacy improved. However, while the Scale Only group reported improved health-related quality of life, the two groups that used FitBits either did not significantly change or significantly decreased in their assessments of this measure. No group demonstrated change in average daily step counts during the intervention; BMI increased among the two groups using the scales.

Conclusions: Results suggest that self-monitoring technologies are acceptable in Samoa and generally improve psychosocial indicators of health. Further research is necessary to assess their effectiveness as an intervention tool and to determine how best to sustain device use over time. The significant increase in BMI over the relatively short intervention period highlights the importance of developing effective intervention approaches in this setting.

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