title: Application of R-charts to detection of random errors: a computer simulation study.
abstract: The application of R-charts to quality control in clinical chemistry was investigated. These charts are widely used in statistical process control and plot the range (ie the difference between the highest and the lowest values) of a set of controls. A set of five control serums was considered. A computer simulation program was developed for this investigation. It showed a power function that is remarkably insensitive to systematic errors. Consequently these charts may be a useful tool in discriminating between systematic and random errors, helping the trouble-shooting significantly, if used concurrently with Levey-Jennings' charts. Nevertheless, as several control samples are necessary, this technique is not cost-effective for short analytical runs.
authors.affiliation: Department of Laboratory Medicine, Al Hada Armed Forces and Airbase Hospital Complex, Taif, HHRC 578 Saudi Arabia.
authors.forename: P F
authors.initials: PF
authors.lastname: Laget
mesh_terms: D015982:Bias; D003198:Computer Simulation / Q000706:statistics & numerical data*; D003404:Creatinine / Q000097:blood; D006801:Humans; D011786:Quality Control; D014508:Urea / Q000097:blood
chemical_list: D014508:Urea; D003404:Creatinine