Effects of the INSIGHT Obesity Preventive Intervention on Reported and Observed Infant Temperament.

The sample was predominantly White and well-educated, so the results may not apply to more diverse families. Infant temperament was not measured before the intervention began, so the study cannot show how much each infant changed from their own starting point. The observed temperament task was one laboratory situation on one day, and effect sizes for significant findings were 0.26 to 0.36, described as small to medium. The intervention combined sleep, feeding, soothing, and play guidance, so the study cannot identify which component mattered. At age 16 weeks, some intervention sessions had already occurred, so early temperament differences cannot be treated as a clean baseline. This analysis reports temperament outcomes, not the trial's obesity prevention outcomes. At age 1 year, 253 of 279 mother-infant pairs remained, with loss to follow-up and personal constraints among dropout reasons. Analyses used 240 or 230 of the 291 randomized pairs, because 1-year temperament data were missing for some participants.

Do not read these temperament differences as proof that the program will improve obesity outcomes or later development. The trial did not measure infant temperament before the intervention, the observed effects were small to medium and came from one laboratory situation, and the sample was predominantly White and well-educated.