Analysis of patient results distributions to reevaluate a reference range change for calcium, after a change in assay reagents on the Roche Cobas c500 analyzer

Authors

Upasana Joneja, MD, Thomas Jefferson University Hospital, Philadelphia, PAFollow
Laura J. McCloskey, MD, Thomas Jefferson University Hospitals, Philadelphia, PAFollow
Douglas F. Stickle, MD, Thomas Jefferson University Hospitals, Philadelphia, PAFollow

Document Type

Poster

Publication Date

2015

Abstract

Introduction:

A change in reagents for calcium (Ca) on the Roche Cobas c500 used in our laboratory analyzer took place in 2013. The previous reference range (8.5-10.5 mg/dL) was replaced with that from the manufacturer's study (8.6-10.0 mg/dL), based on correlation of results between the new and old assays. As a matter of quality assurance, we undertook a post-assay-change reevaluation of the reference range change, using a method based on that of Bhattacharya [1]. In short, the method relies on the assumption that the reference range is a normal distribution, which assumption enables this distribution to be isolated mathematically from within all-comers patient distribution data that are not normally distributed.

Recommended Citation

Joneja, MD, Upasana; McCloskey, MD, Laura J.; and Stickle, MD, Douglas F., "Analysis of patient results distributions to reevaluate a reference range change for calcium, after a change in assay reagents on the Roche Cobas c500 analyzer" (2015). Department of Pathology, Anatomy, and Cell Biology Resident's Posters. Paper 17.
https://jdc.jefferson.edu/pacbresidentposters/17