Table 2.

Odds of receiving initial denial for proton beam therapy in adults

Characteristic	Unadjusted OR (95% CI)	P value	Adjusted OR (95% CI)	P value
Sex
Male	Reference		Reference
Female	1.64 (0.91–2.95)	.10	2.04 (0.91–4.57)	.09
Treatment site
Central nervous system	Reference		Excluded from model*
Head and neck	0.94 (0.38–2.34)	.90
Thorax	1.09 (0.50–2.37)	.83
Abdomen	1.42 (0.51–3.97)	.51
Pelvis	1.57 (0.51–4.85)	.43
Diagnosis
Low- or high-grade glioma	Reference		Reference
Non-small cell lung cancer	0.42 (0.08–2.20)	.30	0.45 (0.06–3.42)	.44
Breast cancer	1.54 (0.53–4.51)	.43	0.99 (0.20–4.98)	.99
Primary liver cancer	1.52 (0.39–5.91)	.54	3.12 (0.66–14.74)	.15
Prostate cancer	2.77 (0.47–16.21)	.26	2.17 (0.27–17.56)	.47
Sarcoma	0.46 (0.12–1.76)	.26	0.63 (0.14–2.87)	.55
Lymphoma	2.31 (0.49–10.82)	.29	3.04 (0.38–24.59)	.30
Benign histology	0.97 (0.30–3.14)	.96	0.96 (0.26–3.55)	.95
Other	1.58 (0.55–4.55)	.40	2.46 (0.67–9.12)	.18
ASTRO PBT Model Policy
Group 1	Reference		Reference
Group 2	2.74 (1.05–7.16)	.039‡	2.44 (0.43–13.84)	.31
Other	1.10 (0.53–2.28)	.81	1.04 (0.28–3.94)	.95
Reirradiation setting
Yes	Reference		Reference
No	1.45 (0.75–2.87)	.26	1.46 (0.52–4.14)	.47
Clinical trial enrollment
Yes	Reference		Reference
No	0.99 (0.32–3.06)	.98	2.81 (0.53–15.04)	.23
Insurance category
Commercial/managed care	Reference		Reference
Medicare	†		†
Medicaid	0.20 (0.10–0.41)	<.001‡	0.17 (0.08–0.39)	<.001‡
Military	0.05 (0.002–1.57)	.09	0.03 (0.0004–1.38)	.07
Charity care	†		†

Abbreviations: ASTRO = American Society for Radiation Oncology; CI = confidence interval; OR = odds ratio; PBT = proton beam therapy.

^*Treatment site variable excluded from multivariable analysis because of multicollinearity with diagnosis category.

^†Prior authorization not required.

^‡Statistically significant.