Table 1: Estimated regression coefficients (standard errors) for a generalized linear model applied to administrative health data for combinations of study duration and frequency of outcome measurements per year; model contained coefficients to estimate the quadratic trend over time.

Note: Bold values are statistically significant at α=0.05

Duration (years)	Freq	Estimated Regression Coefficients (Standard Errors)
		Group	Time	Time-Time	Group-Time	Group-Time-Time
1	3	2.39 (0.61)	-2.73 (0.27)	0.59 (0.07)	-0.76 (0.67)	0.35 (0.16)
	4	1.98 (0.36)	-1.67 (0.12)	0.29 (0.02)	-0.70 (0.30)	0.22 (0.06)
2	2	0.13 (0.62)	-1.28 (0.21)	0.27 (0.04)	3.77 (0.56)	-0.84 (0.11)
	3	0.98 (0.34)	-0.61 (0.08)	0.09 (0.01)	1.18 (0.22)	-0.19 (0.03)
	4	0.80 (0.24)	-0.38 (0.04)	0.04 (<0.00)	0.66 (0.11)	-0.08 (0.01)
3	1	9.76 (1.55)	0.20 (0.64)	0.10 (0.16)	-2.28 (1.66)	0.10 (0.41)
	2	3.71 (0.46)	-0.20 (0.11)	0.04 (0.02)	0.03 (0.26)	-0.06 (0.04)
	3	2.42 (0.28)	-0.12 (0.04)	0.02 (0.00)	0.03 (0.11)	-0.02 (0.01)
	4	1.80 (0.20)	-0.08 (0.02)	0.01 (0.00)	0.02 (0.06)	-0.01 (0.00)
4	1	11.04 (1.09)	1.86 (0.38)	-0.34 (0.08)	-3.90 (0.86)	0.52 (0.17)
	2	4.62 (0.41)	0.28 (0.07)	-0.03 (0.01)	-0.71 (0.16)	0.04 (0.02)
	3	2.94 (0.26)	0.10 (0.03)	-0.01 (<0.00)	-0.28 (0.07)	0.01 (<0.00)
	4	2.16 (0.19)	0.05 (0.02)	<0.00 (<0.00)	-0.15 (0.04)	<0.00 (<0.00)