Twelve months infants with cystic fibrosis will be assessed by the Bayley-III Baby and Child Development Assessment Scale (Bayley III) and the Rough Motor Function Measure.

Twelve months healthy infants will be assessed by the Bayley-III Baby and Child Development Assessment Scale (Bayley III) and the Rough Motor Function Measure.

Infants' neurodevelopmental assessments will be done by the Bayley-III Baby and Child Development Assessment Scale (Bayley III) and the Gross Motor Function Measure. Bayley-III assess the development of five distinct scales to be consistent with areas of appropriate developmental assessment for children from birth to age 3. The Bayley-III revision includes Cognitive, Language, Motor, Social-Emotional, and Adaptive Behavior scales.The Gross Motor Function Measure (GMFM) has 5 dimensions: A-lying and roll- ing; B-sitting; C- kneeling and crawl- ing; D-standing; and E-walking, run- ning, and jumping. The items are scored from 0 to 3. All items are summarized and expressed as a value of total points for each dimension of the GMFM.

It consists of a total of 88 items in the supine-posed position and during rotation, 17 items in sitting, 20 items in sitting, 14 items in crawling and kneeling, 13 items during standing, 24 items during walking-running-jumping. The child is scored according to the degree of achievement of gross motor functions in these materials. If the child can not initiate the activity 0 is given, can initiate independently 1 is given, can partially complete 2 is given, can independently complete 3 is given.

The Bayley-III includes Cognitive, Language, Motor, Social-Emotional, and Adaptive Behavior scales.

Cognitive. The Cognitive scale of the Bayley-III contains 91 items. Language. This subtest contains 48 items. The Expressive Communication subtest assesses the individual's ability to vocalize, name pictures and objects, and communicate with others.

Motor. The Bayley-III Motor scale include Fine Motor and Gross Motor subtests. The Fine Motor subtest contains 66 items and is purported to measure skills associated with eye movements, perceptual-motor integration, motor planning, and motor speed. The Gross Motor subtest contains 72 items and is designed to measure movements of the limbs and torso.

Social-Emotional. This scale include 35 items, which measure emotional development and related behaviors.

Adaptive Behavior. Bayley-III include the Adaptive Behavior Assessment System-Second Edition as a measure of adaptive skills.