Exhibit 2.

Unadjusted and adjusted risk difference (RD) for severe maternal morbidity (SMM) in New York City in 2012–14, by racial and economic spatial polarization measures

		Unadjusted RD		Adjusted RDa
ICE measure	Cases per 100	Cases per 100	95% CI	Cases per 100	95% CI
ICE Race
Quintile 1	4.1	2.4	2.0, 2.8	0.3	0.1, 0.6
Quintile 2	2.8	1.0	0.7, 1.3	0.1	−0.1, 0.3
Quintile 3	2.1	0.4	0.0, 0.7	0.2	−0.1, 0.4
Quintile 4	1.7	0.0	−0.3, 0.3	0.0	−0.2, 0.4
Quintile 5	1.7	0.0	Ref	0.0	Ref
ICE Income
Quintile 1	3.1	1.4	0.8, 2.0	0.4	0.2, 0.6
Quintile 2	2.7	1.0	0.6, 1.5	0.4	0.2, 0.6
Quintile 3	2.4	0.7	0.3, 1.2	0.3	0.1, 0.5
Quintile 4	2.1	0.5	0.2, 0.8	0.3	0.1, 0.5
Quintile 5	1.7	0.0	Ref	0.0	Ref
ICE Race−Income
Quintile 1	4.0	2.3	1.9, 2.7	0.4	0.2, 0.6
Quintile 2	2.5	0.8	0.5, 1.1	0.2	0.0, 0.4
Quintile 3	2.0	0.3	0.0, 0.7	0.2	0.0, 0.5
Quintile 4	1.8	0.2	−0.1, 0.4	0.2	0.0, 0.4
Quintile 5	1.7	0.0	Ref	0.0	Ref

SOURCE Authors’ analysis of New York City birth certificate and hospital discharge data linked to American Community Survey data.

NOTES N = 316,600. The Index of Concentration at the Extremes (ICE) measures for race, income, and race and income are explained in the notes to exhibit 1. Quintile 1 represents the highest relative concentration of non-Hispanic black, low-income, or non-Hispanic black and low-income households, and quintile 5 the lowest. CI is confidence interval.

^aAdjusted for race/ethnicity, age, nativity, previous live births, education, insurance status, prepregnancy body mass index, multiple pregnancy, prepregnancy diabetes, prepregnancy hypertension, gestational diabetes, gestational hypertension, cardiac disease, renal disease, pulmonary disease, musculoskeletal disease, blood disorders, mental disorders, central nervous system disorders, rheumatic heart disease, placentation disorders, anemia, asthma, prior cesarean delivery, and hospital of delivery.