borderline significantP =0.05
There was borderline significant heterogeneity by age of the association of ethnicity with ER status ( P =0.05) such that in patients aged under 60, the black patients were significantly more likely to have ER-negative disease (OR=2.36, 95% CI 1.06–5.00, P =0.03), but there was no significant difference in ER status by ethnicity in patients aged 60 years or above (OR=0.71, 95% CI 0.23–2.18, P =0.5).