Table 1

Characteristics of the study population by cause of death category

CharacteristicTotal (n=778)Unexplained* (n=276)Unintentional asphyxia (n=502)
Age (n, %)
 Less than 2 months232 (29.8)86 (31.2)146 (29.1)
 2–4 months369 (47.4)130 (47.1)239 (47.6)
 5–11 months177 (22.8)60 (21.7)117 (23.3)
Race/ethnicity (n, %)
 White, non-Hispanic269 (34.6)93 (33.7)176 (35.1)
 Black, non-Hispanic299 (38.4)104 (37.7)195 (38.8)
 Hispanic135 (17.4)49 (17.8)86 (17.1)
 Other, non-Hispanic55 (7.1)23 (8.3)32 (6.4)
 Unknown20 (2.6)7 (2.5)13 (2.6)
Sex (n, %)
 Male458 (58.9)145 (52.5)313 (62.4)
 Female320 (41.1)131 (47.5)189 (37.7)
Gestational age in weeks (n, %)
 ≥37593 (76.2)206 (74.6)387 (77.1)
 <37155 (19.9)58 (21.0)97 (19.3)
 Unknown1 (0.1)1 (0.4)0 (0)
 Missing29 (3.7)11 (4.0)18 (3.6)
Birth weight in grams (n, %)
 ≥2500629 (80.9)219 (79.4)410 (81.7)
 <2500149 (19.2)57 (20.7)92 (18.3)
Maternal age (n, %)
 <2086 (11.1)25 (9.1)61 (12.2)
 20–25320 (41.1)113 (40.9)207 (41.2)
 26–35293 (37.7)104 (37.7)189 (37.7)
 >3550 (6.4)23 (8.3)27 (5.4)
 Missing29 (3.7)11 (4.0)18 (3.6)
Maternal education level (n, %)
 Less than high school189 (24.3)68 (24.6)121 (24.1)
 High school graduate318 (40.9)97 (35.1)221 (44.0)
 Some college186 (23.9)80 (29.0)106 (21.1)
 College graduate45 (5.8)16 (5.8)29 (5.8)
 Unknown11 (1.4)4 (1.5)7 (1.4)
 Missing29 (3.7)11 (4.0)18 (3.6)
  • *Includes cases with undetermined, unknown, sudden infant death syndrome (SIDS) and sudden unexpected infant death (SUID) as the underlying cause documented on the death certificate.