Table 3.

Associations of country and place with breast cancer care delays: relatively poor compared with affluent neighborhoods, and extremely poor compared with extremely affluent neighborhoods.

Cancer care indicator	California				Ontario				Ontario/California
Neighborhood	n	Rate^a (Mdn)	RR^b	95% CI^c	n	Rate^a (Mdn)	RR^b	95% CI^c	MDD	RR	95% CI^c
Waited 60 days or longer for initial surgery
Extremely affluent	47	0.013 (3)	1.00	…	50	0.072 (8)	1.00	…	5	5.53	1.00, 30.58^d
Affluent	90	0.045 (5)	1.00	…	100	0.101 (13)	1.00	…	8^*	2.24	0.75, 6.71
Poor	94	0.100 (10)	2.22	0.77, 6.41	99	0.081 (13)	0.80	0.33, 1.95	3	0.81	0.40, 1.63
Extremely poor	47	0.157 (11)^*	12.08	1.65, 88.66	49	0.065 (9)	0.90	0.53, 1.52	32	0.41	0.17, 0.99^d
Received lumpectomy and waited 90 days or longer for radiation therapy
Extremely affluent	24	0.375 (68)	1.00	…	20	0.700 (97)	1.00	…	29	1.87	1.05, 3.33
Affluent	42	0.405 (89)	1.00	…	41	0.699 (110)	1.00	…	21^*	1.73	1.15, 2.60
Poor	35	0.584 (105)	1.44	1.01, 2.05^d	56	0.573 (110)	0.82	0.62, 1.09	5	0.98	0.41, 2.34
Extremely poor	17	0.785 (111)^*	2.09	1.17, 3.74	27	0.556 (95)	0.79	0.50, 1.24	316	0.71	0.51, 0.99^d

Notes: Within-country comparisons were of the poor versus the affluent and of the extremely poor versus the extremely affluent. n=number of incident breast cancer cases, Mdn=median days waited, RR=standardized rate ratio, CI=confidence interval, MDD=median days difference. Bolded RRs and CIs are statistically significant.

All rates were directly age-adjusted using this study’s combined Ontario-California population of cases as the standard (age strata: 25–44, 45–54, 55–64, 65–74 and 75 years or older), so all of the rates for each cancer care indicator are directly comparable.

A survival rate ratio of 1.00 is the within-country baseline.

Confidence intervals are based on the Mantel–Haenszel χ²-test.

90% confidence interval.

Median wait differed significantly from baseline (within-country) or between-countries: Mann–Whitney U-test, P<0.05.