Behind the scenes of EQA - characteristics, capabilities, benefits and assets of external quality assessment (EQA).

External quality assessment (EQA) cycles are the smallest complete units within EQA programs that laboratories can use to obtain external assessments of their performance. In each cycle, several samples are distributed to the laboratories registered for participation, and ideally, EQA programs not only cover the examination procedures but also the pre- and post-examination procedures. The properties and concentration range of measurands in individual samples are selected with regard to the intended challenge for the participants so that each sample fulfils its purpose.

Behind the scenes of EQA - characteristics, capabilities, benefits and assets of external quality assessment (EQA).

Providers of external quality assessment (EQA) programs evaluate data or information obtained and reported by participant laboratories using their routine procedures to examine properties or measurands in samples provided for this purpose. EQA samples must offer participants an equal chance to obtain accurate results, while being designed to provide results in clinically relevant ranges. It is the responsibility of the EQA provider to meet the necessary requirements for homogeneity, stability and some other properties of the EQA items in order to offer participants a fair, reliable and technically interesting EQA experience.

The European Organisation of External Quality Assurance Providers in Laboratory Medicine (EQALM) Statement: guidelines for publishing about interlaboratory comparison studies (PubILC).

Data and results from interlaboratory comparison (ILC) studies, external quality assessment (EQA) and proficiency testing (PT) activities are important and valuable contributions both to the further development of all disciplines of medical laboratory diagnostics, and to the evaluation and comparison of diagnostic assays. So far, however, there are no recommendations as to which essential items should be addressed in publications on interlaboratory comparisons. The European Organization of External Quality Assurance Providers in Laboratory Medicine (EQALM) recognized the need for such recommendations, and these were developed by a group of experts.

Optimization of a Nucleophilic Two-Step Radiosynthesis of 6--(2-[F]fluoroethyl)-6--desmethyl-diprenorphine ([F]FE-DPN) for PET Imaging of Brain Opioid Receptors.

We have established a method for nucleophilic one-pot, two-step radiosynthesis of the popular opioid receptor radioligand 6--(2-[F]fluoroethyl)-6--desmethyl-diprenorphine ([F]FE-DPN) from the novel precursor 6--(2-tosyloxyethyl)-6--desmethyl- 3--trityl-diprenorphine (TE-TDDPN), which we designate as the Henriksen precursor. We undertook an optimization of the synthesis conditions, aiming to enhance the accessibility of [F]FE-DPN for positron emission tomography (PET) studies of μ-opioid receptors. Herein, we report an optimized direct nucleophilic F-fluorination and the deprotection conditions for a fully automated radiosynthesis of [F]FE-DPN on a modified GE Tracerlab FX FE synthesis panel.