PURPOSE: Motor, cognitive, behavioral, and sensory problems may be seen in preterm infants. Early spontaneous movements' role in these developmental areas has yet to be sufficiently investigated. This study aimed to evaluate the effectiveness of the Motor Optimality Score-Revised (MOS-R) in predicting motor, cognitive, language, and sensory developmental outcomes in premature infants. METHODS: Forty preterm children were examined. Early spontaneous movements were evaluated using the General Movement Assessment (GMA), which detects the MOS-R. Infants' language, cognitive, and motor development were assessed using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III). Sensory development was evaluated using the Test of Sensory Functions in Infants (TSFI). RESULTS: The mean score for the MOS-R was 23.13 ± 4.6. Most infants (n = 31, 77.5%) showed typical fidgety movements. The sensitivity of the MOS-R for determining motor, cognitive, and language development at 12 corrected months was 86.7%, 80%, and 82%, respectively, and the specificity was 71.4%, 100%, and 100%, respectively. MOS-R scores did not predict sensory development outcomes (p >
0.05) CONCLUSIONS: At three months, the MOS-R demonstrated high sensitivity and specificity in detecting motor, cognitive, and language functions in preterm infants at 12 months corrected age.