Table 4

Multiple linear regression model relating waiting times between last chemotherapy or surgery or biopsy and first radiation therapy (RT) to patients’ characteristics among patients with breast cancer in Ontario (n = 1264)^*

Characteristic	Patients with chemotherapy^† (n = 579)		Patients without chemotherapy^‡ (n = 685)
Characteristic	β	p value^§	β	p value^§
Constant	33.77	< 0.001	11.50	< 0.001
Age per 10 yr	−0.61	0.05	0.49	0.005
Central-East HR (yes v. other regions)	−1.64	0.15	−1.32	0.12
Central-South HR (yes v. other regions)	−1.31	0.34	1.75	0.030
Central-West HR (yes v. other regions)	−3.62	0.001	1.61	0.032
East HR (yes v. other regions)	−1.60	0.14	−3.30	< 0.001
North HR (yes v. other regions)	−2.91	0.011	−4.76	< 0.001
South-West HR (yes v. other regions)	2.10	0.07	−0.98	0.18
Stage I (yes v. other stages)	−5.10	< 0.001	−1.09	0.012
Model R²^¶	0.13		0.18

↵* 7 patients with missing data were excluded.
↵† Time from last chemotherapy to first RT.
↵‡ Time from surgery or biopsy to first RT.
↵§ Significance was set at p < 0.05.
↵¶ Adjusted for comorbidity and socioeconomic status.