Gender differences in cognitive abilities at 2 years in ELBW infants. Extremely low birth weight

Gender differences in cognitive abilities exist for children born at term. For very preterm infants uncertainty exists regarding the presence and extent of such differences and their relationship to perinatal brain injury and neurological impairment. This study examined gender differences in cognitive abilities in a cohort of 336 extremely low birth weight (ELBW) infants at 2 years corrected age. Infants were classified as at low or high perinatal risk at birth according to four perinatal risk factors. A subgroup of 33 neurologically impaired infants was identified. Outcome at 2 years was measured by the overall General Quotient (GQ) on the Griffiths scale and its five subscale scores. Female ELBW children were superior to male ELBW children by 4.1 GQ points (95% CI 1.0, 7.1). If the impaired subgroup was excluded, the difference in GQ was 3.2 points (95% CI 0.4, 5.6), and this difference was predominantly due to female infants being superior in the hearing and speech subscale (6.0 points, 95% CI 2.6, 9.5). These differences were relatively independent of perinatal risk status. Gender differences in the Griffiths GQ for ELBW infants are similar to expected differences for term infants and are unlikely to cause substantial bias in interpreting outcome studies for ELBW infants, unless these involve tests of specific cognitive abilities such as language.     

Neurologic status and intracranial hemorrhage in very-low-birth-weight preterm infants. Outcome at 1 year and 5 years

Twenty-six very-low-birth-weight preterm infants with and without intracranial hemorrhage (ICH) were followed up prospectively from birth to school age to determine the relationship between ICH and subsequent neurologic and cognitive outcomes. All children had sequential cranial ultrasound examinations at birth and neurologic assessments at 3-month intervals during the first year, at 1 year of age, and at 5 to 6 years; psychometric assessments were done at 5 to 6 years. Seventeen children had no ICH, 3 had grade 1 ICH, 1 had grade 3 ICH, and 5 had grade 4 ICH. The 1-year Amiel-Tison neurologic assessment in 25 infants demonstrated that 14 were normal, 3 were suspect, and 8 were abnormal. By 5 to 6 years of age, 5 of 8 children neurologically abnormal at 1 year remained abnormal, 2 of 3 children neurologically suspect at 1 year remained suspect; while 9 of 15 children neurologically normal at 1 year remained normal, the remaining 6 had become suspect. The predominant neurologic abnormality at 5 to 6 years was subtle neurologic dysfunctioning. The Wechsler Preschool and Primary Scale of Intelligence at 5 to 6 years revealed a mean group IQ score of 92.1. The Beery Visual Motor Integration Test results demonstrated that 18 of 26 children had mild to severe visual motor perceptual difficulties. Severe ICH (grades 3 and 4) correlated with abnormal neurologic performances at 1 and 5 to 6 years. Mild ICH (grade 1) and no ICH did not correlate with any one of the 1-year neurologic classifications. The 1-year status correlated with the 5- to 6-year neurologic outcome best for children who were either neurologically suspect or abnormal at age 1 year. The 1-year neurologic score did not correlate with 5- to 6-year IQ and Beery Visual Motor Integration Test scores.     

The influence of growth on development outcome in extremely low birthweight infants at 2 years of age

OBJECTIVE: To determine if weight < 3rd and < 10th centile at 2 years in extremely low birthweight (ELBW) infants is associated with problems of development and motor skills, and whether this association is explained by perinatal risk status. METHODOLOGY: One hundred and ninety-eight of 226 (88%) surviving ELBW infants born between January 1987 and December 1992 were assessed at 2 years corrected age. Children were classified as being at low perinatal risk (n = 128) or high perinatal risk (n = 70) for adverse developmental outcome based on perinatal risk factors. Weight at 2 years was classified as < 3rd, 3rd-9th or > or = 10th centile for age and gender. Development was assessed using the Griffiths Mental Developmental Scales and motor skills using the Neurosensory Motor Developmental Assessment (NSMDA). RESULTS: For the total study group weight centile was strongly related to General Quotient (GQ) and motor abilities. For children < 3rd percentile (n = 48) mean (GQ) was 90.4 (SD, 15.9), for children between the 3rd-9th percentile (n = 49) 91.5 (SD, 17.9), and for children > or = 10th percentile (n = 99) mean GQ was 99.8 (SD, 8.6). The association with mean GQ and NSMDA category occurred for the high-risk subgroup and became non-significant in the low-risk subgroup if neurologically abnormal children were excluded. Other perinatal risk factors, exposure to breast milk, level of maternal education, marital status and history of feeding problems or infections over the 2 years did not confound this association. CONCLUSION: Low weight percentile at 2 years was related to adverse developmental outcome in ELBW infants at high perinatal risk or with neurological impairment, though minimal association was present for neurologically normal infants at low perinatal risk.     

Cognitive abilities and school performance of extremely low birth weight children and matched term control children at age 8 years: a regional study

The intellectual, psychoeducational, and functional status of a regional cohort of extremely low birth weight (ELBW) survivors who weighed 501 to 1000 gm at birth (n = 143) and who were born between 1977 and 1981 was compared with that of control children born at term (n = 145) who were matched for gender, age, and social class. One hundred twenty-nine ELBW survivors (90%) were available; their mean birth weight was 839 +/- 124 gm and mean gestational age 27 +/- 2.1 weeks, and 48 of them weighed less than or equal to 800 gm at birth. Both ELBW and control groups were tested at a mean unadjusted age of 8 years; 113 of 129 ELBW children completed the full test battery, eight blind children had other tests, and eight were not testable. The mean Full Scale IQ (Wechsler Intelligence Scale for Children--Revised) was 91 +/- 16 for ELBW children and 104 +/- 12 for control children (p less than 0.0001). Between 8% and 12% of the ELBW group scored in the "abnormal" range (less than or equal to -2 SD) on the Wechsler IQ and subtests, compared with 1% to 2% of the control group. The ELBW group did less well on the reading, spelling, and mathematics tests (Wide Range Achievement Test--Revised less than or equal to -2 SD: ELBW = 20% to 28%; control = 3% to 10%). The motor performance of the ELBW group (Bruininks-Oseretsky Test of Motor Proficiency less than or equal to -2 SD: ELBW = 20%; control = 1%) and their visual-motor integration (Beery Developmental Test of Visual-Motor Integration less than or equal to -2 SD: ELBW = 21%; control = 6%) were also poorer. Exclusion of 19 ELBW children with neurologic impairments or an IQ less than or equal to 70 or both did not result in significant improvement in Wechsler or achievement measures. Approximately 15% of the ELBW cohort performed in the abnormal range on the Vineland Adaptive Behavior Scales, compared with none of the control group. Although approximately two thirds of the ELBW group were performing in the normal range on intellectual measures, comparison with the control group suggests that, as a group, ELBW children were significantly disadvantaged on every measure tested.     

Cognitive and educational outcomes in early adulthood for infants weighing 1000 grams or less at birth

AIM: To assess the intelligence quotient (IQ) and academic achievement in early adulthood of a cohort of extremely-low-birthweight (ELBW 1000 g) subjects. METHODS: All 82 ELBW survivors consecutively born in or referred to a single tertiary center in 1976-1981 were traced at a mean age of 18 y. Three disabled children had died. Fifty-nine subjects (75%) had their IQ tested and 69 (87%) responded to a questionnaire. They were compared to 44 term, normal birthweight (NBW) matched controls. Outcome measures were: IQ (Wechsler Adult Intelligence Scale) and educational outcome. The main outcome variables were compared between groups and analyzed for neonatal and demographic data and in the ELBW group for childhood data. RESULTS: There was a strong relationship (r2=0.55, p<0.0001) between childhood and adult IQ for the 41 ELBW subjects tested at both ages (6.1+/-1.3 and 18.4+/-1.9 y). Differences were significant between ELBW and NBW groups: in mean full-scale IQ (94+/-12 vs 108+/-14), verbal IQ (93+/-12 vs 106+/-14) and performance IQ (97+/-14 vs 109+/-16) (p<0.0001). Differences between ELBW and NBW groups in prevalence of IQ<85 (19 vs 2%, p=0.012), of schooling in a regular curriculum for age (36 vs 68%, p=0.0011), of requirement for special classes or schools (33 vs 9%, p=0.0032), and of obtainment of secondary school diploma for those 18 y or older (56 vs 85%, p=0.018) were largely due to fathers' socio-economic score. CONCLUSION: ELBW subjects had a mean adult IQ in the normal range; however, it was one standard deviation below that of NBW subjects and they had more school failures. Despite this, more than half of ELBW subjects aged 18 y or more had obtained their secondary school diploma.     

Non-anaemic iron deficiency identified by ZPP test in extremely premature infants: prevalence,dietary risk factors,and association with neurodevelopmental problems

Introduction: The aims of this study were to determine, in a cohort of extremely premature infants, the prevalence of iron deficiency identified by zinc protoporphyrin/heme ratio (ZPP) testing, and its association with neurodevelopmental problems and dietary risk factors for iron deficiency. Methods: Infants of less than 29 weeks' gestation or less than 1000 g birth weight were studied prospectively at a multidisciplinary follow-up clinic. Assessments were made at a corrected age of either 12 months (n=72) or 2 years (n=69). Physical examination, Griffiths Developmental Scale, and neurosensory-motor assessment were administered, information on diet and behaviour was obtained by questionnaire, and a fingerprick ZPP ratio was performed to identify iron deficiency. Results: 18.4% of infants had positive ZPP tests. There was no significant association between a positive ZPP test result and dietary risk factors, or symptoms of lethargy, irritability or poor attention. In children without cerebral palsy, there was no difference on Griffiths scores or neurosensory-motor assessment between ZPP-positive and ZPP-negative groups. The diagnosis of cerebral palsy (n=12) was significantly associated with both a positive ZPP test and a lower Griffiths general quotient (GQ) score. Conclusions: Iron deficiency occurs commonly in extremely low birth weight (ELBW) children in early childhood, and is not predicted by dietary risk factors. The prevalence of iron deficiency is increased in ELBW children with cerebral palsy. Non-anaemic iron deficiency (NAID) does not impair development or significantly affect behaviour of ELBW subjects who do not have cerebral palsy.     

Extremely low birthweight infants at 3 years: A developmental profile

This study documents the neurodevelopmental outcome at 3 years of 52 of 55 extremely low birthweight (ELBW) survivors (survival rate 49%) born in a tertiary maternity centre from July 1985 through December 1988, and examines more closely the developmental profile of the neurologically normal survivors. At 3 years, 6 (12%) children had severe neurodevelopmental impairment (severe cerebral palsy, blindness, deafness or a General Quotient (GQ)<70 on the Griffiths Scales), 11 (21 %) had mild to moderate impairment and 35 (67%) had no neurosensory impairment and normal development (GQ≥ 85). Significant risk factors for severe impairment were stage 3 or 4 retinopathy of prematurity (odds ratio [OR] 21.5), treatment with postnatal steroids (OR 21), grade III or IV intraventricular haemorrhage (OR 11) and supplemental oxygen at 'term'(OR 6.4). The developmental profile of the 35 neurologically normal children revealed a significant weakness in eye and hand coordination skills and a relative strength in hearing and speech skills. Early recognition of this developmental profile may allow implementation of more appropriate preschool programmes for ELBW children.     

Selective improvement in cognitive test scores of extremely low birthweight infants aged between 2 and 5 years

Abstract The cognitive development at 2 and 5 years of a cohort of extremely low birthweight (ELBW) children (birthweight 500-999 g) was compared with that of cohorts of larger very low birthweight (VLBW) children (birthweight 1000-1500 g) and normal birthweight (NBW) children (birthweight > 2500 g) to determine whether the improvements in cognitive function of ELBW infants between 2 and 5 years are apparent or real.
At 2 years of age, ELBW children had a mean Mental Developmental Index (MDI) on the Bayley Scales of 90.4, significantly lower than the means of 100.3 for the larger VLBW children ( P = 0.006), and 107.8 for the NBW children ( P = 0.0002). However by 5 years the mean scores on the Wechsler Preschool and Primary Scales of Intelligence (WPPSI) full-scale for the ELBW and larger VLBW children were virtually identical (105.9 and 106.0 respectively)—but still lower than the mean WPPSI full-scale of 114.6 for the NBW children. After standardizing the MDI and WPPSI scores relative to the NBW children, the ELBW children improved between 2 and 5 years (paired t -test, t = 3.2, P = 0.004) whereas the larger VLBW infants did not.
We postulate that ELBW children require more time than larger VLBW children after birth to compensate for perinatal and other stresses, and that developmental delay at 2 years may not always persist to 5 years.     

Extremely low–birth–weight infants less than 901 g: development and behaviour after 4 years of life

In a long–term, prospective, control study, 20 extremely low–birth–weight (ELBW) infants with birth weights between 500 and 900 g (mean 755 (SD 109) g) and gestational ages between 24 and 30 weeks (mean 26.2 (SD 1.8) weeks) were compared with 20 full–term infants at 4 years of age for growth, health, development and quality of life. Four of 20 (20%) ELBW children had major neurological disorders, which were all identified at the 1–year assessment. Seventeen (85%) ELBW children had cognitive development, assessed with the Griffiths mental development scale, within the normal range for age but lower than for full–term controls. The greatest deviations between ELBW and full–term children were found in locomotor and visual–motor integration functions. Eight ELBW children in all (40%), four with recurrent respiratory tract infections after neonatal mechanical ventilation and the four children with major neurological disorders had a higher rate of visits to physicians and hospital admissions. The behavioural symptom interview showed an increased rate of hyperactivity and difficulties in concentrating but not of general behavioural deviations in the ELBW group. Only by school age can all aspects of an extremely early birth be evaluated, but at 4 years of age, 85% of the ELBW children in our group had a good quality of life according to Scheffzek's categorizations.     

Surgery and the tiny baby: Sensorineural outcome at 5 years of age

O bjective : To determine whether an association exists between long-term sensorineural outcome and the need for surgery requiring general anaesthesia during the primary hospitalization in extremely preterm (> 27 weeks of gestational age) or extremely low birthweight (ELBW, birthweight > 1000g) infants.
Methodology : A geographically determined cohort study of extremely preterm or ELBW children in the State of Victoria, Australia. The study subjects were consecutive survivors with either gestational ages >27 weeks or birthweights >1000g born in the State of Victoria during 3 years from 1 January 1985. The main outcome measure was the rate of sensorineural disability at 5 or more years of age in relation to surgical procedures requiring general anaesthesia performed during the primary hospitalization.
Results : Of 221 children surviving to 5 years of age, 54 (24.4%) had at least one surgical operation requiring general anaesthesia during their primary hospitalization. The operations included the following: (i) ligation of ductus arteriosus ( n = 26); (ii) inguinal hernia repair ( n = 16); (iii) central nervous system surgery ( n = 4); (iv) gastrointestinal surgery ( n = 5); and (v) tracheostomy or bronchoscopy ( n = 5). Of the 221 survivors to 5 years of age, 218 (98.6%) were assessed for sensorineural impairments and disabilities. Of the 53 children who were assessed at 5 or more years of age and who had had surgery, 7 (13.2%) were severely disabled, 8 (15.1%) were moderately disabled, 12 (22.6%) were mildly disabled, and 26 (49.1%) were non-disabled. The overall rate of sensorineural disability was significantly higher in children who had been operated on compared with those who had not (Mann-Whitney U -test, z = 3.7, P > 0.001).
Conclusions : There is an adverse association between the need for surgery requiring general anaesthesia during the primary hospitalization and sensorineural outcome in extremely preterm or ELBW infants.     

Predicting IQ of biologically "at risk" children from age 3 to school entry: sensitivity and specificity of the Stanford-Binet Intelligence Scale IV

Predictive validity of the Stanford-Binet Intelligence Scale Fourth Edition (S-B IV) from age 3 years to ages 4-5 years was evaluated with biologically "at risk" children without major sensory or motor impairments (n = 236). Using the standard scoring, children with full scale IQ < or = 84 on the Wechsler Preschool and Primary Scale of Intelligence at age 4-5 years were poorly identified (sensitivity 54%) from the composite S-B IV score at age 3. However, sensitivity improved greatly to 78% by including as a predictor the number of subtests the child was actually able to perform at age 3 years. Measures from the Home Screening Questionnaire and ratings of mother-child interaction further improved sensitivity to 83%. The standard method for calculating the composite score on the S-B IV excludes subtests with a raw score of 0, which overestimates cognitive functioning in young biologically high risk children. Accuracy of early identification was improved significantly by considering the number of subtests the child did not perform at age 3 years.     

Developmental coordination disorder in extremely low birth weight children at nine years

Developmental coordination disorder (DCD) is defined as an impairment in the development of motor coordination that interferes with academic achievement or activities of daily living (DSM-IV). DCD has been reported to affect 5% to 9% of children in the normal population. This study describes the prevalence of DCD in a cohort of extremely low birth weight children (ELBW, < or = l800 g) at 8.9 years of age, from which were excluded children with major impairments. Seventy-three children were included in the study group, along with 18 term-born, socially matched controls. Of the 73 ELBW children, 37 (51%) were classified as having DCD. ELBW children with DCD also had significantly lower Performance IQ (PIQ) scores and were more likely (43%) to have a learning difficulty in arithmetic than ELBW children who did not have DCD. This study found that DCD is a common problem in school-aged ELBW children.     

Intellectual and functional status at school entry of children who weighed 1000 grams or less at birth: a regional perspective of births in the 1980s

The intellectual and functional status of a regional cohort of children who weighed 501 to 1000 gm when born between 1980 and 1982 was evaluated at a mean age of 5 1/2 years by standard psychometric tests. Of 90 long-term survivors (survival rate 49%), 78 children (87%) had the full test battery, 5 children (6%) had other tests (4 were blind), and one child was untestable. Most of the mean scores were within 1 SD of the test norms; the lowest scores were in the McCarthy Motor scale and in the Beery Test of Visual-Motor Integration. Children without neurologic impairments and those with an IQ greater than or equal to 68 (n = 60) had higher overall scores but still performed poorly on the Motor subscale and the Beery test. Children who weighed less than 800 gm at birth (n = 28) were similar to those who weighed greater than 800 gm (n = 50), except in the Memory and Motor subscales, in which they performed significantly less well. At a functional level, determined by the Vineland Adaptive Behaviour Scales, two thirds of the children were performing in the adequate range and the remainder in the moderately low to low range. Of the 43 children with no neurosensory impairments and an IQ greater than or equal to 84, 49% were identified (by the Florida Kindergarten Screening Battery) to be at mild to high risk for future learning disabilities. The data from this unselected population provide an unbiased estimate of the prevalence of intellectual and functional problems in children who weighed less than or equal to 1000 gm at birth.     

Outcome at 14 years of extremely low birthweight infants: a regional study

OBJECTIVES: To determine the neurosensory outcome at 14 years of age of a regional cohort of extremely low birthweight (ELBW) children, to contrast their prognosis with normal birthweight (NBW) controls, and to determine the predictive value of assessments earlier in childhood. DESIGN: Geographically determined cohort study. SETTING: The state of Victoria, Australia. PATIENTS: Consecutive ELBW survivors of birth weight 500-999 g (n = 88) born during 1979-1980, and 60 randomly selected contemporaneous NBW (birth weight > 2499 g) controls. MAIN OUTCOME MEASURES: Rates of neurosensory impairments and disabilities at 14 years of age, and earlier in childhood. RESULTS: Of 351 ELBW consecutive live births, 88 (25%) survived and 79 (90%) of the survivors were assessed at 14 years of age. Of the 79 ELBW children assessed, eight (10%) had cerebral palsy, five (6%) had bilateral blindness, four (5%) were deaf requiring hearing aids, and 36 (46%) had an intelligence quotient (IQ) < -1 SD compared with the mean for the NBW controls. Overall 11 (14%) ELBW children were severely disabled, 12 (15%) were moderately disabled, 20 (25%) were mildly disabled, and 36 (46%) had no disability. In contrast, only one (2%) of 42 NBW children assessed had a severe disability, six (14%) had a mild disability, and the remaining 35 (83%) were not disabled. Comparing psychological test scores for ELBW children with those for NBW controls, rather than test norms, avoided bias in the assessment of disability earlier in childhood. Relative to assessments earlier in childhood, the prediction of disability at 14 years of age was highly significant at each of 2, 5, and 8 years of age, but the accuracy progressively increased with age. CONCLUSIONS: ELBW children have substantially higher rates of neurosensory impairments and disabilities at 14 years of age than NBW controls. Comparison of ELBW children with NBW controls avoids bias in the assessment of disability. Early childhood assessments are highly predictive of disability at 14 years of age.     

Can learning disabilities in children who were extremely low birth weight be identified at school entry?

This prospective study was designed to test the hypothesis that a significant proportion of extremely low birth weight (ELBW) children identified as "at risk" for school problems at age 5 years by the Florida Kindergarten Screening Battery (FKSB) will present with specific learning disability (LD) when retested at age 8 years. A regional cohort of 81 of 84 ELBW survivors born between 1980 and 1982 were reassessed at age 8 years by Wechsler Intelligence Scale for Children-Revised (WISC-R), Wide Range Achievement Test-Revised (WRAT-R), and tests of motor function. The association of FKSB risk status and WRAT-R reading subtest for predicting general reading disability in the overall sample at age 8 years resulted in a sensitivity of 0.68, specificity of 0.48, and a likelihood ratio of 1.3. Of the 43 "normal" children at age 5 years with no neurosensory impairments and IQ > or = 84 (McCarthy GCI), 49% were considered to be at "mild" to "high" risk for future LD. The prevalence of specific LD (reading disorder) at age 8 years in children with normal IQ (WISC-R > or = 85) was 28%. The positive predictive value of the 5-year FKSB for identifying children with specific LD at age 8 years was 0.20 (sensitivity 0.33, specificity 0.48). We conclude the FKSB is not an efficient tool for predicting either general or specific LD in ELBW children.     

Incidence and pattern of hearing impairment in children with ≤ 800 g birthweight in British Columbia, Canada

Aim: This study aimed to evaluate changes over time in the characteristics of permanent hearing impairment (HI) in extremely low‐birthweight (ELBW ≤800 g) children. Methods: Data from sequential visits up to 5 years of age assessing hearing and other neurodevelopmental outcomes were extracted from a cohort of ELBW subjects born between 1983 and 2006 at a single Canadian site. Trends in HI incidence, severity and association with other impairments were analysed in three 8‐year epochs. Results: Fifty of 586 ELBW children had a HI. HI rates increased from 5% in epoch 1 to 7% in epoch 2–13% in epoch 3 (p = 0.01). Mild HI decreased from 78% in epoch 1 to 35% in epoch 3 (p = 0.03). Median age at diagnosis decreased from 13 to 8 months. Comorbidities were more common in HI children than non‐HI children: cerebral palsy (40% vs 14%, p < 0.0001)), cognitive (38% vs 12%, p < 0.0001) and visual impairments (16% vs 6%, p = 0.009). Conclusion: The incidence and severity of hearing impairment in a cohort of extremely low‐birthweight children increased significantly from 5% to 13% (p = 0.01) over a 24‐year period. Comorbidities were common. Potentially modifiable causes are explored.     

Children's Judgements about Pain at Age 8–10 Years: Do Extremely Low Birthweight (≤ 1000 g) Children Differ from Full Birthweight Peers?

Children's judgements about pain at age 8–10 years were examined comparing two groups of children who had experienced different exposure to nociceptive procedures in the neonatal period: extremely low birthweight (ELBW) ≤ 1000 g ( N = 47) and full birthweight (FBW) ≤ 2500 g ( N = 37). The 24 pictures that comprise the Pediatric Pain Inventory, depicting events in four settings: medical, recreational, daily living, and psychosocial, were used as the pain stimuli. The subjects rated pain intensity using the Color Analog Scale and pain affect using the Facial Affective Scale. Child IQ and maternal education were statistically adjusted in group comparisons. Pain intensity and pain affect related to activities of daily living and recreation were significantly higher than psychosocial and medically related pain on both scales in both groups of children. Although the two groups of children did not differ overall in their perceptions of pain intensity or affect, the ELBW children rated medical pain intensity significantly higher than psychosocial pain, unlike the FBW group. Also, duration of neonatal intensive care unit stay for the ELBW children was related to increased pain affect ratings in recreational and daily living settings. Despite altered response to pain in the early years reported by parents, on the whole at 8–10 years of age ELBW children judged pain in pictures similarly to their term peers. However, differences were evident, which suggests that studies are needed of biobehavioural reactivity to pain beyond infancy, as well as research into beliefs, attitudes, and perceptions about pain during the course of childhood in formerly ELBW children.     

Selective improvement in cognitive test scores of extremely low birthweight infants aged between 2 and 5 years

The cognitive development at 2 and 5 years of a cohort of extremely low birthweight (ELBW) children (birthweight 500-999 g) was compared with that of cohorts of larger very low birthweight (VLBW) children (birthweight 1000-1500 g) and normal birthweight (NBW) children (birthweight greater than 2500 g) to determine whether the improvements in cognitive function of ELBW infants between 2 and 5 years are apparent or real. At 2 years of age, ELBW children had a mean Mental Developmental Index (MDI) on the Bayley Scales of 90.4, significantly lower than the means of 100.3 for the larger VLBW children (P = 0.006), and 107.8 for the NBW children (P = 0.0002). However by 5 years the mean scores on the Wechsler Preschool and Primary Scales of Intelligence (WPPSI) full-scale for the ELBW and larger VLBW children were virtually identical (105.9 and 106.0 respectively)--but still lower than the mean WPPSI full-scale of 114.6 for the NBW children. After standardizing the MDI and WPPSI scores relative to the NBW children, the ELBW children improved between 2 and 5 years (paired t-test, t = 3.2, P = 0.004) whereas the larger VLBW infants did not. We postulate that ELBW children require more time than larger VLBW children after birth to compensate for perinatal and other stresses, and that developmental delay at 2 years may not always persist to 5 years.     

Survival and neurodevelopmental outcome of ELBW children at 5 years of age: comparison of two cohorts born 10 years apart

Aim: To examine survival and outcome of extremely low‐birth‐weight (ELBW) children (birth weight < 1000 g) in two 5‐year periods, 10 years apart. Methods: In a retrospective population‐based study, information on all ELBW children born in Iceland in 1991–1995 and in 2001–2005 was obtained from the National Birth Registry, hospital charts and medical records. The two periods were compared. Results: In 1991–1995, 102 of 22.261 newborn children (0.5%) were extremely low birth weight compared with 70 of 20.923 newborns (0.33%) in 2001–2005 (p = 0.04). At 5 years of age, 52% (35/67) of live‐born children born in 1991–1995 were alive compared with 63% (31/49) of children born in 2001 – 2005 (p = 0.2). Six ELBW children (17%) born 1991–1995 were diagnosed with disabilities at 5 years of age, three with major neurodevelopmental disabilities compared with six (19%) born 2001–2005, thereof one with severe neurodevelopmental disabilities (p = 0.57). Conclusion: The incidence of childhood disabilities in ELBW children in Iceland remains stable despite an increase in survival rate. The severity of neurodevelopmental disabilities has decreased.     

Psychometric Properties of the Canadian Little Developmental Coordination Disorder Questionnaire for Preschool Children

ABSTRACT

Aims: Test the psychometric properties and cut-off scores for the Canadian Little Developmental Coordination Disorder Questionnaire (Little DCDQ), which screens for coordination difficulties in children aged 3 to 4 years. Methods: Parents of children with typical development (n = 108) and children at risk for motor problems (n = 245) completed the questionnaire. A subgroup (n = 119) of children was tested with the Movement Assessment Battery for Children-2 (MABC-2) and the Beery–Buktenica Developmental Test of visual-motor integration (VMI) to determine motor impairment (MI). Results: Test-retest reliability (r = 0.956, p < .001) and internal consistency (Cronbach's alpha = 0.94) were high. Construct validity was supported by a factor analysis and significant difference in scores of children who were typically developing and were at risk. Concurrent validity was evaluated for the children who received standardized motor testing, with significant difference between children with and without MI. Discriminant function analysis showed that all 15 items were able to distinguish the two groups. The questionnaire correlated well with the MABC-2 and VMI. Validity as a screening tool was assessed using logistic regression modeling (X²(5) = 25.87, p < .001) and receiver operating curves, establishing optimal cut-off values with adequate sensitivity. Conclusions: The Little DCDQ is a reliable, valid instrument for early identification of children with motor difficulties.