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Daily experience with product designers, test and diagnosis engineers it is realized that the depth of interaction among them, ought be high for sucessfull diagnosis of analogue circuits. With this knowledge in mind, a responsibility was undertaken to choose a popular diagnostic method and define a systematic procedure that binds together the knowledge of a product from a design, test and diagnostic engineer. A set of software utilities was developed that assists in automating these procedures and in collecting appropriate data for effective diagnosis of analogue circuits. This paper will discuss the chosen methodology for diagnosis and the associated procedures for block-level diagnosis of analogue electronic circuits in detail. The paper is concluded with an illustration of the methodology and the related procedures of an industrial automotive voltage regulator circuit as a representative example. © 2010 EDAA.

To determine whether correction for preterm birth should be applied during developmental assessment, we conducted a prospective national survey of very premature infants (born at less than 32 weeks of gestation); neurodevelopment in the first 2 years was studied with the Dutch child health care developmental assessment. In 555 preterm children who had no evidence of handicap at 2 years of age, the age at which developmental milestones were reached was established. The results were compared with the results of the same assessment in Dutch children born at term. During the first year, the development of the very premature children equaled the development of normal children when full correction was applied. At 2 years of age, development was equal to or better than normal children's development without correction. We conclude that full correction for prematurity should be applied in the first year to avoid overreferral for developmental stimulation, whereas at 2 years of age correction is not necessary.

Objective. To assess the effect of demographic and neonatal risk factors and outcome at the last available assessment on the probability of full responders, postal responders (those who only responded to the mailed questionnaire), or nonresponders in a follow-up study of 19-year-old adolescents who were born as preterm infants. Design. The 19-year follow-up program was part of a large ongoing collaborative study in the Netherlands on the long-term effect of prematurity and dysmaturity on various medical, psychological, and social parameters. In the original cohort, 1338 infants (94%) with a gestational age of <32 weeks and/or a birth weight of <1500 g were enrolled. Neonatal mortality was 23% (n = 312), and another 67 children had died between the ages of 28 days and 19 years, leaving 959 survivors (72% of the original cohort) for follow-up at the present assessment. To study the effect of nonresponse, we divided the 959 survivors into 3 groups: full responders (596 [62.1%]), postal responders (109 [11.4%]), and nonresponders (254 [26.5%]). In the 3 groups we compared demographic and neonatal data, as well as outcome at the last available assessment. Results. The odds ratios (ORs) for male versus female for the probabilities of nonresponse and postal response were statistically significant: 2.7 (95% CI: 1.9-3.9) and 1.6 (95% CI: 1.0-2.5), respectively. The same holds for the ORs for non-Dutch versus Dutch and low versus high maternal education for nonresponse: 2.0 (95% CI: 1.3-3.2) and 3.7 (95% CI: 2.0-6.7), respectively. Special education and severe handicap showed a statistically significant influence on nonresponse (OR: 1.6; 95% CI: 1.1-2.4 and OR: 2.6; 95% CI: 1.3-5.2) and postal response (OR: 2.0; 95% CI: 1.2-3.3 and OR: 4.4; 95% CI: 2.0-9.9), respectively. At the age of 19 years, primary school and special education were found significantly more frequent in the postal responders than in the full-response group (20% and 21% vs 6% and 12%). The full responders, on the other hand, were higher educated than were the postal responders. Conclusions. In this follow-up study at the age of 19 years, boys, non-Dutch adolescents, and low maternal education were overrepresented in the nonresponse and postal-response groups. Nonresponse decreased the proportion of infants with adverse outcome in assessed children. To be able to present reliable results for the total group of survivors in long-term follow-up studies, the nonresponse bias needs to be quantified. Therefore, it is evident that more research using statistical methods such as imputation of missing data is needed. Copyright © 2005 by the American Academy of Pediatrics.

Objective: To evaluate changes in obstetrical and neonatal care for very preterm and extremely preterm infants between 1983 and 1995 in The Netherlands and to evaluate the effect of those changes. Study design: Data on all very preterm or VLBW infants from the linked national obstetrical and neonatal databases of 1995 (N=2066) were compared to data on similar infants from a nation-wide study of very preterm infants born in 1983 (N=1338). Results: Obstetrical and neonatal management changed over time, with an increased number of deliveries in tertiary centres (35.7-60.7%), an increase in C-sections (43.7-56.8%) and prolonged artificial ventilation (3.4-9.5%). Survival until discharge increased from 75 to 90% and neonatal morbidity decreased in relative terms. Conclusions: The short-term outcome for these very preterm and extremely preterm infants has improved. Long-term follow-up through to school age and adulthood of preterm infants is needed to investigate the changes in the sequelae of intensive obstetrical and neonatal care. © 2003 Elsevier Ireland Ltd. All rights reserved.

According to the ICP (infancy-childhood-puberty) growth model, statural growth can be divided into three partially superimposed components assumed to represent different physiologic mechanisms. This model predicts a sudden acceleration of length velocity (LV) at the onset of the childhood component around 9 months. The existence of such an infancy-childhood growth spurt has not yet been firmly corroborated by epidemiological studies. In the present study length measurements were made at the target ages of 1, 3, 6, 9, 12, 15, 18 and 24 months in a birth cohort of 2034 infants. In order to check whether length growth showed a continuous smooth pattern, different mathematical models were fitted to the individual growth curves. The models included Count and Guo functions, 5th order polynomial and combinations of 5th order polynomial with the logarithmic term of the Count function and the square root term of the Guo function. We showed that in boys and girls there is a small but systematic lack of fit of the mathematical modeling, due to a sudden acceleration of LV around 9 months. In addition there was an increase in variation of attained length at this age. Comparison of unbalanced ANOVA models with and without addition of dummy variables for the target ages confirmed that there was an acceleration around 9 months that, if corrected for, leads to a significantly improved model fit (likelihood ratio test p<0.0001). In absolute terms of LV, the misfit at 9 months was not greater than 0.5 cm/year on average. We conclude that the results of this study support the existence of a late infancy growth spurt. In our opinion, however, the magnitude of the phenomenon does not legitimate construction and use of discontinuous growth references such as the ICP reference.

For each activity the rate is changing over time. In most inventories these data are organised in tables, providing an activity rate for each relevant activity for each time step (in most cases each year). The temporal resolution of the activity data determines also the temporal resolution of the inventory.

Bij 117 te vroeg geboren kinderen werden op de gecorrigeerde leeftijd van 2 jaar de uitkomsten van het Van Wiechen-onderzoek vergeleken met de uitkomsten van ontwikkelingsonderzoek volgens de Bayley-ontwikkelings schalen. De Spearman-correlatiecoefficient tussen de beide uitkomsten op de leeftijd van 2 jaar bedroeg 0,64. De relatie met handicap of beperking op 5-jarige leeftijd was voor het Bayley-onderzoek sterker dan voor bet Van Wiechen-onderzoek. Bij beide onderzoeken was er een goede specificiteit, met weinig overdiagnostiek, maar de sensitiviteit van beide was laag. Voor kinderen met een goed resultaat bij bet Van Wiechen-onderzoek leverde bet uitvoeren van een Bayley-test geen nieuwe gegevens. Voor kinderen met een slecht resultaat was uitgebreider onderzoek waaronder ontwikkelingspsychologisch onderzoek ook buiten de onderzoeksopzet om geindiceerd. Bij kinderen met een negatief gescoord item bij bet Van Wiechen onderzoek kon bet Bayley-onderzoek een goed onderscheid maken tussen kinderen met een hoog, respectievelijk met een laag risico op een handicap of beperking op de leeftijd van 5 jaar. Aanwijzingen voor lichte stoornissen op de leeftijd van 5 jaar, zoals lichte algemene retardatie, achterstand in spraak-taalontwikkeling, lichte neurologische dysfunctie of visusstoornissen, bleken op 2-jarige leeftijd vaak nog niet aantoonbaar ongeacht welk onderzoek werd gebruikt. Bij jonge kinderen is het Van Wie&shy;chen-onderzoek een goed hulpmiddel om te onderscheiden bij welke kinderen nader onderzoek noodzakelijk is. Om lichte ontwikkelingsstoornissen, die bij te vroeg geborenen vaak voorkomen en die een belangrijke invloed hebben op bet later functioneren op school te onderkennen is follow up zeker tot de kleuterleeftijd noodzakelijk.

In 563 surviving very preterm (<32 weeks gestational age) and/or very low birthweight (<1500 g) infants the relationship between neonatal thyroxine concentration and psychomotor development at 2 years of age (corrected for preterm birth) was studied. A significant association was found between low neonatal thyroxine concentration and a negative score on the three milestones of development. These findings do not support the view that transient hypothyroxinaemia in preterm infants is harmless. Chemicals/CAS: thyroxine, 7488-70-2; Thyroxine, 7488-70-2

Transient neonatal hypothyroxinemia is very common in preterm infants. The literature on the effect of this hypothyroxinemia is, however, controversial, and large or long-term follow-up studies are not available. In a nationwide prospective follow-up study on very preterm and (or) very low birth weight infants (n = 717), we studied the relationship between thyroxine levels in the 1st wk of life and neurodevelopmental outcome at 5 y of age and school performance at 9 y of age. Thyroxine concentrations from filter paper eluates were determined in 717 infants: 32% had levels of more than 3 SD below the mean (<60 nmol/L). The percentage of infants with such low levels increased with decreasing gestational age. At the age of 5 y, 96% of survivors (n = 640) were available for extensive neurodevelopmental examination: 85 (13.3%) had a disability and 92 (14.3%) a handicap. At the age of 9 y, 83% of survivors (n = 552) answered a questionnaire on school performance: 300 (54.3%) were in mainstream education in a grade appropriate for age, 151 (27%) were in mainstream education with grade retention, and 101 (18.3%) were in special education. Both neurologic dysfunction at age 5 y and school failure at age 9 y were significantly related to lower neonatal thyroxine levels even after adjustment for other perinatal factors (odds ratio, 1.3) Whether this relationship is causal should be investigated. If a causal relationship exists, substitution therapy may at least partially prevent neurologic dysfunction and learning disabilities, both common sequelae of very preterm birth.

Doel. Onderzoeken of de geboortegewichtscurven (‘Amsterdamse groeicurven’) van Kloosterman, gebaseerd op gegevens uit 1931-1965, voor vroeggeborenen nog steeds van toepassing zijn. Opzet. Inventariserend onderzoek. Plaats. Nederland. Methode. De gegevens werden ontleend aan het ‘project onderzoek praematuritas en small for gestational age’ (POPS), verricht in 1983. De onderzoeksgroep bestond uit 855 blanke kinderen met een zwangerschapsduur van 24-31 weken. Resultaten. De percentages kinderen ‘small for gestational age’ (SGA) waren bij vrijwel iedere zwangerschapsduur hoger dan 10, terwijl ze per definitie 10 zouden moeten bedragen; de percentages kinderen ‘large for gestational age’ (LGA) waren veel lager dan 10. Ook na uitsluiting van electieve geboorten bleven de percentages afwijkend. Conclusie. Deze verschuivingen in de verdeling van geboortegewichten zijn waarschijnlijk vooral het gevolg van veranderingen in de hedendaagse verloskunde. De geboortegewichtspercentielgrenzen zullen voor vroeggeborenen opnieuw vastgesteld moeten worden.

In a prospective collaborative survey on very preterm (less than 32 weeks) and/or very low birthweight (VLBW) infants (less than 1500 g) in The Netherlands, the use of health services was studied by examining the incidence of and reasons for rehospitalisation and the use of out-patient care, i.e. visits to medical specialists and physical therapists. Out of 1338 liveborn infants originally enrolled in the survey, 998 survived the initial hospital stay. Their use of health services was studied during four period: discharge-3 months, 3-6, 6-12 and 12-24 months corrected for expected date of delivery. A total of 320 infants (34%) was readmitted on 481 occasions. The main reasons for rehospitalisation were surgical procedures, of which inguinal herniorrhaphy was the most prominent, and respiratory tract disorders: 149 admissions (31%) and 147 (31%) admissions respectively. The remaining reasons for rehospitalisation occurred less frequently. In a multivariate analysis, both sex and the length of the initial hospital stay were shown to be significantly associated with an increased risk of rehospitalisation. During the study period, 671 children (67%) attended a medical specialist other than their paediatrician, and 313 children (31%) attended a physical therapist. The use of out-patient services was higher in the first than in the second year of follow-up. The use of health services depended very much on the neurodevelopmental status of the child. In the second year of life, a similar rehospitalisation rate and use of out-patient services was found in the non-impaired children as in children from the general Dutch population.

To assess the impact of both perinatal disorders and developmental problems identified at preschool age on school performance, we followed a virtually complete birth cohort of very premature (<32 completed weeks of gestation) and very low birth weight infants until they were 9 years of age. In 84% of the survivors (n = 813), data on school performance were available for analysis. At the age of 9 years, 19% of the children were in special education. Of the children in mainstream education, 32% were in a grade below the appropriate level for age and 38% had special assistance. After correction for other perinatal items, children of low socioeconomic status and boys had significantly higher adjusted odds ratios for special education. Logistic regression with a perinatal and a 5-year time category showed that the most predictive factors for-special education were developmental delay, neuromotor and speech/language function, inattention and hyperactivity score, total problem score, and reported school results at the age of 5 years. When children with disabilities were left out of the analysis, the importance of neuromotor function and total problem score disappeared. Increased risks of any school failure in nondisabled children included mild or severe developmental delay and marginal or poor school performance at the age of 5 years. Long-term follow-up with specific attention to these predictors at 5 years of age, although time-consuming, is necessary.

Since the introduction of neonatal intensive care in the 1960s, mortality in very preterm and very low birthweight infants has been decreasing steadily. Consequently, interest in the outcome of surviving infants is growing. Restriction of health care resources has stressed the need for information concerning the effect of individual treatment components on mortality and morbidity. Concern about the quality in apparently normal survivors has been increasing as well. The current flood of papers on these subjects illustrates the interest in these issues. The first part of this paper reviews the methodology used in follow-up studies in the past decades. It aims at methodological problems that hamper comparison between studies and preclude unequivocal conclusions. New treatment techniques seldom were but should be evaluated by randomised trials. To monitor the combined effects of changing obstetric and neonatal techniques on perinatal outcome, studies in geographically defined populations are recommended using data from early pregnancy until at least preschool age. Comparability of outcomes could be enhanced by international agreement on standardisation of assessment methods and outcome measures. In the second part the results concerning gestational age- and birthweight-specific mortality, impairments and disabilities and the risk factors for such disorders are discussed. Increased survival of even the tiniest infants is clearly established. This increase in survival has not yet been accompanied by an apparent increase in major morbidity. However, many minor impairments are reported, occurring often in combination and predisposing these children to deviations of normal development. Important changes in the manifestation of brain damage appear to occur during development. These findings stress the importance of long-term follow-up studies.

Objective: To assess social lifestyle, risk-taking behavior, and psychopathology in young adults born very preterm or with a very low birthweight. Study design: This study was part of the 19-year follow-up in a large ongoing collaborative study in the Netherlands (the POPS study) on the long-term outcome of prematurity and dysmaturity. 656 adolescents from the POPS study without serious handicap were compared with peers in the general population in lifestyle, risk-taking behavior, psychopathology, and social participation. Results: Adolescents from the POPS study smoked significantly less than their peers. Compared with their peers, boys from the POPS study consumed alcohol less often, and girls from the POPS study consumed alcohol approximately as often. Lifetime drug-use was significantly lower than in the reference group. With the exception of fare-dodging, criminal behavior in POPS adolescents was significantly lower than in control subjects. Boys had more trouble in establishing a relationship. The clinical psychopathology reported by POPS subjects was not significantly higher than in control subjects. Conclusion: Adolescents born very preterm or with a very low birthweight without serious disabilities engaged less in risk-taking behavior, did not show more psychopathology, but had more difficulties in establishing social contacts. The latter might be attributable to a more prominent internalizing behavior. © 2008 Mosby, Inc. All rights reserved.

Background: In the Netherlands, there is a very low incidence of sudden infant death syndrome (SIDS) due to effective preventive campaigns. Methods: During the period September 1996 to August 2002, nationwide 161 deaths from SIDS (about 85% of all cases of SIDS during that time) were investigated by the Cot Death Committee of the Dutch Paediatric Association. Results and Discussion: Over 10% of cases of SIDS took place during some type of child care. From a national survey carried out in 2000/01 information was available on the child care attendance of 2000 Dutch infants aged 3-6 months. Based on the hours usually spent in child care by these infants, the number of similarly aged infants that died from SIDS while attending child care was 4.2 times higher than expected. Remarkably, the prevalence of known risk factors for SIDS, such as sleeping position and parental smoking, was favourable in the SIDS cases in child care settings. The adherence of child care facilities to the safe sleeping recommendations is high in the Netherlands, and no explanation as to why child care settings may be associated with an increased risk of SIDS is apparent. The possibility of other explanations, such as stress and change in routine care, is hypothesised.