JMIR Publications

ABSTRACT

Background:

Physical inactivity is a preventable risk factor for several chronic diseases and one of the driving forces behind the growing global burden of disease. Recent evidence has shown that interventions using mobile smartphone applications (apps) can promote a significant increase in physical activity (PA) levels. However, the accuracy and reliability of using apps is unknown.

Objective:

The aim of our review is to determine the accuracy and reliability of using mobile apps to measure PA levels in young people. We conducted a systematic review guided by PRISMA.

Methods:

Studies published from 2007 to 2020 were sourced from eight databases (Ovid MEDLINE, Embase (Elsevier), Cochrane Library (Wiley), PsychINFO (EBSCOhost), CINAHL (EBSCOHost), Web of Science (Clarivate), SPORTDiscus (EBSCOhost), and IEEE Xplore Digital Library database). Studies conducted in young people, aged 10-24 years without chronic illness that evaluated a mobile app’s ability to measure PA. Primary outcomes include validity, reliability and/or responsiveness of the measurement approach. Duplicate screening was conducted for eligibility, data extraction and assessing the risk of bias. Results are reported as a systematic review. The main outcome measures assessed were: total PA time (mins/day or mins/week), total moderate-vigorous PA per week, daily step count, intensity measure (heart rate), and frequency measure (days per week).

Results:

Of the 149 identified studies, five met inclusion criteria (n=322 participants, 58% female; mean age 14±3 years). Three studies measured criterion validity and compared PA measured via apps against an Actigraph accelerometer. The two studies that reported on construct validity reported a significant difference between self-reported PA and the objective measure. Only one of the five apps examined is available to the public, and though this app was highly accepted by young people, the app recorded PA to be significantly different to participants’ self-reported PA.

Conclusions:

Overall, few studies assess the reliability, validity and responsiveness of mobile apps to measure PA in healthy young people, with studies typically only reporting on one measurement property. Of the three studies that measured validity, all concluded mobile phones to be an acceptable and valid tool. More research is needed into the validity and reliability of smart-phone apps to measure PA levels in this population, as well as populations with other characteristics, including age groups and those with chronic disease. Clinical Trial: Systematic review registration: PROSPERO CRD42019122242.