Table 1.
Characteristics of the 16 included randomized controlled trial articlesa.
| Study | Trial arms (n); country | Sample size (n) | Age (years), mean | Proportion of males, % | Baseline weight (kg), mean; baseline BMI (kg/m2), mean | Attrition rateb, %; presence of group differencesc | Missing data management; protocol registration; funding | Reported on SESd; educational level |
| Carter et al [18], 2013 | 3; United Kingdom | 128 | 41.9 | 22.7 | 96.9; 34.2 | 38.3; yes | ITTe; yes; yes | Yes; yes |
| Duncan [19], 2020 | 3; Australia | 116 | 44.5 | 29.3 | 90.7; 31.7 | 46.6; yes | ITT; yes; yes | Yes; yes |
| Dunn et al [17], 2019 | 2; United States | 43 | 42.4 | 9.3 | NSf; 34.5 | 30; NS | ITT; yes; yes | Yes; yes |
| Eisenhauer et al [22], 2021 | 2; United States | 80 | 54.2 | 100 | 114.1; 35.6 | 7.5; NS | NS; yes; yes | Yes; yes |
| Falkenhain et al [23], 2021 | 2; United States | 155 | 41 | 29 | 94.4; 33.5 | 25.2; nil | ITT; yes; yes | Yes; yes |
| Godino et al [30], 2016 | 2; United States | 404 | 22.7 | 29.7 | 80.7; 29 | 15.6; nil | ITT; yes; yes | Yes; yes |
| Johnston et al [26], 2013 | 2; United States | 292 | 46.5 | 10.2 | 90.1; 33 | 12; nil | ITT; no; yes | Yes; yes |
| Kurtzman et al [29], 2018 | 3; United States | 196 | 41.4 | 14.3 | 102.5; 36.2 | 4.5; NS | ITT; yes; yes | Yes; yes |
| Martin et al [25], 2015 | 2; United States | 40 | 44.4 | 17.5 | 80.3; 29.8 | 5.0; NS | ITT; yes; yes | NS; NS |
| Patel et al [24], 2019 | 3; United States | 105 | 42.7 | 16 | 89.6; 31.9 | 26.7; NS | ITT; yes; yes | Yes; yes |
| Rosas et al [31], 2020 | 2; United States | 192 | 50.2 | 38.2 | 87.1; 32.4 | 0.5; NS | PPg; yes; yes | Yes; yes |
| Ross et al [27], 2016 | 3; United States | 80 | 51.1 | 13.8 | 89.3; 33 | 10; NS | ITT; yes; yes | NS; NS |
| Spring et al [28], 2017 | 3; United States | 96 | 39.3 | 15.6 | 94.8; 34.6 | 13.5; yes | ITT; yes; yes | NS; Yes |
| Tanaka et al [20], 2018 | 2; Japan | 112 | 46.3 | 99.1 | 83.2; 28 | 27.7; NS | ITT; yes; yes | NS; NS |
| Turner-McGrievy et al [16], 2017 | 2; United States | 81 | 48.1 | 17.3 | NS; 33.4 | 25; nil | ITT; yes; yes | Yes; yes |
| Zhou et al [21], 2021 | 3; China | 750 | 70.1 | 46.1 | 70.6; 27.5 | 14.4; NS | NS; yes; yes | NS; Yes |
aDetails of the group differences, protocol registration, funding, reports on socioeconomic status, and educational levels are presented in Multimedia Appendix 3 [16-31].
bAttrition rate by last outcome measurement time point.
cGroup differences between participants who were retained and dropped out.
dSES: socioeconomic status.
eITT: intention-to-treat.
fNS: not specified.
gPP: per-protocol analysis.