Inclusion of binary proxy variables in logistic regression improves treatment effect estimation in observational studies in the presence of binary unmeasured confounding variables.

We present a simulation study and application that shows inclusion of binary proxy variables related to binary unmeasured confounders improves the estimate of a related treatment effect in binary logistic regression. The simulation study included 60,000 randomly generated parameter scenarios of sample size 10,000 across six different simulation structures. We assessed bias by comparing the probability of finding the expected treatment effect relative to the modeled treatment effect with and without the proxy variable. Inclusion of a proxy variable in the logistic regression model significantly reduced the bias of the treatment or exposure effect when compared to logistic regression without the proxy variable. Including proxy variables in the logistic regression model improves the estimation of the treatment effect at weak, moderate, and strong association with unmeasured confounders and the outcome, treatment, or proxy variables. Comparative advantages held for weakly and strongly collapsible situations, as the number of unmeasured confounders increased, and as the number of proxy variables adjusted for increased.

The effects of maternal hypertension on the early neonatal platelet count.

OBJECTIVE: To examine the relationship between maternal hypertension and early neonatal platelet counts. STUDY DESIGN: This single site retrospective cohort study compared initial platelet counts in the first day of life of infants born to mothers with preeclampsia with severe features (PSF) (n = 224) and infants born to normotensive mothers using multivariable logistic and Quasi-Poisson regression models. RESULT: There was no statistical difference in initial platelet counts or likelihood of thrombocytopenia (aOR = 1.19, 95% CI 0.68-2.08) between infants born to mothers with PSF and infants born to normotensive mothers after multivariable adjustment. Initial platelet counts and thrombocytopenia risk were unaffected by the presence of maternal end organ dysfunction. Small for gestational age (SGA) status was the most significant risk factor for the development of thrombocytopenia (aOR = 2.24, 95% CI 1.13-4.30). CONCLUSION: Maternal PSF does not directly affect neonatal initial platelet counts. SGA status confers the greatest risk of early thrombocytopenia.

Long-term impact of a single interprofessional education high-fidelity simulation experience: a pilot study.

The interprofessional education (IPE) simulation literature lacks research assessing long-term IPE outcomes. During the 2018-19 and 2019-20 academic year, third year and fourth year medical students, respectively, engaged in an IPE simulation experience focused on cardiopulmonary resuscitation. Students completed the Interprofessional Collaborative Competencies Attainment Survey. There was a statistically significant positive change (p<0.05) in student perceptions of their interprofessional collaborative skills immediately following a single IPE simulation activity for both third and fourth year students. However, a statistically significant decline in means was noted from third year post-questions to fourth year pre-questions. A single annual IPE simulation activity may not be sufficient to support students in building confidence in their collaborative skills without regression.