Table 3.

ORN severity in relation to radiation modality, dose and time to diagnosis

	Stage 1	Stage 2	Stage 3	p value
Radiation modality ∞	IMRT 4/4	IMRT 3/3	IMRT 1/5	p = 0.03*
			Conventional 4/5
Radiation dose (Gy), mean ± SD §	52.5 ± 5	60 ± 0	59 ± 9.86	p = 0.312¶
Average time from radiation to diagnosis in months (range)	6.47 (3.0–12.0)	9.83 (6.0–11.9)	52.35 (9.0–129.6)	p = 0.056¶

^∞ Modality information is missing on 1 patient with Grade 1 and 1 patient with Grade 3 disease.

^§ Dose information missing in 2 patients with Grade 3 and 1 patient with Grade 1 disease.

* Freeman-Halton extension of the Fisher exact probability test.

^¶ One-way Analysis of Variance (ANOVA).

IMRT intensity modulated radiation therapy.

SD standard deviation.