Table 1.

Association between percentage rectal spacer use in the past and % diagnosis and related procedures around bowel, urinary, or sexual dysfunction at present

Panel A: Diagnosis
% bowel, urinary, or sexual dysfunction diagnosis at year = t (IRR)
	(1)	(2)	(3)	(4)	(5)
%Spacer adoption
At year = t-1	0.929**
	[0.869,0.994]
At year = t-2		0.855***
		[0.795,0.920]
At year = t-3			0.808***
			[0.741,0.882]
At year = t-4				0.672***
				[0.597,0.757]
At year = t-5					0.449***
					[0.377,0.535]
N	11,342	11,294	11,263	11,202	11,062

Panel B: Procedure
% procedures related to bowel, urinary, or sexual dysfunction at year = t (IRR)
	(1)	(2)	(3)	(4)	(5)
%Spacer adoption
At year = t-1	0.846**
	[0.724, 0.989]
At year = t-2		0.858
		[0.718, 1.025]
At year = t-3			0.989
			[0.822, 1.190]
At year = t-4				0.677***
				[0.539, 0.850]
At year = t-5					0.574***
					[0.397, 0.830]
N	11,342	11,294	11,263	11,202	11,062

The table shows IRR [with 95% confidence interval] based on zero-inflated Poisson regression with controls: patient characteristics at the county-level (median age, percentage white patients, percentage RT type) and characteristics of the general population (median age, % white, and median household income). “At year = t” in the outcome variable means that the outcome was measured at the present year. “At year = t-1” in the independent variable means that the spacer use rate was captured 1 year prior to the observation of the outcome; “at year = t-2” means 2 years prior etc

IRR incidence rate ratio, RT radiotherapy

**Statistically significant at < 0.05; ***statistically significant at < 0.01