Vitamin D retesting by general practitioners: a factor and cost analysis.

OBJECTIVES: Vitamin D testing by Primary Care doctors is increasing, placing greater workloads on healthcare systems. There is little data though on vitamin D retesting in Ireland. This study aims to investigate the factors associated with vitamin D retesting by Irish General Practitioners (GPs) and examine the resulting costs. METHODS: This is a retrospective analysis over 5 years (2014-2018) of GP requested 25-hydroxyvitamin D (25(OH)D) results in 36,458 patients at a major city hospital in Dublin, Ireland. Those with one test were compared with individuals who were retested and samples categorised to determine changes in status between tests. RESULTS: Nearly one in four patients (n=8,305) were retested. Positive predictors of retesting were female (p<0.001), age (60-69 years, p<0.001), location (Co. Kildare, p<0.001) and initial deficiency (<30 nmol/L, p<0.001) or insufficiency (30-49.9 nmol/L, p<0.001). Vitamin D status improved on retesting, with deficiency halving on first retest (9 vs. 18%, p<0.001) and dropping to 6% on further retests. About 12.2% of retests were done within 3 months and 29% had ≥2 retests within 1 year. 57% of retests were in those initially vitamin D replete (>50 nmol/L). The annual cost of inappropriate testing was €61,976. CONCLUSIONS: One in four patients were retested and this varied by age, gender and patient location. Over 10% of retests were inappropriately early (<3 months), a third too frequent and over half were in replete individuals incurring significant costs. Clear guidance for GPs on minimum retesting intervals is needed, as well as laboratory ordering systems to limit requests using pre-defined criteria.

Trends in HIV testing and associated factors among men in South Africa: evidence from 2005, 2008 and 2012 national population-based household surveys.

OBJECTIVES: In Sub-Saharan African countries, including South Africa, uptake of human immunodeficiency virus (HIV) testing among men remains a major challenge. Few studies have explored HIV testing uptake among men and factors that influence their testing behaviours. This article explores trends in HIV testing uptake and associated factors among men aged 15 years and older in South Africa using national HIV population-based household surveys conducted in 2005, 2008 and 2012. STUDY DESIGN: A multistage cross-sectional design was used in the three nationally representative household-based surveys. METHODS: P-trend Chi-squared statistic was used to analyze changes in HIV testing in relation to demographic factors, and HIV-related risk behaviours across the three surveys. Univariate and multivariate logistic regression models were used to assess the associations between ever testing for HIV, demographic factors and HIV-related risk behaviours. RESULTS: HIV testing uptake among men was 28% in 2005, 43% in 2008 and 59% in 2012. A trend was also observed in HIV testing by sociodemographic factors, but differences existed within variables. HIV testing uptake was mainly influenced by the effects of selected population characteristics. Reduced likelihood of HIV testing was significantly associated with males aged 15-24 years, Black African race group, being single and unemployed, those residing in urban informal and rural informal areas, and those men who ever had sex. CONCLUSION: The observed sociodemographic differentials suggest that an effective expansion strategy for HIV testing needs to prioritize those most unlikely to test as identified by the current findings.

Exploration of E. coli contamination drivers in private drinking water wells: An application of machine learning to a large, multivariable, geo-spatio-temporal dataset.

Groundwater resources are under increasing threats from contamination and overuse, posing direct threats to human and environmental health. The purpose of this study is to better understand drivers of, and relationships between, well and aquifer characteristics, sampling frequencies, and microbiological contamination indicators (specifically E. coli) as a precursor for improving knowledge and tools to assess aquifer vulnerability and well contamination within Ontario, Canada. A dataset with 795, 023 microbiological testing observations over an eight-year period (2010 to 2017) from 253,136 unique wells across Ontario was employed. Variables in this dataset include date and location of test, test results (E. coli concentration), well characteristics (well depth, location), and hydrogeological characteristics (bottom of well stratigraphy, specific capacity). Association rule analysis, univariate and bivariate analyses, regression analyses, and variable discretization techniques were utilized to identify relationships between E. coli concentration and the other variables in the dataset. These relationships can be used to identify drivers of contamination, their relative importance, and therefore potential public health risks associated with the use of private wells in Ontario. Key findings are that: i) bedrock wells completed in sedimentary or igneous rock are more susceptible to contamination events; ii) while shallow wells pose a greater risk to consumers, deep wells are also subject to contamination events and pose a potentially unanticipated risk to health of well users; and, iii) well testing practices are influenced by results of previous tests. Further, while there is a general correlation between months with the greatest testing frequencies and concentrations of E. coli occurring in samples, an offset in this timing is observed in recent years. Testing remains highest in July while peaks in adverse results occur up to three months later. The realization of these trends prompts a need to further explore the bases for such occurrences.

State Trends in HIV Testing Among US Adults Aged 18-64 Years, 2011-2017.

OBJECTIVES: HIV testing identifies persons living with HIV and can lead to treatment, decreased risk behaviors, and reduced transmission. The objective of our study was to describe state-level trends in HIV testing in the general US adult population aged 18-64 years, for both ever tested for HIV and tested for HIV in the previous 12 months. METHODS: Using 2011-2017 Behavioral Risk Factor Surveillance System data, we estimated the percentage of the state population, plus the District of Columbia, aged 18-64 years ever tested for HIV and tested for HIV in the previous 12 months. The 50 states and the District of Columbia were grouped according to the estimated prevalence of HIV in 2011. We used orthogonal contrasts to calculate P values for linear trends. RESULTS: The percentage of the population ever tested for HIV increased significantly in 23 states during 2011-2017, whereas the percentage tested for HIV in the previous 12 months increased significantly in 8 states. In 2017, the mean percentage ever tested for HIV in states with a high prevalence of HIV was 8.6 percentage points higher than the mean percentage in states with a low prevalence of HIV (48.5% vs 39.9%); the mean increase in the percentage ever tested was highest (11.4%) in states with a low prevalence of HIV. CONCLUSION: Enhanced efforts by states to make HIV testing simple, accessible, and routine are needed to reduce the number of persons who are not aware of their infection.