ANALYTICAL AND POST-ANALYTICAL

ERROR IN CLINICAL CHEMISTRY

LABORATORYHanisha Erica P. Villaester, RMT

Analytical Errors

Analytical Errors• Test System Not Calibrated• Results reported when control results out of range• Improper measurements of specimens and/or reagents• Reagents prepared incorrectly• Reagents stored inappropriately or used after expiration

date• Instrument maintenance not dance• Dilution and pipetting errors

Analytical Errors

• Inaccuracy• Imprecision Errors• Insensitivity• Linearity Issues

Analytical Errors• Inaccuracy• Invalidates reference ranges and cut-off points• May lead to inappropriate therapy or failure to treat• May lead to misdiagnosis• May lead to failure to diagnose

• Imprecision Issues• Poor reproducibility invalidates patient monitoring using

laboratory results

Analytical Errors• Insensitivity

• A change in assay sensitivity leads to issue of detection• Affects robustness of results near the detection limit

• Linearity Issues• A clear understanding of the linearity of a method is essential to

ensure that grossly inaccurate results are not reported where there are high concentrations or activities of analytes

Post-Analytical Errors

Post-Analytical Error

• Transcription errors in reporting• Report sent to the wrong location• Report illegible• Report not sent

Summary• Pre-Analytical Errors• 46 – 68.2%• Insufficient sample• Sample condition• Sample handling• Incorrect Identification• Incorrect sample

• Analytical Error• 7 – 13.3 %• Equipment Malfunction• Sample Mix up• Interference

• Post-Analytical• 18.5 – 47 %• Reporting and Interpreting• Improper date entrye

Impact of Errors• Inadequate or improper patient care• Inconvenience to patient• Misdiagnosis• Harm to patient• Death

WHAT SHOULD WE DO?• Develop systematic workflow• Identify critical processes• Continuous monitoring• Predict accidental events so preparation may be ahead• Strengthen defences and decrease vulnerability

References• Odell, M. (Feb 2014). CSE Senior Design 1. Retrieved from

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