Risk factors for mild traumatic brain injury in Calgary MMA athletes from January 2010 to December 2015
| Variables | Unadjusted OR (95% CI) | P value | Adjusted OR (95% CI)* | P value |
| Set 1 | ||||
| Age (years) | 0.99 (0.95 to 1.04) | 0.776 | 0.99 (0.95 to 1.04) | 0.792 |
| Sex | ||||
| Female | Reference | – | Reference | – |
| Male | 1.49 (0.34 to 6.48) | 0.597 | 0.88 (0.18 to 4.28) | 0.87 |
| Weight (pounds) | 1.01 (1.00 to 1.02) | 0.01 | 1.01 (1.00 to 1.02) | 0.063 |
| Bout length (seconds) | 0.997 (0.996 to 0.998) | <0.01 | 0.997 (0.996 to 0.998) | <0.01 |
| Bout type | ||||
| Non-title | Reference | – | Reference | – |
| Title | 1.40 (0.63 to 3.10) | 0.407 | 2.00 (0.90 to 4.65) | 0.108 |
| Set 2 | ||||
| Referee | ||||
| <50 bouts experience | Reference | – | Reference | – |
| ≥50 bouts experience | 1.08 (0.66 to 1.75) | 0.766 | 1.01 (0.56 to 1.83) | 0.964 |
| Country of origin | ||||
| Canada | Reference | – | Reference | – |
| Non-Canadian | 1.55 (0.83 to 2.90) | 0.17 | 1.60 (0.82 to 3.13) | 0.172 |
| Prior experience (number) | 1.00 (0.97 to 1.04) | 0.884 | 0.98 (0.94 to 1.02) | 0.288 |
| Level of competition | ||||
| Amateur | Reference | – | Reference | – |
| Professional | 1.38 (0.88 to 2.17) | 0.165 | 1.53 (0.88 to 2.65) | 0.128 |
| Matchmaker | ||||
| Others | Reference | – | Reference | – |
| Dominant matchmaker | 0.81 (0.50 to 1.30) | 0.374 | 0.84 (0.48 to 1.47) | 0.538 |
*Multivarible logistic regression of injured to non-injured after controlling for other variables in the set.
MMA, mixed martial arts.