Table 3. Factors Associated With 30-Day Appendectomy in Univariate and Multivariable Models.
| Factor | Odds ratio (95% CI)a | |
|---|---|---|
| Univariate | Base + R + A | |
| Age, per 1-y increase | 1.01 (0.99-1.02) | 1.00 (0.98-1.01) |
| Female sex (vs male sex) | 1.16 (0.80-1.68) | 1.53 (1.01-2.31) |
| BMI (vs <25) | ||
| 25-35 | 1.77 (1.14-2.75) | 1.60 (0.99-2.60) |
| >35 | 0.75 (0.42-1.34) | 0.68 (0.37-1.24) |
| Symptoms duration ≥1 d (vs <1 d) | 0.89 (0.58-1.36) | 0.81 (0.51-1.31) |
| Mean pain in the previous 7 d, per 1-point increase | 1.07 (1.00-1.14) | 1.06 (0.99-1.14) |
| White blood cell count, per 1000-cells/μL increase | 1.04 (0.99-1.09) | 1.03 (0.98-1.09) |
| Feverb | 1.31 (0.87-1.97) | 1.28 (0.82-1.98) |
| Nausea, vomiting, or anorexiab | 0.83 (0.52-1.32) | 0.69 (0.42-1.16) |
| Appendiceal diameter, per 1-mm increase | 1.14 (1.06-1.22) | 1.09 (1.00-1.18) |
| Perforation, abscess, or fat strandingb | 1.56 (0.94-2.59) | 1.14 (0.66-1.98) |
| Appendicolithb | 2.56 (1.73-3.79) | 1.99 (1.28-3.10) |
Abbreviation: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared).
SI conversion factor: To convert white blood cells to ×109/L, multiply by 0.001.
a
All odds ratios are pooled estimates from multiple imputed data sets, adjusted for site. The base + R + A (full model) includes all variables listed.
b
Compared with none or not reported.