Health wearable devices for weight and BMI reduction in individuals with overweight/obesity and chronic comorbidities：systematic review and network meta-analysis
http://orcid.org/0000-0002-5313-7284Daniel J McDonough,
Correspondence to Dr Zan Gao, University of Minnesota Twin Cities, Minneapolis, MN 55455, USA; firstname.lastname@example.org
BMJ Learning - Take the Test
Objective To analyse the comparative effectiveness of different health wearable-based physical activity（PA）promotion intervention strategies against each other and control for reducing body weight and body mass index（BMI）in individuals with overweight/obesity and chronic comorbidities.
Design Systematic review and network meta-analysis（PROSPERO identifier：CRD42020158191）.
Data sources We performed two independent searches from December 2019 to September 2020 in PubMed, MEDLINE, Scopus, Web of Science, Central Register of Controlled Trials, EMBASE and PsycINFO databases for articles published in English between 2007 and 2020.
Eligibility criteria for selecting studies Inclusion criteria were based on the PICOS framework. We included randomised controlled trials of health wearable-based interventions using two or more PA intervention arms/strategies and compared their effects on participants’ body weight（kg）and BMI（kg/m2）with a control group. Data were analysed using a Bayesian network meta-analysis to directly and indirectly compare the effects of the six different intervention strategies（comparators）. The six comparators were：（1）control group（ie, usual care, waitlist）;（2）comparison group（ie, traditional, non-health wearable PA interventions）;（3）commercial health wearable-only intervention（eg, Fitbit, Polar M400）;（4）research grade health wearable-only intervention（ie, accelerometers or pedometers）;（5）multicomponent commercial health wearable intervention（eg, Fitbit + nutrition counselling）; and（6）multicomponent research grade health wearable intervention. The results were reported as standardised mean differences（SMDs）with associated 95% credible intervals（CrIs）.
Results From 641 screened records, 31 studies were included. For body weight reduction in individuals with overweight/obesity and chronic comorbidities, accelerometer/pedometer-only（SMD −4.44, 95% CrI −8.94 to 0.07）and commercial health wearable-only（SMD −2.76, 95% CrI −4.80 to −0.81）intervention strategies were the most effective compared with the three other treatments and control. For BMI reduction, multicomponent accelerometer/pedometer（SMD −3.43, 95% CrI −4.94 to −2.09）and commercial health wearable-only（SMD −1.99, 95% CrI −4.95 to 0.96）intervention strategies were the most effective compared with the other four conditions.
Conclusion Health wearable devices are effective intervention tools/strategies for reducing body weight and BMI in individuals with overweight/obesity and chronic comorbidities.