Abnormal muscle tone at 6 months was a risk factor for cognitive function decline at 24 months for both Bayley-III cognitive cut-off scores: scores of 70 (adjusted odds ratio : 2.8 95% CI: 1.5–5.5) and 85 (AOR: 2.6 95% CI: 1.6–4.1). A cognitive score of <70 at 6-month CA had a positive predictive value (PPV) of 27.4% (95% confidence interval : 19.2–35.7%) for a cognitive score of <70 at 24-month CA, while the negative predictive value (NPV) was 97.3% (95% CI: 96.7–97.9%). Results: A total of 2,972 VLBW children, born with a mean weight of 1116.4 ± 257.5 g and mean gestational age of 29.0 ± 2.8 weeks, were evaluated. Cut-off scores of <70 and <85 were used to identify lower functioning groups based on the Bayley-III definition. The positive and negative predictive factors were also evaluated using logistic regression. The predictive validity of the cognitive performance at 6-month CA for the cognitive outcomes at 24-month CA was analyzed. Methods: We retrospectively evaluated VLBW children enrolled in the Taiwan Premature Infant Follow-up Network between 20 and completed the Bayley-III at CA of 6 and 24 months. Purpose: To assess the predictive validity of the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) cognitive scores at 6 months of corrected age (CA) for cognitive outcomes at 24 months of CA in very-low-birth-weight (VLBW) infants and investigate the predictors of change in cognitive outcomes. 4Premature Baby Foundation of Taiwan, Taipei, Taiwan.3Department of Medicine, MacKay Medical College, New Taipei City, Taiwan.2Department of Pediatrics, MacKay Children's Hospital, Taipei, Taiwan.1Department of Pediatrics, Hsinchu MacKay Memorial Hospital, Hsinchu, Taiwan.Tzu-Yu Liu 1,2, Jui-Hsing Chang 2,3, Chun-Chih Peng 2,3, Chyong-Hsin Hsu 2, Wai-Tim Jim 2,3, Jia-Ying Lin 2, Chia-Huei Chen 2, Sung-Tse Li 1, Hung-Yang Chang 2,3 * and on behalf of the Taiwan Premature Infant Follow-up Network 4

Bayley iii reliability and validity