Ingrid Kvestad1, Mari Hysing2, Suman Ranjitkar3, Merina Shrestha3, Manjeswori Ulak4, Ram K Chandyo5, Tor A Strand6. 1. Regional Centre for Child and Youth Mental Health and Child Welfare, NORCE Norwegian Research Centre, Bergen, Norway; Department of Research, Innlandet Hospital Trust, Lillehammer, Norway. Electronic address: inkv@norceresearch.no. 2. Department of Psychosocial Science, Faculty of Psychology, University of Bergen, Bergen, Norway. 3. Department of Child Health, Institute of Medicine, Tribhuvan University, Kathmandu, Nepal. 4. Department of Child Health, Institute of Medicine, Tribhuvan University, Kathmandu, Nepal; Centre for Intervention Science in Maternal and Child Health, Centre for International Health, Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway. 5. Department of Community Medicine, Kathmandu Medical College, Kathmandu, Nepal. 6. Department of Research, Innlandet Hospital Trust, Lillehammer, Norway.
Abstract
BACKGROUND: The Bayley Scales of Infant and Toddler Development is widely used worldwide. The objective of the current study was to measure the stability of the Bayley Scales during early childhood and its relationship with intellectual abilities at four years in young Nepalese children. METHODS: In a prospective cohort we used the Bayley 3rd edition to measure early child development in 529 Nepalese children at 6-11, 18-23 and 30-35 months. At four years, we used the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) to measure intellectual abilities. We expressed the stability of the Bayley scores by intraclass correlation coefficients (ICCs) and concordance correlation coefficients (CCCs). The relationship between the Bayley scores and the WPPSI full-scale IQ (FSIQ) at four years was examined in regression models. RESULTS: The ICCs between the Bayley scores across timepoints were 0.01 (95 % CI -0.06, 0.04), 0.19 (95 % CI 0.15, 0.26) and 0.22 (95 % CI 0.17, 0.28) for the Cognitive, Language and Motor composite scores. The CCC for the composite scores ranged from 0.05 to 0.20 between 6 and 11 and 30-35 months and from 0.20 to 0.36 between 18 and 23 and 30-35 months. The Bayley scores at 6-11, 18-23 and 30-35 months explained 3 %, 20 % and 36 % of the variation of the FSIQ. CONCLUSION: The stability of the Bayley scales is poor in early childhood, and its relationship with future intellectual abilities is poor in infancy but improves slightly with age in early childhood. Findings from this large community-based cohort of healthy at-risk children are relevant when measuring early child development worldwide.
BACKGROUND: The Bayley Scales of Infant and Toddler Development is widely used worldwide. The objective of the current study was to measure the stability of the Bayley Scales during early childhood and its relationship with intellectual abilities at four years in young Nepalese children. METHODS: In a prospective cohort we used the Bayley 3rd edition to measure early child development in 529 Nepalese children at 6-11, 18-23 and 30-35 months. At four years, we used the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) to measure intellectual abilities. We expressed the stability of the Bayley scores by intraclass correlation coefficients (ICCs) and concordance correlation coefficients (CCCs). The relationship between the Bayley scores and the WPPSI full-scale IQ (FSIQ) at four years was examined in regression models. RESULTS: The ICCs between the Bayley scores across timepoints were 0.01 (95 % CI -0.06, 0.04), 0.19 (95 % CI 0.15, 0.26) and 0.22 (95 % CI 0.17, 0.28) for the Cognitive, Language and Motor composite scores. The CCC for the composite scores ranged from 0.05 to 0.20 between 6 and 11 and 30-35 months and from 0.20 to 0.36 between 18 and 23 and 30-35 months. The Bayley scores at 6-11, 18-23 and 30-35 months explained 3 %, 20 % and 36 % of the variation of the FSIQ. CONCLUSION: The stability of the Bayley scales is poor in early childhood, and its relationship with future intellectual abilities is poor in infancy but improves slightly with age in early childhood. Findings from this large community-based cohort of healthy at-risk children are relevant when measuring early child development worldwide.