Table 1.
Descriptive statistics and covariate balance for 5526 patients undergoing intertrochanteric hip fracture surgery using a cephalomedullary nail, by nail length (2009–2014)
| Characteristica | Long nail (n = 3108) | Short nail (n = 2418) | Preweight standardized difference | Postweight standardized difference |
|---|---|---|---|---|
| Continuous, mean (SD) | ||||
| Age, y | 80.6 (11.0) | 81.2 (10.8) | 0.06 | 0 |
| BMI, kg/m2 | 24.6 (5.4) | 24.1 (5.1) | 0.11 | 0.01 |
| ASA classification | 2.8 (0.6) | 2.9 (0.6) | 0.10 | 0 |
| Categorical, no. (%) | ||||
| Female sex | 2170 (69.8) | 1698 (70.3) | 0.01 | 0 |
| Race/ethnicity Asian | 141 (4.5) | 225 (9.3) | 0.18 | 0 |
| Hispanic | 367 (11.9) | 202 (8.4) | 0.11 | 0.01 |
| White | 2465 (79.6) | 1870 (77.7) | 0.04 | 0.01 |
| Other | 124 (4.0) | 111 (4.6) | 0.02 | 0 |
| Interlocking screws | 1937 (62.3) | 2109 (87.2) | 0.61 | 0.01 |
a
Missing data: BMI (n = 29), ASA (n = 74), sex (n = 1), race/ethnicity (n = 21).
ASA = American Society of Anesthesiologists; BMI = body mass index; preweight = before applying propensity score weights; postweight = after applying propensity score weights; SD = standard deviation.