Evaluation of the implementation of evidence-based pediatric asthma exacerbation treatments in a regional consortium of emergency medical Services Agencies.

OBJECTIVE: Asthma exacerbations are a frequent reason for pediatric emergency medical services (EMS) encounters. The objective of this study was to examine the implementation of evidence-based treatments for pediatric asthma in a regional consortium of EMS agencies. METHODS: This retrospective study applied the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) implementation framework to data from an EMS agency consortium in the Cincinnati, Ohio region. The study analyzed one year before an oral systemic corticosteroid (OCS) option was added to the agencies' protocol, and five years after the protocol change. We constructed logistic regression models for the primary outcome of Reach, defined as the proportion of pediatric asthma patients who received a systemic corticosteroid. We modeled Maintenance (Reach measured monthly over time) using time series models. RESULTS: A total of 713 patients were included, 133 pre- and 580 post-protocol change. In terms of Reach, 3% (n = 4) of eligible patients received a systemic corticosteroid pre-OCS versus 20% (n = 116) post-OCS. Multivariable modeling of Reach revealed the study period, EMS transport time, months since implementation of OCS, and number of bronchodilators administered by EMS as significant covariates for the administration of a systemic corticosteroid. For Maintenance, it took approximately two years to reach maximal administration of systemic corticosteroids. CONCLUSIONS: Indicators of asthma severity and time since the protocol change were significantly associated with EMS administration of systemic corticosteroids to pediatric asthma patients. The two-year time for maximal Reach suggests further work is required to understand how to best implement evidence-based pediatric asthma treatments in EMS.

Covariate-constrained randomization with cluster selection and substitution.

BACKGROUND: An ongoing cluster-randomized trial for the prevention of arboviral diseases utilizes covariate-constrained randomization to balance two treatment arms across four specified covariates and geographic sector. Each cluster is within a census tract of the city of Mérida, Mexico, and there were 133 eligible tracts from which to select 50. As some selected clusters may have been subsequently found unsuitable in the field, we desired a strategy to substitute new clusters while maintaining covariate balance. METHODS: We developed an algorithm that successfully identified a subset of clusters that maximized the average minimum pairwise distance between clusters in order to reduce contamination and balanced the specified covariates both before and after substitutions were made. SIMULATIONS: Simulations were performed to explore some limitations of this algorithm. The number of selected clusters and eligible clusters were varied along with the method of selecting the final allocation pattern. CONCLUSION: The algorithm is presented here as a series of optional steps that can be added to the standard covariate-constrained randomization process in order to achieve spatial dispersion, cluster subsampling, and cluster substitution. Simulation results indicate that these extensions can be used without loss of statistical validity, given a sufficient number of clusters included in the trial.

The prevalence of pre-treatment and acquired HIV drug resistance in Vietnam: a nationally representative survey, 2017-2018.

INTRODUCTION: Monitoring the population-level emergence and transmission of HIV drug resistance (HIVDR) is necessary for supporting public health programmes. This study provides a nationally representative prevalence estimate of HIVDR in people initiating antiretroviral therapy (ART) and estimates of acquired HIVDR and viral load (VL) suppression in people who have received it for 12 or ≥48 months in Vietnam. METHODS: The study was conducted between September 2017 and March 2018 following World Health Organization guidance. Thirty ART clinics were randomly sampled using probability proportional to size sampling from a total of 367 ART clinics in the country. RESULTS AND DISCUSSION: In total, 409 patients initiating ART were enrolled into the survey of pre-treatment HIVDR. The prevalence of any pre-treatment HIVDR was 5.8% (95% CI 3.4-9.5%), and the prevalence of non-nucleoside reverse transcriptase inhibitor resistance was 3.4% (95% CI 1.8-6.2%). Four hundred twenty-nine patients on ART for 12±3 months and 723 patients on ART for ≥48 months were enrolled into the surveys of acquired HIVDR. The prevalence of VL suppression (defined as <1000 copies/ml) in patients on ART for 12±3 and ≥48 months was 95.5% (95% CI 91.3-97.8%) and 96.1% (95% CI 93.2-97.8%), respectively. Among individuals with viral non-suppression, any HIVDR was detected in 11/14 (weighted prevalence 74.3%) of those on ART for 12±3 months and in 24/27 (weighted prevalence 88.5%) of those receiving ART for ≥48 months. CONCLUSIONS: This nationally representative study of HIVDR found high levels of VL suppression among those on ART for 12 and ≥48 months. Overall, high levels of VL suppression at both time points suggested good adherence among patients receiving ART and quality of treatment services in Vietnam. CLINICAL TRIAL NUMBER: Not applicable.