Table 4.

Change in the proportion of facilities meeting specific benchmarks pertaining to patient tracking in the Chicago Breast Cancer Quality Consortium (2006-2013).

Number of time points available for analysis	Not Lost at imaging			Not Lost at biopsy			Known minimal status			Known stage at diagnosis
	Na	%b	Pd	Na	%b	Pd	Na	%b	Pc	Na	%b	Pc
2 time points
1	53	70		53	74		56	46		56	46
2	53	77		53	75		56	48		56	46
3 time points						0.16
1	20	55		20	70		23	57		23	48
2	20	55		20	70		23	57		23	52
3	20	60		20	85		23	61		23	61
4 time points									0.06
1	16	50		16	69		34	38		34	38
2	16	63		16	81		34	65		34	82
3	16	56		16	88		34	59		34	50
4	16	56		16	81		34	62		34	41
5 time points						0.02
1	25	76		25	60
2	25	88		25	88
3	25	96		25	92
4	25	96		25	92
5	25	72		25	80
Combined						0.003			0.04
1	114	66		114	69		113	46		113	44
2	114	74		114	78		113	55		113	58
3	61	74		61	89		57	60		57	54
4	41	80		41	88		34	62		34	41
5	25	72		25	80

^aNumber of facilities with data at specified time points.

^bPercentage of facilities meeting the benchmark at each time point.

^cP-values from a Wald test for trend in logistic regression with generalized estimating equations to account for clustering by facility. All P-values >0.20 are suppressed. Data on known minimal status and known stage were not collected for CY 2006, therefore no facilities have 5 time points available on these benchmarks.