ISSN:0269-5022    

DOI:10.1111/j.1365-3016.1995.tb00126.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0269-5022    

DOI:10.1111/j.1365-3016.1995.tb00127.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0269-5022    

DOI:10.1111/j.1365-3016.1995.tb00128.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Summary.In order to examine neurological outcome in twins, a multicentre prospective cohort study of infants was used. Women entered at the first prenatal visit, with follow‐up of offspring to the age of 7 years. Outcome measures were death, cerebral palsy, seizure disorders including neonatal, febrile or nonfebrile, and intelligence quotient. Among a total of 52364 livebirths, there were 1079 twins. Overall, rates of fetal or neonatal death and cerebral palsy were higher in twins. Neonatal and febrile seizures occurred with similar frequency in twins as in singletons. Although twins were much more likely than singletons to be low in birthweight, twins<2500 g were not at higher risk for cerebral palsy than low birthweight singletons. The risk of cerebral palsy and of nonfebrile seizure disorders was similar in monozygous and dizygous pairs, and in like‐sex and unlike‐sex pairs. Death of one twin was associated with higher rates of cerebral palsy and of nonfebrile seizure disorders in survivors, but not with lowered intelligence. Data from this cohort suggest that low birthweight and survival status of the co‐twin are dominant predictors of childhood neurological morbidity i

ISSN:0269-5022    

DOI:10.1111/j.1365-3016.1995.tb00129.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Summary.The overall rate of cerebral palsy excluding post‐neonatal cases, has remained relatively constant, varying between 1.93 and 2.27 per 1000 births over the 20‐year period between 1969 and 1988 in Avon. The rate of the subgroup of spastic cerebral palsy varied from 1.40 to 1.78 per 1000 births over the same time period.In singletons the corresponding figures were 1.80‐2.17 per 1000 births and 1.28‐1.67 per 1000 births, and in multiple births the figures were 7.12‐8.80 per 1000 births and 7.12‐8.44 per 1000 births. Although the overall rates have remained fairly constant there was an increase in incidence in the later years among children with low birthweight and shor

ISSN:0269-5022    

DOI:10.1111/j.1365-3016.1995.tb00130.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Summary.In a geographically‐based study, we investigated the risk of cerebral palsy following intrapartum asphyxia at term, and the contribution of intrapartum asphyxia at term to the overall rate of cerebral palsy. We used stringent criteria for identifying intrapartum asphyxia, while recognising that the initial hypoxial insult might have occurred in the antenatal period.In the first part of the investigation, a cohort of 160 term, singleton infants, with a low (≤ 3) 1‐minute Apgar score, was followed to the age of 5 years. Six infants in the cohort had presumed intrapartum asphyxia, of whom two died in the neonatal period, three had spastic quadriparesis, profound developmental delay and visual impairment, and one was unimpaired. The frequency of cerebral palsy associated with birth asphyxia was estimated as one in 3700 full‐term livebirths.To assess the impact of birth asphyxia on the overall rate of cerebral palsy, all cases of cerebral palsy born in the study period were identified. Of the 30 cases, the three identified in the follow‐up study were the only ones whose impairment could be attributed to birth asphyxia in a full‐term birth. Birth asphyxia at term therefore was associated with 10% [95% confidence interval (CI) 2.1,26.5] of all cases of cerebral palsy and with 20% (95% CI 4.3,48.1) of the 15 cases of cerebral palsy in children b

ISSN:0269-5022    

DOI:10.1111/j.1365-3016.1995.tb00131.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Summary.Aetiological relationships between cerebral palsy, preterm birth, small‐for‐gestational‐age (SGA) birth and selected feto‐maternal factors were investigated in a case‐control study of all moderate and severe cerebral palsy cases born in Western Australia between 1980 and 1986 (n= 215). Cases were individually matched to three controls of the same gender and plurality born in the same year. Two of the controls were matched to the index cases for gestational age, one of which was also matched for birthweight.Pre‐eclampsia and urinary tract infections were not significantly associated with cerebral palsy. The significant association of antepartum haemorrhage with cerebral palsy was accounted for by its associations with preterm birth. Congenital malformations and non‐cerebral palsy neurological disorder were significantly associated with cerebral palsy; these associations were only partially accounted for by adjusting for preterm birth and small‐for‐gestational‐age birth.This study shows that some of the risk of cerebral palsy associated with the antenatal antecedents of some common feto‐maternal factors is mediated through preterm birth, confirming the importance of interrelationships between antenatal antecedents in the aetiology of some cerebral palsy.Perinatal and post‐neonatal causes now account for only around 20% of all cerebral palsy. Future reductions in cerebral palsy incidence may therefore depend on acquiring greater knowledge of inter‐relationships betw

ISSN:0269-5022    

DOI:10.1111/j.1365-3016.1995.tb00132.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Summary.Two studies were conducted during 1989‐90 in Central Sudan to determine the incidence of low birthweight and to ascertain the major risk factors which influence birthweight. In a hospital‐based investigation, surveillance of all births was accompanied by a nested case‐control study, and in a community based investigation, all midwife‐assisted births were studied. There were 4868 and 1523 livebirths among the hospital and community populations, respectively. The incidence of low birthweight was 18.1% in the community and 8.2% in the hospitals. The ratio of term to pre‐term low birthweight was 2.9 in the community but only 1.3 in the hospitals. Several risk factors showed consistent and significant associations with low birthweight in the hospital and community studies. Two important and modifiable predictors of term and preterm low birthweight were low maternal weight and malaria infection during pregnancy. Other risk factors included low socio‐economic status and, among the hospital population, lack of antenatal care, short birth intervals, poor obstetric history and complications o

ISSN:0269-5022    

DOI:10.1111/j.1365-3016.1995.tb00133.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

ISSN:0269-5022    

DOI:10.1111/j.1365-3016.1995.tb00134.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Summary.The underlying objective of epidemiological investigations is to extrapolate results from a sample to the relevant population. The simplest way of achieving this is to adopt a sampling strategy in which each individual in the population has the same chance of being selected ‐that is, to employ an ‘equal probability of selection method’ (epsem). The easiest ways of achieving this are to use simple random sampling or stratified random sampling with a constant sampling fraction. These strategies are often impracticable, however, particularly in large investigations covering a wide geographical area where resource implications dictate a more complex approach such as multi‐stage or cluster sampling. Following detailed definitions and appropriate illustrations of these terms, the main purpose of this paper is to provide a working guide of how to achieve epsem using these various random sampling techniques. In brief, for multi‐stage sampling with the rare feature of equal‐sized first stage units, epsem is achieved by applying the above simple or stratified approaches to the first stage units. Even in the more realistic scenario of unequal first stage units, the same options apply provided that a fixed proportion of second stage units are to be selected (cluster sampling is in fact just one example of this, with 100% sampling of second stage units). If on the other hand a fixed number of second stage units are to be selected then for epsem the first stage units should be selected with each one having a probability proportionate

ISSN:0269-5022    

DOI:10.1111/j.1365-3016.1995.tb00135.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY