The role of a biostatistical and epidemiologic review for a clinical journal

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135200/1/ijgo91.pd

Public perceptions of endometriosis: perspectives from both genders

Objective. Many women with endometriosis experience significant delay between the onset of symptoms and definitive diagnosis. Much is published on physician awareness of endometriosis and on the experiences of women with the condition. There is a paucity of data, however, surrounding perceptions of endometriosis in the general population. This study aims to assess knowledge of endometriosis among individuals of both genders. Design. Survey study. Setting. Family waiting room of a large university hospital. Population. A total of 543 men and women. Methods. Surveys were distributed to men and women over the age of 18 in the family waiting room of a large university hospital. Main outcome measures. A series of questions regarding the etiology, symptoms, and treatments for endometriosis were combined into a composite knowledge score. Results. Knowledge of endometriosis was positively correlated with female gender, education level, regular health care, and exposure to individuals with the disease. Women diagnosed with endometriosis were more likely to have discussed symptoms of the condition with their physicians than women without the diagnosis. Conclusions. Individuals of both genders have limited knowledge of the signs and symptoms of endometriosis, which may contribute to the delay in diagnosis of the condition.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79158/1/00016341003657900.pd

Effect of prenatal EPA and DHA on maternal and umbilical cord blood cytokines

Abstract Background Investigators have hypothesized that omega-3 fatty acid supplementation may modulate the immune response. However, available evidence is conflicting. We performed this study to investigate the effect of prenatal eicosapentaenoic acid (EPA)- and docosahexaenoic acid (DHA)-rich fish oil supplementation on maternal and fetal cytokine production. Methods This study is a secondary analysis of a randomized controlled trial designed to assess whether prenatal EPA- or DHA-rich fish oil supplementation would prevent perinatal depressive symptoms among women at risk. Enrolled participants received EPA-rich fish oil (1060 mg EPA plus 274 mg DHA), DHA-rich fish oil (900 mg DHA plus 180 mg EPA) or soy oil placebo. Maternal venous blood was collected at enrollment (12–20 weeks gestation) and after supplementation (34–36 weeks gestation). Umbilical cord blood was collected at delivery. We analyzed stored plasma specimens for 16 human cytokines using multiplex immunoassays. Maternal and cord blood cytokine levels were compared among the treatment groups. Associations of serum DHA and EPA with maternal and cord blood cytokines were explored via regression analysis. Results We enrolled 126 women, of whom 118 completed the trial. Prenatal supplementation with EPA-rich fish oil significantly lowered maternal IL6, IL15, and TNFα concentrations. However, supplementation with DHA-rich fish oil had no significant effect on maternal cytokine profiles. Maternal serum DHA fraction was significantly associated with IL1α, and maternal serum DHA and EPA fractions were significantly associated with IL 10 concentrations after supplementation. Compared with placebo, supplementation with EPA- or DHA-rich fish oils had no significant effect on cord blood cytokine concentrations. Conclusions Prenatal supplementation with EPA-rich fish oil significantly reduced levels of several inflammatory cytokines in maternal plasma, while prenatal DHA-rich fish oil had no significant effect on cytokine concentrations. Supplementation with EPA- and DHA- rich fish oil had no significant effect on umbilical cord blood cytokine concentrations. Trial registration Clinical Trial Registration: registration number NCT00711971 7/7/2008.https://deepblue.lib.umich.edu/bitstream/2027.42/144528/1/12884_2018_Article_1899.pd

State-Specific Trends in Preterm Delivery: Are Rates Really Declining Among Non-Hispanic African Americans Across the United States?

Objectives : This study sought to examine state-specific trends in preterm delivery rates among non-Hispanic African Americans and to assess whether these rates are influenced by misclassification of gestational age. Methods : The sample population consisted of singleton non-Hispanic White and non-Hispanic African–American infants born in 1991 and 2001 to U.S. resident mothers. For both time periods, state-specific and national preterm delivery rates were calculated for all infants, stratified by infant race/ethnicity. Next, birth-weight distributions within strata of gestational age were studied to explore possible misclassifications of gestational age. Lastly, state-specific and national preterm delivery rates among infants who weighed less than 2,500 g were separately computed. Results: National analyses showed that the frequency of preterm delivery increased by 15.8% among non-Hispanic Whites but declined by 10.3% among non-Hispanic African Americans over the same period. For both subgroups, a bimodal distribution of birth weights was apparent among preterm births at 28–31 weeks of gestation. The second peak with its cluster of normal-weight infants was more prominent among non-Hispanic African Americans in 1991 than in 2001. After excluding preterm infants who weighed 2,500 g or more, the national trends persisted. State-specific analyses showed that preterm delivery rates increased for both subgroups in 13 states during this period. Of these 13, 6 states had a number of non-Hispanic African–American births classified as preterm that were apparently term births mistakenly assigned short gestational ages. Such misclassification was more frequent in 1991 than in 2001 and inflated 1991 rates. Conclusion : There is heterogeneity in state-specific preterm delivery rates. Such differences are often overlooked when aggregate results are presented.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45321/1/10995_2005_Article_32.pd

Vitamin D levels and perinatal depressive symptoms in women at risk: a secondary analysis of the mothers, omega-3, and mental health study

Abstract Background Vitamin D insufficiency may be associated with depressive symptoms in non-pregnant adults. We performed this study to evaluate whether low maternal vitamin D levels are associated with depressive symptoms in pregnancy. Methods This study was a secondary analysis of a randomized trial designed to assess whether prenatal omega-3 fatty acid supplementation would prevent depressive symptoms. Pregnant women from Michigan who were at risk for depression based on Edinburgh Postnatal Depression Scale Score or history of depression were enrolled. Participants completed the Beck Depression Inventory (BDI) and Mini International Neuropsychiatric Interview at 12–20 weeks, 26–28 weeks, 34–36 weeks, and 6–8 weeks postpartum. Vitamin D levels were measured at 12–20 weeks (N = 117) and 34–36 weeks (N = 112). Complete datasets were available on 105 subjects. Using regression analyses, we evaluated the relationship between vitamin D levels with BDI scores as well as with MINI diagnoses of major depressive disorder and generalized anxiety disorder. Our primary outcome measure was the association of maternal vitamin D levels with BDI scores during early and late pregnancy and postpartum. Results We found that vitamin D levels at 12–20 weeks were inversely associated with BDI scores both at 12—20 and at 34–36 weeks’ gestation (P < 0.05, both). For every one unit increase in vitamin D in early pregnancy, the average decrease in the mean BDI score was .14 units. Vitamin D levels were not associated with diagnoses of major depressive disorder or generalized anxiety disorder. Conclusions In women at risk for depression, early pregnancy low vitamin D levels are associated with higher depressive symptom scores in early and late pregnancy. Future investigations should study whether vitamin D supplementation in early pregnancy may prevent perinatal depressive symptoms. Trial registration https://clinicaltrials.gov/ Registration Number: NCT00711971http://deepblue.lib.umich.edu/bitstream/2027.42/134615/1/12884_2016_Article_988.pd

The mothers, Omega-3 and mental health study

<p>Abstract</p> <p>Background</p> <p>Major depressive disorder (MDD) during pregnancy and postpartum depression are associated with significant maternal and neonatal morbidity. While antidepressants are readily used in pregnancy, studies have raised concerns regarding neurobehavioral outcomes in exposed infants. Omega-3 fatty acid supplementation, most frequently from fish oil, has emerged as a possible treatment or prevention strategy for MDD in non-pregnant individuals, and may have beneficial effects in pregnant women. Although published observational studies in the psychiatric literature suggest that maternal docosahexaenoic acid (DHA) deficiency may lead to the development of MDD in pregnancy and postpartum, there are more intervention trials suggesting clinical benefit for supplementation with eicosapentaenoic acid (EPA) in MDD.</p> <p>Methods/Design</p> <p>The Mothers, Omega-3 and Mental Health study is a double blind, placebo-controlled, randomized controlled trial to assess whether omega-3 fatty acid supplementation may prevent antenatal and postpartum depressive symptoms among pregnant women at risk for depression. We plan to recruit 126 pregnant women at less than 20 weeks gestation from prenatal clinics at two health systems in Ann Arbor, Michigan and the surrounding communities. We will follow them prospectively over the course of their pregnancies and up to 6 weeks postpartum. Enrolled participants will be randomized to one of three groups: a) EPA-rich fish oil supplement (1060 mg EPA plus 274 mg DHA) b) DHA-rich fish oil supplement (900 mg DHA plus 180 mg EPA; or c) a placebo. The primary outcome for this study is the Beck Depression Inventory (BDI) score at 6 weeks postpartum. We will need to randomize 126 women to have 80% power to detect a 50% reduction in participants' mean BDI scores with EPA or DHA supplementation compared with placebo. We will also gather information on secondary outcome measures which will include: omega-3 fatty acid concentrations in maternal plasma and cord blood, pro-inflammatory cytokine levels (IL-1β, IL-6, and TNF-α) in maternal and cord blood, need for and dosage of antidepressant medications, and obstetrical outcomes. Analyses will be by intent to treat.</p> <p>Discussion</p> <p>This study compares the relative effectiveness of DHA and EPA at preventing depressive symptoms among pregnant women at risk.</p> <p>Trial registration</p> <p>Clinical trial registration number: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00981877">NCT00711971</a></p

Model Averaging for Improving Inference from Causal Diagrams

Model selection is an integral, yet contentious, component of epidemiologic research. Unfortunately, there remains no consensus on how to identify a single, best model among multiple candidate models. Researchers may be prone to selecting the model that best supports their a priori, preferred result; a phenomenon referred to as “wish bias”. Directed acyclic graphs (DAGs), based on background causal and substantive knowledge, are a useful tool for specifying a subset of adjustment variables to obtain a causal effect estimate. In many cases, however, a DAG will support multiple, sufficient or minimally-sufficient adjustment sets. Even though all of these may theoretically produce unbiased effect estimates they may, in practice, yield somewhat distinct values, and the need to select between these models once again makes the research enterprise vulnerable to wish bias. In this work, we suggest combining adjustment sets with model averaging techniques to obtain causal estimates based on multiple, theoretically-unbiased models. We use three techniques for averaging the results among multiple candidate models: information criteria weighting, inverse variance weighting, and bootstrapping. We illustrate these approaches with an example from the Pregnancy, Infection, and Nutrition (PIN) study. We show that each averaging technique returns similar, model averaged causal estimates. An a priori strategy of model averaging provides a means of integrating uncertainty in selection among candidate, causal models, while also avoiding the temptation to report the most attractive estimate from a suite of equally valid alternatives

College Students' Perceptions of Emergency Contraception Provision

ABSTRACT Background and objective: The authors examined college students' perceptions regarding emergency contraception (EC) provision in light of the then pending U.S. Food and Drug Administration (FDA) decision about the over-the-counter (OTC) status of EC. Methods: We randomly sampled 7000 male and female students who were enrolled full-time at the University of Michigan during the winter 2006 semester. A total of 1585 (22.6%) students responded to our web-based survey and were included in these descriptive analyses. Results: Nearly all (94%) respondents knew of EC. When asked whether EC should be made available OTC, 60% of respondents agreed, 23% disagreed, and 17% were unsure. If EC were to be made available OTC, 34% of respondents indicated that they (or their partner) would purchase EC in advance of need, and 44% stated that they would purchase it only after unprotected sexual intercourse or contraceptive failure. Advance discussion and provision of EC is underused. Only 10% of all female respondents indicated that their current healthcare provider had spoken to them about EC in a routine health visit, and just 5% of female respondents were offered a supply of EC in advance of need. Conclusions: Continued efforts are needed to ensure timely access to EC in this population.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63435/1/jwh.2007.0391.pd