Table 3. Multivariate analysis of risk factors.

Outcome	Infection requiring removal					Bone resorption					Overall complications
Variable	Univariate		Multivariate			Univariate		Multivariate			Univariate		Multivariate
	OR	95% CI	OR	95% CI	p-Value	OR	95% CI	OR	95% CI	p-Value	OR	95% CI	OR	95% CI	p-Value
Age
40–60 vs. < 40	0.64	0.20–2.04	–	–	NS	0.48a	0.10–2.31	–	–	NS	0.53	0.25–1.15	–	–	NS
> 60 vs. < 40	0.42	0.05–3.40	–	–				–	–		0.93	0.32–2.67	–	–
> 60 vs. 40–60	0.66	0.07–6.33	–	–				–	–		1.74	0.52–5.78	–	–
CSF leak intraoperative
Yes vs. no	2.92	1.16–7.37	4.50	1.67–12.07	0.003	3.08	0.84–11.33	–	–	NS	2.17	1.15–4.08	2.38	1.25–4.54	0.009
CSF leak postoperative
Yes vs. no	4.1	0.36–47.27	–	–	NS	N/A		–	–	NS	N/A		–	–	NS
Interval to cranioplasty
≤ 90 vs. > 90 d	1.1	0.42–2.88	–	–	NS	1.29	0.32–5.16	–	–	NS	1.27	0.67–2.41	–	–	NS
Duration of surgery
> 2 vs. ≤ 2 hours	0.81	0.28–2.36	–	–	NS	2.65	0.73–9.55	4.18	1.09–16.03	0.037	1.16	0.59–2.26	–	–	NS
Mobility impaired
Yes vs. no	0.7	0.27–1.82	–	–	NS	0.61	0.151–2.43	–	–	NS	1.610	0.86–3.01	–	–	NS
Sex
Male vs. female	0.79	0.29–2.18	–	–	NS	3.07	0.38–24.89	–	–	NS	1.4	0.67–2.89	–	–	NS
Trauma indication
Trauma vs. nontrauma	1.31	0.42–4.11	–	–	NS	2.8	0.35–22.73	–	–	NS	1.64	0.77–3.53	–	–	NS
Extra-axial fluid collection
Yes vs. no	2.08	0.41–10.52	–	–	NS	N/A		–	–	NS	NA		–	–	NS
PEG tube in situ
No vs. yes	6.45	0.84–49.59	9.24	1.15–73.96	0.036	1.15	0.23–5.62	–	–	NS	0.76	0.37–1.55	–	–	NS
Tracheostomy in situ
Yes vs. no	0.71	0.23–2.22	–	–	NS	0.77	0.16–3.75	–	–	NS	1.59	0.80–3.18	–	–	NS
Smoker
Yes vs. no	1.66	0.60–4.62	–	–	NS	0.97	0.20–4.78	–	–	NS	0.75	0.35–1.64	–	–	NS
Site
Unilateral vs. bifrontal	0.51	0.20–1.26	–	–	NS	5.8	0.72–46.83	8.90	1.04–75.93	0.046	1.08	0.57–2.02	–	–	NS
Diabetes mellitus
Yes vs. no	1.48	0.31–7.20	–	–	NS	N/A		–	–	NS	0.34	0.07–1.57	–	–	NS

Abbreviations: CSF, cerebrospinal fluid; N/A, not applicable due to small numbers; NS, no statistical significance.

^aAge groups 40-60 and > 60 were combined for this analysis to compare two groups (< 40 vs. ≥ 40).