Education

1. ANALYTICAL AND
POST-ANALYTICAL ERROR IN
CLINICAL CHEMISTRY
LABORATORY
Hanisha Erica P. Villaester, RMT

2. Analytical Errors

3. 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

4. Analytical Errors
• Inaccuracy
• Imprecision Errors
• Insensitivity
• Linearity Issues

5. 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

6. 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

7. Post-Analytical Errors

8. Post-Analytical Error
• Transcription errors in reporting
• Report sent to the wrong location
• Report illegible
• Report not sent

9. 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

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

11. 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

12. References
• Odell, M. (Feb 2014). CSE Senior Design 1. Retrieved from
https://www.google.com.ph/url?sa=t&rct=j&q=&esrc=s&source=web&cd=35&cad
=rja&uact=8&ved=0CDUQFjAEOB5qFQoTCNL0jbC99MYCFYUmlAodnY8CvQ&url=ht
tp%3A%2F%2Franger.uta.edu%2F~odell%2FCSE_4316_Senior_Design_I%2FCSE%25
204316%2520Classic%2520Mistakes.ppt&ei=946yVZKdLIXN0ASdn4roCw&usg=AFQ
jCNFgWECvcwF_hLS-nwPKhoXuOs0cAA&bvm=bv.98476267,bs.1,d.c2E