Classification of events contributing to postneonatal cerebral palsy: Development, reliability, and recommendations for use.

AIM: This paper introduces the Surveillance of Cerebral Palsy in Europe (SCPE) classification of events contributing to postneonatally acquired cerebral palsy, presents its interrater reliability, and describes the cases identified in the SCPE database. METHOD: The development of the classification, based on literature review and expert discussions, resulted in six main categories and 19 subcategories. The first chronological event designated as the primary event was mainly reported. Interrater reliability was assessed through online exercise providing 24 clinical vignettes representing single/complex pathways. Percent agreement and Gwet's AC1 index of reliability were estimated. Primary events were described using data of 221 children born between 2008 and 2012. RESULTS: Thirty-nine professionals (21 registries) participated in the reliability exercise. Substantial overall agreement was reached (0.75), with some contrast between complex (0.48, moderate agreement) and single events involved (0.89, almost perfect). The distribution of primary events showed that 32.1% were infections (category A), 23.1% head injuries (B), 15.4% related to surgery or medical interventions (C), 13.1% cerebrovascular accidents (D), 9.1% hypoxic brain damaging events of other origins (E), and 7.2% miscellaneous (F). INTERPRETATION: This classification allows all the events involved to be recorded while consistently reporting the primary event, and may be used in different settings. WHAT THIS PAPER ADDS: A standardized classification enables the description of the events contributing to postneonatal cerebral palsy (CP). The first chronological event in complex pathway leading to CP is coded. Category choice and coding of the primary event identify preventable situations. The detailed 2-level classification is easy to use in various settings. Substantial overall interrater reliability shows that main categories can be consistently differentiated.

Does botulinum neurotoxin A make walking easier in children with cerebral palsy? A randomized clinical trial.

AIM: To assess the effect of single botulinum neurotoxin A (BoNT-A) injections into the calf muscles on the gross energy cost of walking in children with cerebral palsy (CP) and to evaluate the effect of BoNT-A on walking capacity, physical activity, perceived changes in mobility, and pain. METHOD: This was an industry-independent, randomized, quadruple-blind, placebo-controlled, multicentre trial (ClinicalTrials.gov registration: NCT02546999). Sixty-one children (33 male, median age [range] = 8 years [4-16 years]) with spastic CP and classified in Gross Motor Function Classification System (GMFCS) levels I and II allocated to single injections of either BoNT-A or 0.9% saline into the calf muscles. The main outcome was gross energy cost (J/kg/m); secondary outcomes were walking capacity, habitual physical activity, perceived change in mobility tasks, and calf pain at baseline, 4 weeks (P1), 12 weeks (P2), and 24 weeks (P3) after the injection. RESULTS: The mean change in energy cost did not differ significantly between groups at the primary time point P2 (-0.27 J/kg/m, 95% confidence interval - 0.91 to 0.36, p = 0.404), nor at P1 or P3. Regarding the secondary outcomes, there was some evidence of a larger reduction in pain intensity in the group given BoNT-A (p = 0.043). INTERPRETATION: One treatment with BoNT-A was not superior to placebo in making walking easier in children with CP classified in GMFCS levels I and II, at least in the short term. BoNT-A may have a pain-reducing effect.

Prevalence, birth, and clinical characteristics of dyskinetic cerebral palsy compared with spastic cerebral palsy subtypes: A Norwegian register-based study.

AIM: To study the prevalence, birth, and clinical characteristics of children with dyskinetic cerebral palsy (CP) in Norway compared with spastic quadriplegic CP and other spastic CP subtypes. METHOD: Data on children born from 1996 to 2015 were collected from the Norwegian Quality and Surveillance Registry for Cerebral Palsy and the Medical Birth Registry of Norway. RESULTS: One hundred and seventy (6.8%) children had dyskinetic CP. The birth prevalence decreased during 1996 to 2015 from 0.21 to 0.07 per 1000 livebirths (p < 0.001). Dyskinetic CP was more often associated with term/post-term birth, and motor and associated impairments were more severe compared with spastic bilateral and unilateral CP, but less severe than spastic quadriplegic CP. On neuroimaging, grey matter injuries were most prevalent in dyskinetic CP (mainly basal ganglia/thalamus) and spastic quadriplegic CP (mainly cortico-subcortical), white matter injuries in spastic bilateral, and white and grey matter injuries were equally common in spastic unilateral CP. Normal neuroimaging and brain maldevelopment were present in 25% of children with dyskinetic CP. INTERPRETATION: The decrease in birth prevalence of dyskinetic CP was probably due to improved antenatal and perinatal care. Potential sentinel events at term were more common in dyskinetic CP than other spastic CP subtypes. However, probable antenatal aetiologies were most prevalent. Motor and associated impairments were less severe in children with dyskinetic CP compared with spastic quadriplegic CP. WHAT THIS PAPER ADDS: Birth prevalence of those with dyskinetic and spastic bilateral cerebral palsy (CP) in Norway decreased between 1996 and 2015. Potential sentinel events at term were more common in dyskinetic CP. Nonetheless, probable antenatal aetiologies were most prevalent in dyskinetic CP. Basal ganglia/thalamus lesions were more common in dyskinetic than spastic quadriplegic CP. Motor and associated impairments were milder in dyskinetic than spastic quadriplegic CP.

Cerebral palsy in children born after assisted reproductive technology in Norway: Risk, prevalence, and clinical characteristics.

INTRODUCTION: The aim was to investigate the risk, prevalence, and clinical characteristics of cerebral palsy among children born after assisted reproductive technology (ART) in Norway. MATERIAL AND METHODS: All liveborn children from 2002 to 2015 were included. Information was collected from the Medical Birth Registry of Norway, linked to the Norwegian Quality and Surveillance Registry for Cerebral Palsy as of December 31, 2022. Logistic regression analyses were used to calculate the prevalence of cerebral palsy per 1000 live births after ART and natural conception with birth year as covariate, crude odds ratios (OR) for cerebral palsy among children born after ART using children born after natural conception as reference, and OR adjusted for potential confounders, with 95% confidence intervals (CI). Potential mediators of the association were studied in stratified analyses. Descriptive statistics were used to compare proportions in clinical characteristics among children with cerebral palsy born after ART and natural conception. RESULTS: Among 833 645 livebirths, 23 645 children were born after ART and of the latter 97 were diagnosed with cerebral palsy. The overall prevalence of cerebral palsy after ART was 4.10 per 1000 live births (95% CI 3.36-5.00), decreasing from 7.79 per 1000 in 2002 to 3.55 in 2015. Compared with children born after natural conception, the OR for cerebral palsy was 2.01 (95% CI 1.63-2.47) adjusted for mother's age at birth, parity, and pre-pregnancy health. When restricted to singletons born at term, the adjusted OR for cerebral palsy was 1.13 (95% CI 0.76-1.69). The distribution of cerebral palsy subtypes and the severity of gross and fine motor function and associated impairments did not differ significantly between children with cerebral palsy born after ART and natural conception. CONCLUSIONS: Children born after ART had a risk of cerebral palsy that was twice that of children born after natural conception. The increased risk of cerebral palsy after ART is likely attributed to multiple pregnancies and preterm births. The prevalence of cerebral palsy after ART decreased significantly during the study period, despite an increased use of ART in the population. The distribution of clinical characteristics did not differ between children with cerebral palsy born after ART and those born after a natural conception, suggesting that the risk factors for, and causes of cerebral palsy were similar.

Norwegian paediatric habilitation centres judge their own competence on cerebral visual impairment as limited.

AIM: Cerebral visual impairment (CVI), a frequently occurring functional impairment in children with neurodevelopmental disorders, leads to communicative, social and academic challenges. In Norway, children with neurodevelopmental disorders are assessed at paediatric habilitation centres. Our aims were to explore how CVI is identified, how paediatric habilitation centres assess their CVI competence and the reported prevalence of CVI among children with cerebral palsy. METHODS: An electronic questionnaire was sent to all 19 Norwegian paediatric habilitation centre leaders in January 2022. The results were analysed quantitatively and qualitatively. The prevalence of CVI among children with cerebral palsy was estimated using register-based data. RESULTS: The questionnaire was answered by 17. Only three judged their habilitation centre as having sufficient competence on CVI. None of the centres used screening questionnaires systematically, and 11 reported that CVI assessment was not good enough. Awareness that a child may have CVI typically occurred during examinations for other diagnoses. The prevalence of CVI among children with cerebral palsy was only 8%, while CVI status was unknown in 33%. CONCLUSION: Better knowledge and assessment of CVI at Norwegian paediatric habilitation centres are needed. CVI appears to be often overlooked in children with neurodevelopmental disorders.

External validity of the Both Hands Assessment for evaluating bimanual performance in children with bilateral cerebral palsy.

AIM: To investigate the external validity of the Both Hands Assessment (BoHA), a new test evaluating bimanual performance in children with bilateral cerebral palsy (CP), by analysing its relationship to established measurements of hand function and self-care skills. METHOD: In this cross-sectional study, we recruited children with bilateral CP and manual ability corresponding to Manual Ability Classification System (MACS) levels I to III attending three habilitation units in Norway. All participants completed the BoHA. Unimanual capacity was assessed using the Bimanual Fine Motor Function (BFMF) classification, the Box and Block Test (BBT), and the Melbourne Assessment 2 (MA2). Self-care skills were assessed with the Pediatric Evaluation of Disability Inventory (PEDI). RESULTS: Thirty-nine children (19 males, 20 females; mean age 8y 2mo, SD 2y 8mo; age range 2y 8mo-12y 6mo) were included. Spearman's correlation coefficient (ρ) suggested high correlation between the BoHA and MACS (p=0.89; 95% confidence interval [CI] 0.79-0.94), BFMF classification (p=0.84; 95% CI 0.71-0.91), and BBT for the non-dominant (p=0.85; 95% CI 0.68-0.95) and dominant hand (p=0.72; 95% CI 0.53-0.85). The Spearman's ρ between the BoHA and the MA2 subscales varied between 0.48 and 0.83, while the PEDI's ρ was 0.51 (95% CI 0.33-0.67). INTERPRETATION: The BoHA provides valid measures of hand use as suggested by its high correlation with other activity-based measures of hand function.

High occurrence of perinatal risk factors and more severe impairments in children with postneonatal cerebral palsy in Norway.

AIM: To describe causal events, perinatal risk factors and clinical characteristics in children with postneonatal cerebral palsy (PNCP). METHODS: Population-based registry study of Norwegian children born 1999-2013. Prevalence, causal events and clinical characteristics of PNCP were described. The occurrence of perinatal risk factors for CP was compared with the general population. RESULTS: Among 1710 children with CP, 67 had PNCP (3.9%; 0.75 per 10,000 livebirths [95%CI: 0.59-0.96]). The prevalence of PNCP decreased during the study period. Leading causal events were cerebrovascular events (32.8%), head injuries/other accidents (22.4%), infections (19.4%) and hypoxic events (14.9%). Spastic hemiplegic (53.7%) or spastic quadriplegic/dyskinetic CP (31.3%) was more common in children with PNCP than non-PNCP (42.3% and 20.1%, respectively; p < 0.001). Children with PNCP had more severe motor and associated impairments. Perinatal risk factors for CP were more common in children with PNCP than in the general population. CONCLUSION: The prevalence of PNCP among Norwegian children was low and decreasing. The main causes were cerebrovascular events and head injuries/other accidents. Although spastic hemiplegic CP was the dominating subtype, children with PNCP had more severe motor and associated impairments than children with non-PNCP, as well as a higher occurrence of perinatal risk factors than in the general population.

Incidence of invasive Group B Streptococcal infection and the risk of infant death and cerebral palsy: a Norwegian Cohort Study.

BACKGROUND: Group B Streptococcus (GBS) is the leading cause of invasive neonatal infection worldwide. In high-income countries mortality rates are 4-10%, and among survivors of GBS meningitis 30-50% have neurodevelopmental impairments. We hypothesized that invasive GBS infection was associated with increased risk of infant mortality and cerebral palsy (CP). METHODS: All children born alive in Norway during 1996-2012 were included. Data were collected from three national registers. Invasive GBS infection during infancy was categorized into early-onset disease (EOD), late-onset disease (LOD), and very late-onset disease (VLOD). Primary outcomes were infant mortality and CP. RESULTS: Invasive GBS infection was diagnosed in 625 children (incidence: 0.62 per 1000 live births; 95% confidence interval (CI): 0.57-0.67). The incidence of EOD was 0.41 (0.37-0.45), of LOD 0.20 (0.17-0.23), and of VLOD 0.012 (0.007-0.021). The annual incidence of LOD increased slightly. Among infected infants, 44 (7%) died (odds ratio (OR): 24.5; 95% CI: 18.0-33.3 compared with the background population). Among survivors, 24 (4.1%) children were later diagnosed with CP, compared with 1887 (0.19%) in the background population (OR: 22.9; 95% CI: 15.1-34.5). CONCLUSION: Despite a relatively low incidence of invasive GBS infection in Norway, the risk of death and CP remains high. Improvements in prevention strategies are needed. IMPACT: During the first decade of the twenty-first century, invasive GBS disease in infancy is still associated with high mortality. Despite the overall low incidence of invasive GBS disease, the incidence of LOD increased during the study period. The finding that invasive GBS infection in the neonatal period or during infancy is associated with an excess risk of CP, comparable to the risk following moderate preterm birth and moderate low Apgar scores, adds to the existing literature. The results of this study emphasize the importance of adhering to guidelines and the need for better prevention strategies.

Access to Intrathecal Baclofen Treatment for Children with Cerebral Palsy in European Countries: An SCPE Survey Reveals Important Differences.

AIM: The aim is to study access to intrathecal baclofen (ITB) for children with cerebral palsy (CP) in Europe, as an indicator of access to advanced care. METHODS: Surveys were sent to CP registers, clinical networks, and pump manufacturers. Enquiries were made about ITB treatment in children born in 1990 to 2005 by sex, CP type, level of gross motor function classification system (GMFCS) and age at the start of treatment. Access to ITB was related to the country's gross domestic product (GDP) and % GDP spent on health. RESULTS: In 2011 population-based data from Sweden, Norway, England, Portugal, Slovenia, and Denmark showed that 114 (3.4%) of 3,398 children with CP were treated with ITB, varying from 0.4 to 4.7% between centers. The majority of the children were at GMFCS levels IV-V and had bilateral spastic CP. In Sweden, dyskinetic CP was the most commonly treated subtype. Boys were more often treated with ITB than girls (p = 0.014). ITB was reported to be available for children with CP in 25 of 43 countries. Access to ITB was associated with a higher GDP and %GDP spent on health (p < 0.01). Updated information from 2019 showed remaining differences between countries in ITB treatment and sex difference in treated children was maintained. CONCLUSION: There is a significant difference in access to ITB for children with CP across Europe. More boys than girls are treated. Access to ITB for children with CP is associated with GDP and percent of GDP spent on health in the country.

Comorbidities in cerebral palsy: a patient registry study.

AIM: To describe the total burden of disease in individuals with cerebral palsy (CP) in Norway. METHOD: A comprehensive set of disorder categories were extracted from the Norwegian Patient Registry using International Statistical Classification of Diseases, 10th Revision diagnosis codes for individuals born between 1996 and 2010 who received specialist healthcare between 2008 and 2017 (0-21y). Individuals with CP were identified through a validation study in cooperation with the Cerebral Palsy Registry of Norway. Risk differences (proportions of individuals recorded with each disorder) were used to compare individuals with CP with the general population without CP. RESULTS: The study included 966 760 individuals. Among these, 2302 (0.24%) had CP (1330 males, 972 females). Of the individuals with CP, 95.0% were recorded with one or more comorbidity, and the risks of medical, neurological, and mental/behavioural disorders were higher compared with the risks in the general population. The most common neurological and mental/behavioural disorders were cocausal, i.e. attributed to the same injury to the developing brain that caused CP, while medical disorders were most often complications of CP or coincidentally co-occurring with CP. INTERPRETATION: Individuals with CP have a considerably higher burden of medical, neurological, and mental/behavioural disorders compared with the general population, including disorders that are not directly caused by, or complications to, the brain injury. WHAT THIS PAPER ADDS: Nearly all individuals with cerebral palsy (CP) had one or more comorbidity. Fifty-two per cent had at least one comorbidity attributed to the same cause as CP, complications of CP, and coincidentally co-occurring with CP. Risks of medical, neurological, and mental/behavioural disorders were considerably higher than in the general population.

Prelabor rupture of membranes and the association with cerebral palsy in term born children: a national registry-based cohort study.

BACKGROUND: Guidelines regarding management of prelabor rupture of membranes (PROM) at term vary between immediate induction and expectant management. A long interval between PROM and delivery increases the risk for perinatal infections. Severe perinatal infections are associated with excess risk for cerebral palsy (CP) and perinatal death. We investigated if increasing intervals between PROM and delivery were associated with perinatal death or CP. METHODS: Eligible to participate in this population-based cohort-study were term born singletons without congenital malformations born in Norway during 1999-2009. Data was retrieved from the Medical Birth Registry of Norway (MBRN) and the Cerebral Palsy Register of Norway. In line with the registration in the MBRN, intervals between PROM and delivery of more than 24 h was defined as 'prolonged' and intervals between 12 and 24 h as 'intermediate'. Outcomes were stillbirth, death during delivery, neonatal mortality and CP. Logistic regression was used to calculate odds ratio (OR) with 95% confidence intervals (CI) for adverse outcomes in children born after prolonged and intermediate intervals, compared with a reference group comprising all children born less than 12 h after PROM or without PROM. RESULTS: Among 559,972 births, 34,759 children were born after intermediate and 30,332 were born after prolonged intervals. There was no association between increasing intervals and death during delivery or in the neonatal period, while the prevalence of stillbirths decreased with increasing intervals. Among children born after intermediate intervals 38 (0.11%) had CP, while among those born after prolonged intervals 46 (0.15%) had CP. Compared with the reference group, the OR for CP was 1.16 (CI; 0.83 to 1.61) after intermediate and 1.61 (CI; 1.19 to 2.18) after prolonged intervals. Adjusting for antenatal factors did not affect these associations. Among children with CP the proportion with diffuse cortical injury and basal ganglia pathology on cerebral MRI, consistent with hypoxic-ischemic injuries, increased with increasing intervals. CONCLUSION: Intervals between PROM and delivery of more than 24 h were associated with CP, but not with neonatal mortality or death during delivery. The inverse association with stillbirth is probably due to reverse causality.

Adherence to guidelines and suboptimal practice in term breech delivery with perinatal death- a population-based case-control study in Norway.

BACKGROUND: In a recent population-based study we reported excess risk of neonatal mortality associated with vaginal breech delivery. In this case-control study we examine whether deviations from Norwegian guidelines are more common in breech deliveries resulting in intrapartum or neonatal deaths than in breech deliveries where the offspring survives, and if these deaths are potentially avoidable. MATERIAL AND METHODS: Case-control study completed as a perinatal audit including term breech deliveries of singleton without congenital anomalies in Norway from 1999 to 2015. Deliveries where the child died intrapartum or in the neonatal period were case deliveries. For each case, two control deliveries who survived were identified. All the included deliveries were reviewed by four obstetricians independently assessing if the deaths in the case group might have been avoided and if the management of the deviations from Norwegian guidelines were more common in case than in control deliveries. RESULTS: Thirty-one case and 62 control deliveries were identified by the Medical Birth Registry of Norway. After exclusion of non-eligible deliveries, 22 case and 31 control deliveries were studied. Three case and two control deliveries were unplanned home deliveries, while all in-hospital deliveries were in line with national guidelines. Antenatal care and/or management of in-hospital deliveries was assessed as suboptimal in seven (37%) case and two (7%) control deliveries (p = 0.020). Three case deliveries were completed as planned caesarean delivery and 12 (75%) of the remaining 16 deaths were considered potentially avoidable had planned caesarean delivery been done. In seven of these 16 deliveries, death was associated with cord prolapse or difficult delivery of the head. CONCLUSION: All in-hospital breech deliveries were in line with Norwegian guidelines. Seven of twelve potentially avoidable deaths were associated with birth complications related to breech presentation. However, suboptimal care was more common in case than control deliveries. Further improvement of intrapartum care may be obtained through continuous rigorous training and feedback from repeated perinatal audits.

Use of botulinum toxin A in children with cerebral palsy. / Bruk av botulinumtoksin A til barn med cerebral parese.

BACKGROUND: For more than 20 years, intramuscular injections of botulinum toxin A have been an established treatment for spasticity in children with cerebral palsy. We investigated the proportion of children with cerebral palsy who receive such treatment in Norway and the guidelines that apply to the treatment. MATERIAL AND METHOD: Data from the five-year registration in the Cerebral Palsy Registry of Norway were used to investigate the proportion of children with cerebral palsy born in the period 1999-2010 treated with botulinum toxin A, and whether there were any variations in the proportion of children treated between the habilitation centres. We conducted an online survey to identify the treatment guidelines that were applied in all of the 21 habilitation centres. RESULTS: A total of 1 414 children (average age 6.3 years) were included, of whom 775 (55 %) had been treated with botulinum toxin A. The proportion of children who received treatment varied considerably between the habilitation centres (38-80 %; p < 0.001). The maximum dose of botulinum toxin A per treatment per patient was 200-600 units of Botox. Five centres reported to have written guidelines for the treatment indication. INTERPRETATION: The proportion of children with cerebral palsy who are treated with botulinum toxin A varies considerably between Norwegian habilitation centres.

Maternal smoking during pregnancy and offspring overweight: is there a dose-response relationship? An individual patient data meta-analysis.

BACKGROUND/OBJECTIVES: A number of meta-analyses suggest an association between any maternal smoking in pregnancy and offspring overweight obesity. Whether there is a dose-response relationship across number of cigarettes and whether this differs by sex remains unclear. SUBJECT/METHODS: Studies reporting number of cigarettes smoked during pregnancy and offspring BMI published up to May 2015 were searched. An individual patient data meta-analysis of association between the number of cigarettes smoked during pregnancy and offspring overweight (defined according to the International Obesity Task Force reference) was computed using a generalized additive mixed model with non-linear effects and adjustment for confounders (maternal weight status, breastfeeding, and maternal education) and stratification for sex. RESULTS: Of 26 identified studies, 16 authors provided data on a total of 238,340 mother-child-pairs. A linear positive association was observed between the number of cigarettes smoked and offspring overweight for up to 15 cigarettes per day with an OR increase per cigarette of 1.03, 95% CI = [1.02-1.03]. The OR flattened with higher cigarette use. Associations were similar in males and females. Sensitivity analyses supported these results. CONCLUSIONS: A linear dose-response relationship of maternal smoking was observed in the range of 1-15 cigarettes per day equally in boys and girls with no further risk increase for doses above 15 cigarettes.

The Placenta in Neonatal Encephalopathy: A Case-Control Study.

OBJECTIVE: We assessed whether specific histologic placental lesions were associated with risk for neonatal encephalopathy, a strong predictor of death or cerebral palsy. STUDY DESIGN: Case-control study of singletons with gestational ages ≥35 weeks. Data were abstracted from a prospectively collected database of consecutive births at a hospital in which placental samples from specified sites are collected and stored for all inborn infants. Placentas of infants with neonatal encephalopathy were compared with randomly selected control infants (ratio of 1:3). Placental histologic slides were read by a single experienced perinatal pathologist unaware of case status, using internationally recommended definitions and terminology. Findings were grouped into inflammatory, maternal, or fetal vascular malperfusion (FVM) and other lesions. RESULTS: Placental samples were available for 73 of 87 (84%) cases and 253 of 261 (97%) controls. Delivery complications and gross placental abnormalities were more common in cases, of whom 4 died. Inflammation and maternal vascular malperfusion did not differ, and findings consistent with global FVM were more frequent in case (20%) than control (7%) placentas (P = .001). There was a trend toward more segmental FVM and high-grade FVM (fetal thrombotic vasculopathy) among cases. Some type of FVM was observed in 24% of placentas with neonatal encephalopathy. In infants with both neonatal encephalopathy and placental FVM, more often than in infants with neonatal encephalopathy without FVM, electronic fetal monitoring tracings were considered possibly or definitely abnormal (P = .028). CONCLUSIONS: Vascular malperfusion of subacute or chronic origin on the fetal side of the placenta was associated with increased risk of neonatal encephalopathy.

Development and Validation of the Both Hands Assessment for Children With Bilateral Cerebral Palsy.

AIMS: To develop a hand function test for children with bilateral cerebral palsy (CP) measuring bimanual performance, including quantification of possible asymmetry of hand use. METHOD: The Both Hands Assessment (BoHA) content was developed through adaptation of the Assisting Hand Assessment (version 5.0). Data from 171 children with bilateral CP, 22-months to 13 years olds (75 females; mean age: 6 years and 6 months) classified at Manual Ability Classification System (MACS) levels I-III, was entered into Rasch measurement model analyses to evaluate internal scale validity and aspects of reliability. RESULTS: Sixteen items (11 unimanual and 5 bimanual) exhibited evidence for good internal scale validity and item and person reliability when analyzed separately for children with asymmetric or symmetric hand use. By calibrating the BoHA logit measures into the same frame of reference through linking, the overall measure of bimanual performance is comparable between children with asymmetric or symmetric hand use, still allowing use of separate item difficulty hierarchies. CONCLUSIONS: The Both Hands Assessment (BoHA), showed strong evidence of internal construct validity for measuring effectiveness of bimanual performance and the extent of asymmetric hand use in children with bilateral cerebral palsy, MACS levels I-III.

Completeness and correctness of cerebral palsy diagnoses in two health registers: implications for estimating prevalence.

AIM: To assess completeness and correctness of cerebral palsy (CP) diagnoses in the Cerebral Palsy Register of Norway (CPRN) and the Norwegian Patient Register (NPR), and to estimate CP prevalence. METHOD: Among 747 883 Norwegian residents born from 1996 to 2007, 2231 had a diagnosis of CP in the NPR while 1441 were registered in the CPRN. Children registered in the CPRN were considered to have a valid CP diagnosis. For those with a diagnosis of CP only in the NPR, two paediatricians reviewed the hospital records. The prevalence rate of CP with 95% confidence intervals (CI) was calculated on the basis of the combined data sets. RESULTS: One thousand three hundred and ninety-eight children were registered with a diagnosis of CP in both registers, 43 children were only registered in the CPRN, and 824 only in the NPR. The review of hospital records revealed that 464 (59.5%) had CP. Thus, the NPR was 98% complete, and for 86% the diagnosis was correct. The completeness of the CPRN was 76%, while the diagnosis was considered correct for all children (100%). The resulting prevalence of CP was 2.5 (95% CI 2.4-2.7) per 1000. INTERPRETATION: To gain accurate estimates of prevalence rates of CP, it is essential to combine data sources and to validate register data.

Congenital anomalies and the severity of impairments for cerebral palsy.

AIM: To study the prevalence of congenital anomalies among children with cerebral palsy (CP) born at term or late preterm, and if CP subtypes and clinical manifestations differ between children with and without congenital anomalies. METHOD: This was a cross-sectional study using data from the Cerebral Palsy Register of Norway and the Medical Birth Registry of Norway. All children with congenital CP born at and later than 34 weeks' gestation in Norway from 1999 to 2009 were included. Anomalies were classified according to the European Surveillance of Congenital Anomalies classification guidelines. Groups were compared using Fisher's exact test, Kruskal-Wallis test, and the Mann-Whitney U test. RESULTS: Among 685 children with CP, 169 (25%) had a congenital anomaly; 125 within the central nervous system. Spastic bilateral CP was more prevalent in children with anomalies (42%) than in children without (34%; p=0.011). Children with anomalies less frequently had low Apgar scores (p<0.001), but more often had severe limitations in gross- and fine-motor function, speech impairments, epilepsy, severe vision, and hearing impairments than children without anomalies (p<0.03). INTERPRETATION: Although children with CP and anomalies had low Apgar scores less frequently, they had more severe limitations in motor function and more associated problems than children with CP without anomalies. WHAT THIS PAPER ADDS: One in four children with cerebral palsy (CP) born at term or late preterm has a congenital anomaly. The added value of neuroimaging to detect central nervous system anomalies in children with CP. Children with anomalies have more severe motor impairments. More severe clinical manifestations are not explained by perinatal complications as indicated by low Apgar scores.