Jane C. Bell

The accuracy of reporting of the hypertensive disorders of pregnancy in population health data.

Objective. To assess the accuracy of hypertensive disorders of pregnancy reporting in birth and hospital discharge data compared with data abstracted from medical records. Methods. Data from a validation study of 1200 women provided the ‘gold standard’ for hypertension status. The validation data were linked to both hospital discharge and birth databases. Hypertension could be reported in one, both, or neither database. Results. Of the 1184 records available for review, 8.3% of women had pregnancy-related hypertension and 1.3% had chronic hypertension. Reporting sensitivities ranged from 23% to 99% and specificities from 96% to 100%. Using broad rather than specific categories of hypertension and more than one source to identify hypertension improved case ascertainment. Women with severe preeclampsia or adverse outcomes were more likely to have their pregnancy-related hypertension reported. When the hypertension reporting was discordant on the birth and hospital discharge data, the hospital data were more accurate. Conclusions. Pregnancy-related hypertension is reported with a reasonable level of accuracy, but chronic hypertension is markedly under-ascertained, even when cases were identified from more than one source. Milder forms of hypertension are more likely to go unreported. Studies utilizing population health data may overestimate the proportion of more severe forms of disease and any risk these conditions contribute to other outcomes.

Measuring maternal morbidity in routinely collected health data: development and validation of a maternal morbidity outcome indicator.

Background:As maternal deaths become rare in many countries, severe maternal morbidity has been suggested as a better indicator of quality of care. Objective:To develop and validate an indicator for measuring major maternal morbidity in routinely collected population health datasets (PHDS). Methods:First, diagnoses and procedures that might indicate major maternal morbidity were compiled and used to sample possible cases in PHDS; second, a validation study of indicated cases was undertaken by review of birth admission medical records using a nested case-control study approach with 400 possible cases and 800 controls; finally “true” morbidity from the validation study was used to define a maternal morbidity outcome indicator (MMOI) with a high positive predictive value (PPV). Sensitivity, specificity, PPV, negative predictive value (NPV), and exact 95% confidence intervals (95% CI) were weighted by the sampling probabilities. Results:There were 1184 records available for review. Of 393 possible cases only 188 were confirmed as suffering major morbidity (weighted PPV 47.3%, sensitivity 72.9%) and of the 791 initial noncases, 787 were confirmed as noncases (weighted NPV 99.5%, specificity 98.5%). Revision of the initial indicator with exclusion of noncontributing International Classification of Disease (ICD) codes provided a MMOI with population-weighted rate of 1.5%, PPV 94.6% (95% CI: 72.3–99.9), sensitivity 78.4% (95% CI: 55.2–93.1), specificity 99.9% (95% CI: 99.5–99.9), and 99.5% agreement with “true” morbidity (kappa 0.86). Conclusions:PHDS can be used reliably to identify women who suffer a major adverse outcome during the birth admission and have potential for monitoring the quality of obstetric care in a uniform and cost-effective way.

Outcomes of pregnancies in women with pre-gestational diabetes mellitus and gestational diabetes mellitus; a population-based study in New South Wales, Australia, 1998–2002

Aim  To determine population‐based rates and outcomes of pre‐gestational diabetes mellitus (pre‐GDM) and gestational diabetes mellitus (GDM) in pregnancy.

How accurate is the reporting of obstetric haemorrhage in hospital discharge data? A validation study.

Background: Routinely collected datasets are frequently used for population‐based research but their accuracy needs to be assured.

Trends in adverse maternal outcomes during childbirth: a population-based study of severe maternal morbidity

BackgroundMaternal mortality is too rare in high income countries to be used as a marker of the quality of maternity care. Consequently severe maternal morbidity has been suggested as a better indicator. Using the maternal morbidity outcome indicator (MMOI) developed and validated for use in routinely collected population health data, we aimed to determine trends in severe adverse maternal outcomes during the birth admission and in particular to examine the contribution of postpartum haemorrhage (PPH).MethodsWe applied the MMOI to the linked birth-hospital discharge records for all women who gave birth in New South Wales, Australia from 1999 to 2004 and determined rates of severe adverse maternal outcomes. We used frequency distributions and contingency table analyses to examine the association between adverse outcomes and maternal, pregnancy and birth characteristics, among all women and among only those with PPH. Using logistic regression, we modelled the effects of these characteristics on adverse maternal outcomes. The impact of adverse outcomes on duration of hospital admission was also examined.ResultsOf 500,603 women with linked birth and hospital records, 6242 (12.5 per 1,000) suffered an adverse outcome, including 22 who died. The rate of adverse maternal outcomes increased from 11.5 in 1999 to 13.8 per 1000 deliveries in 2004, an annual increase of 3.8% (95%CI 2.3–5.3%). This increase occurred almost entirely among women with a PPH. Changes in pregnancy and birth factors during the study period did not account for increases in adverse outcomes either overall, or among the subgroup of women with PPH. Among women with severe adverse outcomes there was a 12% decrease in hospital days over the study period, whereas women with no severe adverse outcome occupied 23% fewer hospital days in 2004 than in 1999.ConclusionSevere adverse maternal outcomes associated with childbirth have increased in Australia and the increase was entirely among women who experienced a PPH. Reducing or stabilising PPH rates would halt the increase in adverse maternal outcomes.

The prevalence of maternal medical conditions during pregnancy and a validation of their reporting in hospital discharge data.

Population health datasets are a valuable resource for studying maternal and obstetric health outcomes. However, their validity has not been thoroughly examined. We compared medical records from a random selection of New South Wales (NSW) women who gave birth in a NSW hospital in 2002 with coded hospital discharge records. We estimated the population prevalence of maternal medical conditions during pregnancy and found a tendency towards underreporting although specificities were high, indicating that false positives were uncommon.

Getting an evidence‐based post‐partum haemorrhage policy into practice

Background:  Post‐partum haemorrhage (PPH) is a potentially life‐threatening complication of childbirth occurring in up to 10% of births. The NSW Department of Health (DoH) issued a new evidence‐based policy (Framework for Prevention, Early Recognition and Management of Post‐partum Haemorrhage) in November 2002. Feedback from maternity units indicated that there were deficiencies in the skills and experience is needed to develop the written protocols and local plans of action required by the Framework.

Descriptive epidemiology of cleft lip and cleft palate in Western Australia

BACKGROUND The reported birth prevalence of orofacial clefts (OFCs) varies considerably. This study describes the epidemiology of OFCs in an Australian population. METHODS We studied infants diagnosed with cleft lip, with or without cleft palate (CL±P), and cleft palate only (CPO) since 1980 and reported to the population based Western Australian Register of Developmental Anomalies. We calculated prevalence rates by sex, Aboriginal status, geographic location, and socio-economic status. Associations between clefts and folate availability, pregnancy characteristics, pregnancy outcomes, other congenital anomalies, and age at diagnosis were also investigated. RESULTS From 1980 to 2009, 917 infants with CL±P (12.05 per 10,000) and from 1980 to 2004, 621 infants with CPO (10.12 per 10,000) were registered. Prevalence rates for CL±P and CPO were 1.9 and 1.3 times higher, respectively, for Aboriginal Australians. Additional anomalies were reported for 31% of infants with CL±P and for 61% with CPO; chromosomal anomalies and other specific diagnoses accounted for 46% and 66%, respectively, of those with CL±P and CPO with additional anomalies. Almost all (99.7%) children with CL±P were diagnosed before 1 year of age, but 12% of CPO diagnoses were made after 1 year of age; 94% of these diagnoses were of submucous clefts and bifid uvula. CONCLUSIONS These data provide a picture of the prevalence of OFCs in WA since 1980, and provide a useful reference for OFC data in Australia and internationally. The quality and completeness of the WARDA data are high, reflected in high prevalence rates, and proportions of clefts occurring with other anomalies.

Demographic and socio-economic factors associated with dental health among older people in NSW

Objective: To investigate the association between oral health status and social, economic and demographic factors in community‐dwelling older people in New South Wales (NSW).

Maternal alcohol consumption during pregnancy and the risk of orofacial clefts in Infants: A Systematic Review and Meta-Analysis

BACKGROUND The teratogenic effects of maternal alcohol consumption during pregnancy include anomalies of craniofacial structures derived from the cranial neural crest cells. The presence of specific craniofacial anomalies contributes to the diagnosis of fetal alcohol spectrum disorders. Cleft lip and palate [orofacial clefts (OFCs)], also derived from the cranial neural crest cells, are common congenital anomalies, but their relationship with prenatal alcohol consumption is unknown. METHODS To evaluate the association between maternal consumption of alcohol during pregnancy and the occurrence of OFCs in infants, we conducted a systematic review and meta-analyses of published studies. We examined the associations between any alcohol consumption, binge level drinking, and heavy and moderate levels of consumption vs. no or low levels of consumption. RESULTS After screening 737 publications, we identified 33 studies (23 case-control and 10 cohort studies). There was considerable heterogeneity in individual study design, quality measures and study results. Findings from random effects meta-analyses suggest no relationship between prenatal alcohol consumption and the occurrence of OFCs {pooled odds ratios for any alcohol intake and binge level drinking respectively: cleft lip with or without cleft palate 1.00 [95% confidence interval (CI) 0.86, 1.16] from 18,349 participants in 13 studies, 1.04 [95% CI 0.87, 1.24] [8763 individuals, 4 studies]; cleft palate only 1.05 [95% CI 0.92, 1.21] [21,459 individuals, 17 studies], 0.94 [95% CI 0.74, 1.21] [7730 participants, 4 studies]}. CONCLUSIONS While we found no association between alcohol consumption during pregnancy and OFCs in infants, the influence of study design, particularly in relation to alcohol exposure measurement and OFC ascertainment cannot be ignored.