DISCUSSION
This is the first study to investigate the effect of the Explorer Baby early intervention program. We examined the holistic development of premature infants, the percentage of developmental delays, and the stress level of their mothers by comparing two early intervention programs during the first year of life. There were no significant differences between the intervention and active control groups in terms of the neurodevelopment of the preterm infants and their parents’ stress levels. However, we found that the Explorer Baby program significantly improved cognitive skills with a large effect and expressive language skills with a medium effect during before and after therapy. The percentage of typical development increased at the end of therapy in both groups, and all children had typical development in the Explorer Baby group in the cognitive subfield. The NDT group showed a significant improvement in P‐CDI during 