During the Chicago debate between third-party presidential candidates, Justice Party candidate Rocky Anderson said that the U.S. has the highest infant mortality rate among developed nations. 

Anderson appears to be referring to a report from the Congressional Research Service, which said that the U.S. ranks 31st out of 34 nations belonging to the Organization for Economic Cooperation and Development. Only Chile, Mexico and Turkey ranked lower than the U.S. in terms of infant-mortality rate. (See page 5 of the report). 

Interestingly, the U.S. ranks higher in healthcare spending than some of the nations that have a lower infant-mortality rate, suggesting that the U.S. is seeing rather poor outcomes for its money.