TABLE 1.

Descriptions of psychosocial factors used in analyses¹

Psychosocial factor	Description
Social knowledge of breastfeeding	None; 1 or 2; 3–5; or >5 of mother's friends or relatives had breastfed. None included no friends or relatives had breastfed, no friends or relatives had children, or mother did not know.
Social influence toward breastfeeding	Low, medium, and high tertiles of a range of scores on the basis of infant-feeding opinions (and their importance to the mother) of the infant's father, the mother's mother, her mother-in-law, her obstetrician, and the infant's pediatrician.
Attitudes and behavioral beliefs about breastfeeding	Low, medium, and high tertiles of a range of scores on the basis of the quality of the mother's opinion of the best infant-feeding method in the first few weeks postpartum and the quality of her beliefs about breastfeeding.
Maternal confidence in breastfeeding	Low, medium, and high on the basis of a 5-point scale on which a mother ranked how confident she was that she would breastfeed as long as her prenatal breastfeeding goal.

¹See Supplemental Table 1 under “Supplemental data” in the online issue for more-detailed descriptions of these variables.