2.7. Data Synthesis

To synthesise the data, studies were split into “effectiveness studies” and “feasibility/acceptability studies”. Effectiveness studies were those that provided an outcome measure of PA. The term “effectiveness studies” was chosen as some studies that measured PA did not claim to be an intervention. Studies that reported the experiences of children/adolescents using the wearable, but did not measure PA, were considered feasibility/acceptability studies. A narrative review was conducted for effectiveness studies, given that the heterogeneity of study designs and outcomes did not permit a meta-analysis. A thematic synthesis was conducted for feasibility/acceptability studies in which the authors provided quotations from participants and/or the authors’ interpretations of participant experiences using a wearable (as used previously by Fletcher et al. [44]). The thematic synthesis followed the three stages outlined by Thomas and Harden, which are presented in Table 1 [45].

Stages of thematic synthesis [45].

Line-by-line coding of the findings of primary studies.

The development of “descriptive” themes from the free codes.

The development of “analytical” themes from the descriptive themes.

Line-by-line coding was carried out by one reviewer (A.V.C.) using the NVivo software (QSR International, Melbourne, Australia), and the meaning and content of each code was agreed upon by a second reviewer (J.H.). One reviewer (A.V.C.) developed descriptive themes from the codes by grouping those that were similar together and further developed these into analytical themes by relating them to the reviews’ aims. These codes were discussed and refined with the help of J.H. This approach has been used previously [44] and was chosen as an inductive approach was taken.