Publications

Background: Calibration is the process of verifying and resetting the analyte performance with use of calibrators. Effective calibration of the analyte and its quality assurance by proficiency testing is a vital step for providing reliable patient results within relevant and acceptable turnaround time. Calibration frequency of an analyte is driven by quality control performance and stated manufacturer’s recommendation. This study was done to evaluate whether analyte calibration frequency recommended by manufacturer is adequate and sufficient to have a stable analyte performance.

Methods: This retrospective study was carried out in biochemistry laboratory, tertiary care hospital for a period of one year after procuring institutional ethical clearance. Data about number of calibrations including calibrator lot, quality control (QC) results for triiodothyronine (T3), tetraiodothyronine (T4), thyroid stimulating hormone (TSH), cortisol and troponin I from Abbott Architect ci8200 fully automated analyser were collected. Data was described using descriptive statistics.

Results: Calibration frequency of T3, T4, TSH, cortisol and troponin I did not adhere to manufacturer’s recommendations. Every new lot of reagents required additional calibration after initial acceptance. Reasons for calibration was mainly due to introduction of new lot and due to failure in QC performance.

Conclusion: Calibration of T3, T4, TSH, cortisol and troponin I is driven by analyte QC performance and claim of calibration stability by manufacturer cannot be considered as the final estimate for recalibrations.

Keywords: Abbott architect, calibration frequency, immunoassay, CMIA, TSH, T3, T4, cortisol, troponin-I.