RPEM: Randomized Monte Carlo parametric expectation maximization algorithm.

Inspired from quantum Monte Carlo, by sampling discrete and continuous variables at the same time using the Metropolis-Hastings algorithm, we present a novel, fast, and accurate high performance Monte Carlo Parametric Expectation Maximization (MCPEM) algorithm. We named it Randomized Parametric Expectation Maximization (RPEM). We compared RPEM with NONMEM's Importance Sampling Method (IMP), Monolix's Stochastic Approximation Expectation Maximization (SAEM), and Certara's Quasi-Random Parametric Expectation Maximization (QRPEM) for a realistic two-compartment voriconazole model with ordinary differential equations using simulated data. We show that RPEM is as fast and as accurate as the algorithms IMP, QRPEM, and SAEM for the voriconazole model in reconstructing the population parameters, for the normal and log-normal cases.

Economic impact of clinical pharmaceutical activities in hospital wards: A systematic review.

BACKGROUND: The positive impact of clinical pharmacy services (CPS) in improving clinical outcomes such as reduction of drug related problems is well demonstrated. Despite these results, the deployment of these activities is not systematically observed in the hospital setting. OBJECTIVES: This systematic review first aimed to describe existing evidence regarding economic evaluation of ward-based CPS focusing on the entire treatment of a patient in a hospital setting. Secondly, the quality of economic evaluations of existing evidence was assessed. METHODS: A comprehensive literature search was performed in PubMed/Medline, Science Direct and the NHS Economic Evaluation databases from January 2000 to March 2019. English or French language articles describing an economic evaluation of ward-based CPS on inpatients in hospital settings were included. Articles not describing a single study, dealing with a CPS not considering the entire medication regimen of the patient or presenting both inpatient and outpatient CPS were excluded. Selected articles were analyzed according to Drummond's check-list for assessing economic evaluations. RESULTS: Forty-one studies were included. About one third were American publications. CPS implemented in ICU represented about half of the selected articles. Pharmacist-to-bed ratios varied according to countries and care unit type with the most favorable ratios in ICU and in American studies. Cost-avoidance was mostly used to express economic impact and ranged from €1579 to €3,089 328. Studies yielding the greater economic impact were conducted in the USA with implementation of full-time equivalents pharmacists or establishing of collaborative practice agreements. Only 6 articles dealt correctly with at least 7 of the 10 Drummond's checklist assessment criteria. CONCLUSION: This review suggests that the existing evidence is not sufficient to conclude to a positive economic impact of CPS conducted according to clinical pharmacy guidelines. Funding resources, remuneration of clinical pharmacy activities and provision of standardized national clinical and economic databases appear to be essential evolutions to improve CPS development.