Table 2. Characteristics of the studies included for the meta-analysis of omentin-1 concentrations in diabetes mellitus.
| Study | Study design | Male, n(%) | BMI | Mean Age | Type | Methods | Frozen | NOS |
|---|---|---|---|---|---|---|---|---|
| Abd-elbaky 2015 | Case-control | 80(100%) | 32.4±1.4 | 42.0±3.0 | T2DM | ELISA | −80℃ | 7 |
| Abdelraoufkorany 2018 | Case-control | 12(48%) | 26.6±2.9 | 56.5±7.2 | T2DM | ELISA | NR | 6 |
| Abell 2017 | Case-control | 25(0%) | 28.0±2.6 | 32.7±3.3 | GDM | ELISA | −80℃ | 7 |
| Ahmed 2018 | Case-control | 40(100%) | 28.8±6.8 | 57.6±15.6 | T2DM | ELISA | −20℃ | 8 |
| Akbarzadeh 2012 | Case-control | 41(46%) | 27.6±4.3 | 40.5±9.6 | T2DM | ELISA | −70℃ | 7 |
| Akour 2016 | Case-control | 68(66%) | 33.3±3.0 | 51.0±4.8 | T2DM | ELISA | −80℃ | 8 |
| Cai 2008 | Case-control | 35(51%) | 28.5±2.7 | 48.8±11.7 | T2DM | ELISA | −80℃ | 8 |
| Dayem 2015 | Case-control | 62(100%) | 24.9±4.2 | 16.3±1.5 | T1DM | ELISA | NR | 6 |
| El-mesallamy 2011 | Case-control | 35(66%) | 29.0±0.8 | 58.0±1.0 | T2DM | ELISA | −80℃ | 7 |
| Elsaid 2018 | Case-control | 60(0%) | 39.4±7.0 | 49.5±6.0 | T2DM | ELISA | −20℃ | 8 |
| Franz 2018 | Case-control | 96(0%) | 28.0±6.6 | 34.1±7.4 | GDM | ELISA | −80℃ | 9 |
| Greulich 2013 | Case-control | 78(100%) | 28.9±1.1 | 71.9±2.4 | T2DM | ELISA | −80℃ | 7 |
| Hayashi 2018 | Case-control | 246(58%) | 25.0±2.2 | 65.0±5.7 | T2DM | ELISA | NR | 5 |
| Herder 2017 | Case-control | 34(52%) | 27.7±4.0 | 68.6±4.9 | T2DM | ELISA | NR | 6 |
| Kahwaji 2017 | Cross sectional | 35(34%) | 33.5±5.9 | 51.9±10.9 | T2DM | ELISA | −80℃ | 7 |
| Kocijancic 2015 | Case-control | 57(34%) | 25.6±3.7 | 70.0±3.0 | T2DM | ELISA | NR | 6 |
| Lewandowski 2010 | Case-control | 20(100%) | 30.3±3.1 | 29.7±3.7 | GDM | ELISA | NR | 6 |
| Madsen 2015 | Case-control | 3(30%) | 27.6±2.7 | 56.0±2.0 | T2DM | ELISA | −80℃ | 7 |
| Mierzyński 2018 | Case-control | 63(0%) | 24.8±2.5 | 28.6±5.1 | GDM | ELISA | −70℃ | 8 |
| Motawi 2017 | Case-control | 23(51%) | 23.1±1.8 | 53.7±7.6 | T2DM | ELISA | NR | 6 |
| Nurten 2018 | Case-control | 115(47%) | 23.9±9.2 | 13.0±3.9 | T1DM | ELISA | −80℃ | 7 |
| Pan 2010 | Case-control | 30(55%) | 25.9±3.3 | 39.9±4.8 | T2DM | ELISA | −70℃ | 7 |
| Polkowska 2016 | Case-control | 5(50%) | 18.3±5.7 | 10.4±2.8 | T1DM | ELISA | NR | 6 |
| Tan 2008 | Case-control | 19(100%) | 25.1±3.3 | 30.3±4.9 | T1DM | ELISA | NR | 6 |
| Tekce 2014 | Case-control | 36(66%) | 26.1±4.8 | 55.2±8.9 | T2DM | ELISA | −80℃ | 8 |
| Tsiotra 2018 | Case-control | 15(100%) | 36.0±1.5 | 36.1±1.2 | GDM | ELISA | −80℃ | 7 |
| Urbanova 2014 | Case-control | 11(0%) | 52.6±2.6 | 56.9±2.8 | T2DM | ELISA | −80℃ | 6 |
| Wan 2015 | Case-control | 60(100%) | 23.8±3.0 | 58.7±9.0 | T2DM | ELISA | −80℃ | 7 |
| Yan 2011A | Case-control | 18(51%) | 24.3±0.6 | 55.5±1.7 | T2DM | ELISA | −70℃ | 7 |
| Yan 2011B | Case-control | 13(43%) | 24.4±3.3 | 53.1±7.7 | T2DM | ELISA | −80℃ | 7 |
| Yoo 2011 | Case-control | 10(33%) | 23.9±2.3 | 53.1±6.8 | T2DM | ELISA | −80℃ | 7 |
| Zhang 2014 | Case-control | 20(57%) | 32.4±5.5 | 65.1±10.7 | T2DM | ELISA | −80℃ | 8 |
| Abd El Dayem 2015 | Case-control | 31(50%) | 24.9±4.2 | 16.3±1.5 | T1DM | ELISA | NR | 7 |
| Nassif 2013 | Case-control | 19(87%) | 24.3±0.3 | 48.9±1.5 | T2DM | ELISA | −80℃ | 5 |
| Matloch 2018 | Case-control | 7(78%) | 30.4±3.59 | 67.0±8.76 | T2DM | ELISA | −80℃ | 5 |
| Gürsoy 2010 | Case-control | 0(0%) | 30.5±4.8 | 52.8±10.7 | T2DM | ELISA | −75℃ | 6 |
| Flehmig 2014 | Cross sectional | 34(50%) | 46.9±10.1 | 53.0±13.0 | T2DM | ELISA | NR | 7 |
| Dogan 2016 | Case-control | 7(47%) | 22.8±1.9 | 48.3±6.1 | T2DM | ELISA | −80℃ | 5 |
| Komosinska-vassev 2019 | Case-control | 23(55%) | 33.1±4.1 | 61.0±5.6 | T2DM | ELISA | −20℃ | 7 |
| Rathwa 2019 | Case-control | 123(49%) | 28.2±5.0 | 55.9±10.5 | T2DM | ELISA | −20℃ | 7 |
| Tuttolomondo 2019 | Case-control | 23(57%) | 29.4±5.5 | 61.4±11.4 | T2DM | ELISA | −80℃ | 6 |
| Souvannavong-vilivong 2019 | Case-control | 0(0%) | 29.0±5.0 | 38.2±1.3 | GDM | ELISA | −70℃ | 6 |
Characteristics of eligible studies are shown in each independent case. NOS, Newcastle-Ottawa Scale; BMI, Body Mass Index; ELISA, enzyme linked immunosorbent assay; NR, not report; T1DM, type 1 diabetes mellitus; T2DM, type 2 diabetes mellitus; GDM, gestational diabetes mellitus.