Table 1. Study characteristics.
| Author | Country | Population | POAF | SR | Mean age | MVD POAF | MVD SR | Definition of AF | Method for measurement of vitamin D | Type of study | Type of surgery | |
| POAF | SR | |||||||||||
| Skuladottir et al 2016 | Iceland | 118 | 66 | 52 | 70·5(med) | 64(med) |
19.862 ± 8.823 |
17.748 ± 9.534 |
Continuous electrocardiaographic monitoring | MS/MS Vitamin D Kit | Nested case-control | CABG and/or valvular surgery |
| Emren et al 2016 | Turkey | 283 | 72 | 211 | 70 ± 8.6 | 61 ± 9 | 15.6 ± 7.4 | 19.1 ± 9.1 | ECG | Chemiluminescence immuno assay | Nested case-control | CABG |
| Shadvar et al 2016 | Iran | 50 | 25 | 25 | 69 ± 0.3 | 72 ± 0.8 | 27.4 ± 2.22 | 28.2 ± 1.18 | Holter monitoring | Not mentioned | Nested case-control | CABG |
| Gode et al 2016 | Turkey | 90 | 15 | 75 | 59.1 ± 5.4 | 58.4 ± 9.1 | 9.0 ± 5.0 | 15.0 ± 8.4 | Five-lead telemetry | Not metioned | Nested case-control | CABG |
| Cerit et al 2017 | Cyprus | 128 | 41 | 87 | 67.6 ± 8.6 | 63.9 ± 9.8 | 19.9 ± 6.1 | 26 ± 8.2 | Daily electrocardiographic recordings | Chemiluminescence immunoassay | Retrospective cohort | CABG |
| total | 669 | 219 | 450 | |||||||||
Abbreviations: MVD, mean vitamin D; POAF, postoperative atrial fibrillation; SR, sinus rhythm