Evidence of developmental continuity from birth to 1 year: sleep, temperament, problem solving, and recognition memory.

Background: Research evidence is limited regarding developmentally appropriate care. Variations exits with respect to test procedure type, infant age at testing, and test relatedness.

Purpose: To assess developmental continuity using multiple developmental measures from birth to 12 months in a single cohort of term infants.

Methods: A secondary analysis, longitudinal, correlational design was used to assess developmental continuity in a single cohort of infants (n 27). Measures included: sleep, using the Motility Monitoring System (first 48 hours of life); temperament, using the Infant Characteristics Questionnaire (ICQ, 6 months) and the Revised Infant Temperament Questionnaire (RITQ, 12 months); problem-solving, using the Willatts Infant Planning Test (PS, 9 and 12 months); and the Fagan Test of Infant Intelligence (FTII, 6 and 9 months).

Results: Using Spearmen correlation, significant correlations included: (1) Sleep and ICQ: transitional sleep and "unpredictable" (r 0.455, P .017), "unadaptable" (r 0.420, P .026), and "dull" (r 0.416, P .028); (2) ICQ and FTII 6 months (r -0.512, P .008); (3) RITQ "approachability" and quiet sleep (r 0.662, P .005); (4) arousals in active sleep and PS at 9 months (r -0.528, P .016).

Implications For Practice: Given our reported continuity between early sleep and later developmental measures, sleep-wake state should be considered in caregiving and environmental control to support sleep. Parental education on facilitating sleep-wake regulation in the home environment is essential.

Implications For Research: These data support the existence of continuity between early sleep and later developmental milestones warranting a larger-scale investigation. Specific focus on development of care strategies for facilitating sleep immediately following birth is warranted.