Safety in numbers 5: Evaluation of computer-based authentic assessment and high fidelity simulated OSCE environments as a framework for articulating a point of registration medication dosage calculation benchmark Mike Sabin a , Keith W. Weeks b, * , David A. Rowe c , B. Meriel Hutton d , Diana Coben e , Carol Hall f , Norman Woolley b a NHS Education for Scotland, UK b Faculty of Health, Sport & Science, University of Glamorgan, UK c University of Strathclyde, UK d King’s College London, UK e National Centre of Literacy and Numeracy for Adults, The University of Waikato, New Zealand f School of Nursing, University of Nottingham, UK article info Article history: Accepted 17 October 2012 Keywords: Validity Reliability Measurement Assessment Evaluation Numeracy Medication dosage calculation abstract This paper reports a key educational initiative undertaken by NHS Education for Scotland (NES), based upon recommendations from a ‘Numeracy in Healthcare’ consultation. We report here the design of a web-based technical measurement authentic assessment environment evolved from the safeMedicate suite of programs that provided a model for an environment within which a medication dosage calcu- lation problem-solving (MDC-PS) benchmark could be articulated. A sample of 63 third-year pre-regis- tration nursing students was recruited from four participating universities in the UK. A counterbalanced design was employed where the virtual authentic assessment environment was evaluated for internal consistency reliability and criterion-related validity against an objective structured clinical assessment (OSCE) undertaken in high-fidelity simulated clinical environments. Outcome measures indicated an extremely high internal consistency of the web-based environment. It was concluded that the combi- nation of a web-based authentic assessment environment and further assessment of safe technical measurement interpretation and dexterity in a practice/practice simulation setting, populated with a benchmark and a criterion referenced rubric validated by the profession, is an innovative, viable, valid and reliable assessment method for the safe administration of medicines. As a result, the rubric for assessment of the appropriate range of calculation type and complexity informed the NMC’s revised Essential Skills Clusters for Medicines Management (NMC, 2010a; NMC, 2010b). This inclusion provides a particularly strong example of both research directly influencing policy and of evidence-based regulation. Ó 2012 Published by Elsevier Ltd. Introduction This paper advances the concept of competency benchmarking in nursing numeracy and authentic assessment of technical measurement competence. This is explored within the context of a NHS Education for Scotland (NES) commissioned programme of research that evaluated the internal reliability and criterion-related validity of an authentic assessment environment within which a point of nurse registration dosage calculation benchmark could be articulated (Full report available at: Coben et al., 2010) www. nursingnumeracy.info). NES commissioned an interdisciplinary expert reference group of healthcare numeracy experts from across the UK to: 1. Explore and propose the relationship between numeracy, healthcare & nursing numeracy, medicines management & MDC-PS. 2. Advance the concept and rationale for competency bench- marking in nursing numeracy. 3. Develop an authentic assessment framework within which a point of registration medication dosage calculation bench- mark, reflecting a hierarchy of medication dosage and intra- * Corresponding author. E-mail address: kweeks@glam.ac.uk (K.W. Weeks). Contents lists available at SciVerse ScienceDirect Nurse Education in Practice journal homepage: www.elsevier.com/nepr 1471-5953/$ e see front matter Ó 2012 Published by Elsevier Ltd. http://dx.doi.org/10.1016/j.nepr.2012.10.009 Nurse Education in Practice 13 (2013) e55ee65