Assessment of Abbreviated Techniques for Determination of Milk Volume Intake of the Human Milk-Fed Infant

Summary: Two recently proposed abbreviated techniques for estimation of 24-h milk intake of the breast-fed infant were evaluated as to whether they could serve as appropriate substitutes for measured 24-h intakes. One technique involves the doubling of 12-h milk intakes, whereas the other uses the product of the mean of two consecutive midpoint feedings and the frequency of nursing for the defined 24-h period. Data from three consecutive 24-h intake measurements at 4, 8, and 12 weeks on 22 solely breast-fed infants were used for the evaluation. Correlational and paired t test analyses were conducted to compare intakes from each abbreviated technique with measured intakes. All calculated intakes derived from doubling 12-h periods commencing in the morning exceeded values obtained for full-day measures. These overestimations resulted from higher milk consumption during the early hours of the day, with proportionate intakes ranging from 0.55 to 0.77. Doubled half-day calculations initiated later in the day (2 p.m.-2 a.m.) were similar to mean measured 24-h intakes, with proportionate intakes ranging from 0.47 to 0.51. Correlations between all calculated intakes and measured intakes ranged from 0.51 (p = 0.111) to 0.93 (p = 0.001). Estimated mean intakes derived by the method utilizing nursing frequency and the mean for two nursings were similar to measured 24-h mean intakes. Correlations between such 24-h calculated and measured intakes ranged from 0.70 (p = 0.001) to 0.97 (p < 0.001). Results indicate that doubled half-day measures involving the 2 p.m.-2 a.m. time frame and estimated intakes calculated from nursing frequency and the mean for two nursings may be appropriate approaches for population studies. However, such abbreviated techniques cannot be supported as substitutes for measured 24-h intakes for individual infants.