Researchers in California interviewed mothers or carers of 185 infants who died and 312 randomly selected controls matched for race/ethnicity and age.
They obtained information on dummy use during the index sleep (defined as the last sleep or the sleep during the night before the interview), on other environmental factors related to sleep, and on risk factors for SIDS.
After adjusting for known risk factors, use of a dummy during sleep was associated with a 90% reduced risk of SIDS compared with infants who did not use a dummy.
The reduced risk was consistent across a wide range of social and economic characteristics and risk factors examined.
The reduced risk also seemed to be stronger when an infant was in an adverse sleep environment (such as sleeping prone or on the side, sleeping with a mother who smoked, or sleeping on soft bedding), although these differences did not reach significance.
"Use of a dummy is associated with a substantial reduction in the risk of SIDS," say the authors. "Our results also provide some evidence that use of a dummy may reduce the impact of other risk factors for SIDS, especially those related to adverse sleep conditions."
They suggest that the use of dummies may be an effective strategy for public health intervention.