Upsala J Med Sci 95: 259, 1990 

The Regional Tkansferability Project 
Elin Olafsdottir,' Torsten Aronsson,' Torgny Groth' and Carl-Henric de Verdie? 

'Department of Clinical Biochemistry, Landspitalinn, Reykjavik, 'Department of 
Clinical Chemistry and 'Unit f o r  Biomedical Systems Analysis, 

University of Uppsala, Uppsala, Sweden 

Analytical data from S-Creatinine and S-Urate from the Uppsala- 
Orebro regional quality assurance program have been studied for 
a period of more than a year with weekly samples of different 
concentrations. The analytical bias and analytical stability of 
the about 20 participating laboratories is estimated over time. 
The systematic error estimated by linear least squares fit of the 
measured values vs assigned values shows for some of the 
laboratories an unacceptably large bias outside the reference 
ranges for a healthy population. Analytical stability estimated 
over different time periods from slope and intercept of 
regression lines are of different degree of acceptability. Steps 
to reduce the interlaboratory variability will be suggested and 
the investigation will be extended in order to study the 
possibility to use transformation functions for transfer of data 
by collection of data from e g reference populations with defined 
condition of health from different geographical areas. 

A report of this study has been prepared and will be published 
elsewhere. 

Correspondence: 
Professor Carl-Henric de Verdier 
Department of Clinical Chemistry, University of Uppsala 
Postal address: University Hospital 
S-751 85 Uppsala, Sweden 

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