The incidence of sudden infant death syndrome in North Carolina's cities and counties: 1972--1974.

Between January 1, 1972 and December 31, 1974, 534 Sudden Infant Death Syndrome cases were reported in North Carolina. All but the out-of-state cases were mapped by county and city locations to determine if urban or rural cases predominated. The mapping was also undertaken to see if significant spatial variabilities could be detected between the county and city populations of infants at risk. The state had an overall SIDS rate of 2.06 per thousand live births. The mapping revealed that counties had a range from zero to a high of 6.6 and that cities with populations of over 10,000 had SIDS rates which ranged from zero to a high of 10.6. The proportions of SIDS cases occurring in either urban or rural locations roughly approximated the distribution of the state's population, with neither location accounting for disproportionately more cases. The larger cities, however, reported more cases than did their suburbs and the immediately surrounding rural areas. The largest and smallest cities, when grouped accordingly, had the lowest urban SIDS rates. The summary SIDS rates for whites was 1.23 per thousant live births, for blacks it was 3.75, and for Indians it was 6.56 per thousand live births.