Table 2.
Mixed effects logistic model showing odds of receiving total hip arthroplasty (THA) among those deemed eligible by NICE guidelines
| Variable | OR (95% CI) | P value |
|---|---|---|
| Age (for each increasing year of life) | 0.88 (0.87 to 0.88) | <0.001 |
| AMTS: | ||
| 10 (maximum correct answers) | 1.0 (ref) | — |
| 9 | 0.69 (0.62 to 0.77) | <0.001 |
| 8 (borderline for cognitive impairment) | 0.49 (0.41 to 0.58) | <0.001 |
| ASA score: | ||
| 1 (healthy person) | 1.0 (ref) | — |
| 2 (mild systemic disease) | 0.74 (0.66 to 0.84) | <0.001 |
| Mobility: | ||
| Walks independently without aids | 1.0 (ref) | — |
| Walks with aid of one stick | 0.32 (0.28 to 0.35) | <0.001 |
| Sex: | ||
| Female | 1.0 (ref) | — |
| Male | 0.85 (0.77 to 0.93) | 0.002 |
| Day of admission: | ||
| Saturday | 0.86 (0.75 to 0.99) | 0.03 |
| Sunday | 0.88 (0.76 to 1.12) | 0.09 |
| Monday | 0.93 (0.81 to 1.07) | 0.32 |
| Tuesday | 0.94 (0.82 to 1.08) | 0.41 |
| Wednesday | 1.00 (ref) | — |
| Thursday | 1.00 (0.87 to 1.15) | 0.97 |
| Friday | 0.85 (0.74 to 0.98) | 0.03 |
| Weekend admission* | 0.90 (0.83 to 0.98) | 0.01 |
| Fifth of deprivation: | ||
| 1 (least deprived) | 1.0 (ref) | — |
| 2 | 0.98 (0.88 to 1.09) | 0.68 |
| 3 | 0.92 (0.82 to 1.03) | 0.13 |
| 4 | 0.82 (0.72 to 0.92) | 0.001 |
| 5 (most deprived) | 0.76 (0.66 to 0.88) | <0.001 |
| Date of surgery (to most recent, increasing in 6 month intervals) | 1.13 (1.10 to 1.15) | <0.001 |
| Fracture volume of hospital (increasing in tenths) | 1.02 (0.97 to 1.08) | 0.46 |
*Defined as Friday or Saturday admission, as surgery most commonly occurs on day after admission. “Weekday” was therefore defined as Sunday-Thursday. “Weekend” included in logistic model as dichotomous variable and day of week excluded as collinear.