Early-life risk factors for both infant colic and excessive crying without colic.

Infant colic characterized by apparent gastrointestinal distress may be phenotypically distinct from excessive crying only. Literature that defines colic only based on crying behaviors may miss important predictors. Mother-reported colic and excessive crying appear to have overlapping risk factors, with additional risk factors identified for colic. The presence of multiple risk factors increases the risk of colic, supporting a multifactorial etiology.