Cognitive development following ART: effect of choice of comparison group, confounding and mediating factors

BACKGROUND: Epidemiological studies have examined the health of children born after assisted reproductive technology (ART), with contradictory results. In this article, we address the question 'Do singletons born after ART have a poorer cognitive developmental outcome at 3 years of age?' We assess the implications of using different comparison groups, and discuss appropriate analytical approaches for the control of confounding and mediating variables. METHODS: Data were drawn from the Millennium Cohort Study. Interviews captured sociodemographic, behavioural and pregnancy information. Developmental assessments conducted at age three included the British Ability Scales II Naming Vocabulary (BAS-NV) instrument. We compared ART infants (born after IVF or ICSI) to four comparison groups: a 'matched' group; a 'subfertile' group (time to conception >12 months); a 'fertile' group (time to conception <12 months); and an 'any spontaneous conceptions' group. Linear regression provided estimates of the difference in mean BAS-NV scores in the ART and comparison groups; both unadjusted estimates and those adjusted for confounding and mediating factors are presented. RESULTS: In the unadjusted analyses, ART children gained significantly better BAS-NV test results than did the comparison group children. When converted to an estimate of developmental age gap, ART children were 2.5, 2.7, 3.6 and 4.5 months ahead of the 'matched', 'subfertile', 'fertile' and 'spontaneous conception' children, respectively. After adjusting for confounding and mediating factors, the differences were reduced, and were not statistically significant. CONCLUSIONS: ART is not associated with poorer cognitive development at 3 years. We have highlighted methodological considerations for researchers planning to study the effect of infertility and ART on childhood outcomes

Eclampsia, a comparison within the International Network of Obstetric Survey Systems

OBJECTIVE: To compare incidences, characteristics, management and outcome of eclampsia in the Netherlands and the UK. DESIGN: A comparative analysis of two population-based prospective cohort studies. SETTING: All hospitals with consultant-led maternity units. POPULATION: Women with eclampsia in the Netherlands (226) and the UK (264). METHODS: Comparison of individual level data from national studies in the Netherlands and the UK (LEMMoN 2004-06; UKOSS 2005/06). MAIN OUTCOME MEASURES: Incidence, maternal complications and differences in management strategies. RESULTS: Incidences of eclampsia differed significantly between both countries: the Netherlands 5.4/10,000 deliveries versus UK 2.7/10,000 (relative risk [RR] 1.94, 95% confidence intervals [95% CI] 1.6-2.4). The proportion of women with a preceding diagnosis of pre-eclampsia was comparable between both countries (the Netherlands 42%; UK 43%), as was the proportion who received magnesium sulphate prophylaxis. Women in the Netherlands had a significantly higher maximum diastolic blood pressure (111 mmHg versus 95 mmHg, P < 0.001); significantly fewer received anti-hypertensive medication (16% versus 71%; RR 0.2, 95% CI 0.1-0.3) and were treated less often with magnesium sulphate after their first fit (95% versus 99%; RR 0.96, 95% CI 0.92-0.99). Maternal death occurred in three cases in the Netherlands compared with zero in the UK. CONCLUSIONS: The incidence of eclampsia in the Netherlands was twice as high compared with the UK when using uniform definitions. Women with eclampsia in the Netherlands were not managed according to guidelines, particularly with respect to blood pressure management. Changes in management practice may reduce both incidence and poor outcomes

Eclampsia, a comparison within the International Network of Obstetric Survey Systems

Obstetric

NETS(1HD) study: development of a Hirschsprung's disease core outcome set

OBJECTIVE: The objective of this study was to develop a Hirschsprung's disease (HD) core outcome set (COS). METHODS: Candidate outcomes were identified from a systematic review and stakeholder nomination. A three-phase Delphi process and consensus meeting were used to prioritise candidate outcomes based on scores assigned by stakeholder participants using a nine-point scale. In phases two and three, participants were shown graphical representations of their panel's scores and all panels' scores respectively for each outcome from the previous phase. After the third phase, outcomes prioritised by two or three panels were taken forward to the consensus meeting. The COS was formed from the 10 highest scoring outcomes meeting the threshold for inclusion (>/=70% 7-9 and need for a permanent stoma, (10) enterocolitis. CONCLUSIONS: This HD COS is formed of 10 outcomes deemed important by key stakeholders. Use of this COS in research will reduce outcome reporting heterogeneity and increase our ability to identify gold standard treatments for HD