Statin use and its association with all-cause mortality and incident diabetes/prediabetes in African Americans: Findings from the jackson heart study.

Objectives: This study investigates the association between statin use and all-cause mortality, as well as the association between statin use and incident diabetes or prediabetes among African Americans.

Methods: This study is based on the Jackson Heart Study (JHS), a community-based cohort study of African Americans (AAs). The baseline period for JHS was 9/26/2000 to 3/31/2004.

The Association Between Vitamin D Deficiency and Diabetes in Adult African Americans and Whites: An NHANES Study.

Objective: The primary objective of this cross-sectional study is to investigate the association between vitamin D deficiency (VDD) and diabetes and see if this association is the same for adult (age ≥ 20) African Americans (AAs) and Whites. The secondary objective is to examine the distribution of the 25-hydroxyvitamin D test among AAs and Whites and to evaluate the appropriateness of using the same cut-off point for both groups to diagnose VDD.

Methods: Our analysis is based on the 2011-2014 National Health and Nutrition Examination Surveys (NHANES).

Bias due to composite reference standards in diagnostic accuracy studies.

Composite reference standards (CRSs) have been advocated in diagnostic accuracy studies in the absence of a perfect reference standard. The rationale is that combining results of multiple imperfect tests leads to a more accurate reference than any one test in isolation. Focusing on a CRS that classifies subjects as disease positive if at least one component test is positive, we derive algebraic expressions for sensitivity and specificity of this CRS, sensitivity and specificity of a new (index) test compared with this CRS, as well as the CRS-based prevalence.

Evaluation of screening tests for detecting Chlamydia trachomatis: bias associated with the patient-infected-status algorithm.

In recent years, the evaluation of nucleic acid amplification tests (NAATs) for detecting Chlamydia trachomatis and Neisseria gonorrhea is based on a methodology called the patient-infected-status algorithm (PISA). In the simplest version of PISA, 4 test-specimen combinations (comparator tests) are used to define the gold standard. If a person shows a positive result by any 2 or more of these 4 comparator tests, the person is classified as infected; otherwise, the person is considered to be uninfected.

Modeling conditional dependence between diagnostic tests: a multiple latent variable model.

Applications of latent class analysis in diagnostic test studies have assumed that all tests are measuring a common binary latent variable, the true disease status. In this article we describe a new approach that recognizes that tests based on different biological phenomena measure different latent variables, which in turn measure the latent true disease status. This allows for adjustment of conditional dependence between tests within disease categories.

WITHDRAWN: Problems associated with reproducibility, validity and confirmation of nucleic acid amplification tests for detecting Chlamydia trachomatis.

This article has been withdrawn.

Evaluation of nucleic acid amplification tests in the absence of a perfect gold-standard test: a review of the statistical and epidemiologic issues.

During the past 10 years, medical diagnostic testing for sexually transmitted infections (STIs) has changed markedly as a result of the rapid expansion and marketing of nucleic acid amplification tests (NAATs). Among such new DNA/RNA-amplification techniques are the polymerase chain reaction (PCR), the ligase chain reaction (LCR), and the transcription-mediated amplification (TMA) tests. Regrettably, the test evaluation process undergone by these tests has not always been rigorous or scientifically sound.