Negative Test Patients Research Articles

The assessment of patients undergoing cardiac surgery for Covid-19: Complications occurring during cardiopulmonary bypass.

The outbreak of the novel coronavirus pandemic (COVID-19) has resulted in dramatic changes to the conduct of surgery both from a patient management perspective and in protecting healthcare providers. The current study reports on the status of COVID-19 infections in patients presenting for cardiac surgery with cardiopulmonary bypass (CPB) on circuit complications. A tracking process for monitoring the presence of COVID-19 in adult cardiac surgery patients was integrated into a case documentation system across United States hospitals where out-sourced perfusion services were provided. Assessment included infection status, testing technique employed, surgery status and CPB complications. Records from 5612 adult patients who underwent cardiac surgery between November 1, 2020 and January 18, 2021 from 176 hospitals were reviewed. A sub-cohort of coronary artery bypass graft patients (3283) was compared using a mixed effect binary logistic regression analysis. 4297 patients had negative test results (76.6%) while 49 (0.9%) tested positive for COVID-19, and unknown or no results were reported in 693 (12.4%) and 573 (10.2%) respectively. Coagulation complications were reported at 0.2% in the negative test results group versus 4.1% in the positive test result group (p < 0.001). Oxygenator gas exchange complications were 0.2% in the negative test results group versus 2.0% in the positive test results group (p = 0.088). Coronary artery bypass graft patients with a positive test had significantly higher risk for any CPB complication (p = 0.003) [OR 10.38, CI 2.18–49.53] then negative test patients [OR 0.01, CI 0.00–0.20]. The present study has shown that patients undergoing cardiac surgery with CPB who test positive for COVID-19 have higher CPB complication rate than those who test negative.

Using Relative Statistics and Approximate Disease Prevalence to Compare Screening Tests.

Schatzkin et al. and other authors demonstrated that the ratios of some conditional statistics such as the true positive fraction are equal to the ratios of unconditional statistics, such as disease detection rates, and therefore we can calculate these ratios between two screening tests on the same population even if negative test patients are not followed with a reference procedure and the true and false negative rates are unknown. We demonstrate that this same property applies to an expected utility metric. We also demonstrate that while simple estimates of relative specificities and relative areas under ROC curves (AUC) do depend on the unknown negative rates, we can write these ratios in terms of disease prevalence, and the dependence of these ratios on a posited prevalence is often weak particularly if that prevalence is small or the performance of the two screening tests is similar. Therefore we can estimate relative specificity or AUC with little loss of accuracy, if we use an approximate value of disease prevalence.

Fructose Malabsorption in Patients With Irritable Bowel Syndrome-like Symptoms: What Is the Role in the Pathogenesis and Clinical Implication?

Article: Unclear abdominal discomfort: pivotal role of carbohydrate malabsorption Goebel-Stengel M, Stengel A, Schmidtmann M, van der Voort I, Kobelt P, Mönnikes H.

Differential characteristics of adolescent pregnancy test patients: Abortion, childbearing test groups

Studies of the consequences of adolescent childbearing report many negative sequelae, but the effects of induced abortion are less studied, and most studies lack appropriate controls for preexisting characteristics. This paper uses baseline data from the intake interview into a longitudinal study of 360 innercity black women (≤17 years old) presenting for a pregnancy test at two sites in Baltimore to examine baseline differences between three groups: young women who terminated the index pregnancy and, as controls, those who carried to term and those whose tests were negative. They were interviewed before being told the test result. Education aspirations/ achievement, economic well-being, sexual/contraceptive history, psychologic characteristics, and desire for a child were compared. Negative test patients often reveal characteristics suggesting a particularly high risk of pregnancy, e.g., more prior pregnancy tests and a greater desire to conceive. Implications are discussed, emphasizing the need to intervene after a negative pregnancy test with counseling to help avert a future undesired conception.