Development and validation of the infant feeding intentions scale

Abstract

Objectives: There is a need in breastfeeding behavior studies for a quantitative measure of maternal breastfeeding intentions. The Infant Feeding Intentions (IFI) scale was developed to fill this need.

Methods: Two items probe strength of intentions to initiate breastfeeding and subsequent items assess strength of intentions to be breastfeeding exclusively (EBF) at 1, 3, or 6 months. Total score ranges from 0 to 16. Content validity was established among women in their third trimester of pregnancy (n = 88). Subsequently, construct validity was assessed in a low-income, multi-ethnic cohort of primiparae (n = 170) interviewed at 25 +/- 15 h postpartum and followed to 6 months.

Results: Cronbach's coefficient alpha was 0.90 for both the content and construct validity samples. Construct validity was demonstrated by a significant association between IFI score and both planned and actual EBF duration: mean (+standard deviation) IFI scores were 4.6 +/- 2.9, 7.5 +/- 3.2, 10.3 +/- 2.7, 12.0 +/- 1.8, and 13.8 +/- 2.7 for planned duration of EBF of 'Never', up to 1 month, 1 to <3 months, 3 to <6 months, and > or =6 months, respectively; ANOVA, P < 0.0001; and each 1-point increase in IFI score decreased the hazard of not EBF by 23.4% at day 0 and 13.7% at day 30 (Cox proportional hazards model chi-square = 92.5, P < 0.0001).

Conclusions: In a multi-ethnic U.S. sample of low-income primiparae, the IFI scale was shown to be a valid, simple tool for quantitatively assessing the strength of intentions to initiate and sustain EBF.