Table 5

Mutlivariate regression of variables associated with advanced MIS practice (performance of 3 or more MIS procedures performed)^*

Variable	Coefficient estimate	SD	OR^† (95% CI)	p value^‡
Intercept	3.77	0.75		< 0.001
2007 survey administration	−2.02	0.40	0.13 (0.06–0.29)	< 0.001
Female sex	−0.48	0.37	0.62 (0.3–1.27)	0.19
Surgeon age, yr
< 35	0.53	0.53	1.70 (0.6–4.85)	0.32
46–55	0.30	0.46	1.35 (0.54–3.33)	0.52
56–65	−1.11	0.46	0.33 (0.13–0.82)	0.021
> 65	−1.88	0.85	0.15 (0.03–0.81)	0.030
> 10 years in practice	−0.31	0.42	0.73 (0.32–1.69)	0.46
No fellowship training	0.34	0.43	1.4 (0.6–3.28)	0.43
Population
< 50 000	−0.93	0.38	0.4 (0.19–0.83)	0.011
> 500 000	0.63	0.47	1.88 (0.75–4.72)	0.18
Community practice	−0.47	0.43	0.62 (0.27–1.45)	0.27
Weekly operating time (days)	0.05	0.12	1.05 (0.84–1.32)	0.67
Open technique for pneumoperitoneum	−0.38	0.34	0.68 (0.35–1.34)	0.27
Not performing MI appendectomy	−3.2	0.46	0.04 (0.02–0.1)	< 0.001

CI = confidence interval; MI = minimally invasive; MIS = minimally invasive surgery; OR = odds ratio; SD = standard deviation.
↵* Number of advanced MIS procedures performed (< 2 v. ≥ 3) compared using logistic regression, Nagelkerke R² = 0.453.
↵† OR > 1 denotes increased practice of ≥ 3 MIS procedures; OR < 1 denotes decreased practice of ≥ 3 MIS procedures.
↵‡ Wald χ² test.