Difference between revisions of "Quality"
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=Quality standards organization= | =Quality standards organization= | ||
There are a large number of organizations that have written standards for quality in laboratory medicine. | There are a large number of organizations that have written standards for quality in laboratory medicine. | ||
==International== | ==International== | ||
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==Canada== | ==Canada== | ||
===Canadian immunohistochemistry quality control=== | |||
*Abbreviated ''CIQC''. | |||
*[https://ciqc.ca/Pages/default.aspx CIQC webpage (ciqc.ca)] | |||
===Ontario=== | ===Ontario=== | ||
*[[Institute for Quality Management in Healthcare]] - previously ''Quality Management Program - Laboratory Services''. | *[[Institute for Quality Management in Healthcare]] - previously ''Quality Management Program - Laboratory Services''. | ||
Revision as of 17:25, 14 February 2017
Quality, in pathology, has got a lot of attention lately because there have been high-profile irregularities that lead to significant harm.[1][2]
General
The keys to quality are:
- Understanding the needs of the stakeholders (surgeons, oncologists, patients, other pathologists, the public at large).
- Understanding the processes.
- Developing measures of quality.
- Tracking the measures of quality & assessing their validity.
- Understanding the causes of failures/adverse events in the context of the processes.
- Continually doing all of the above with the aim of improving outcomes - continuous quality improvement.
Definitions
System documentation and description
Quality Management Program-Laboratory Services (QMP-LS) defines a hierarchy of documentation:[3]
- Policy.
- Process
- Procedures.
Policy
- High level document
- Describes rationale for processes, defines goals/objectives - includes parameters that can be measured.
Process
- Intermediate level document.
- Defines input and outputs, outlines the steps taken to achieve an objective - should not be overly detailed.
Procedure
- Low level document.
- Detailed line-by-line instructions - description of the workflow.
Other
Quality control
- Examines whether a process is hitting its target(s) for its measure(s) of quality.
In short: Does it hit the targets?
Quality assurance
- Program to insure that a process is yielding the desired output(s).
In short: Does it produce the desired output?
Analysis
Overview
Quality issues can be examined in a number of different ways.
Finding a problem:
- Root cause analysis.
Anticipating problems:
- Failure mode and effects analysis (FMEA).
General error analysis
Pathology errors happen any time from when the lab gets the specimen until after the report is issued.
When errors happen:
- Work-up the problem.
- Where did the error occur? Pathologist error?
- Talk to the clinician.
- If it is a critical diagnosis contact the most-responsible physician immediately... if they are unreachable call the physician on-call for the most-responsible physician... if the patient is out-of-town you may have to coordinate with the local emergency department.
- Talk to the chief of pathology.
- Incident report.
- Reconstruct error.
- Was it a specimen mix-up?
- Is there another error?
- Was it a specimen mix-up?
- Amend the report(s).
- Remedy the source of error.
The classic structural break down
A classic structural break down for error analysis is:
| Errors in pathology | |||||||||||||||||||||||||||||||||
| Pre-analytical errors | Analytical errors | Post-analytical errors | |||||||||||||||||||||||||||||||
Note:
- This break down is arbitrary and in of itself most useful for answering exam questions.
- In a practical context, it is a frame work for classifying errors. It is not useful for understanding the source of an error or addressing it.
Pre-analytic errors
- Container mix-up - pre-lab & in-lab.
- Block mix-up.
- Slide mix-up - labels wrong.
- Poor quality slides (fixation, processing, staining).
- Lost specimen - can be potentially anywhere in the process.
Analytic errors
- Interpretation wrong.
- Factors:
- Difficult case.
- Technical factors (quality of slides).
- Lack of clinical history.
- Factors:
Post-analytic errors
- Wrong case signed-out.
- Filing problem/lost report.
- Interpretation of report problem (poorly written report, misinterpretation).
Sources of error
- "Human error".
- Training.
- Work flow.
- Process gaps.
- Process control.
- Lack of redundancy.
Types of errors
Can be subdivided into the following groups:[4]
- False-negative - missed diagnosis.
- False-positive - diagnosis made that on review considered not to be present.
- Threshold - difference of opinion regarding a diagnostic threshold.
- Type and grade.
- Missed margin.
- Other.
Grading of errors
May be subdivided by three groups:
- Grade 1: no consequence.
- Grade 2: possible consequence.
- Grade 3: definitely a consequence.
Error reduction
Various strategies can be employed:[5]
- Training of staff - on error handling.
- Computer order entry.
- Avoid duplication fatigue.
- Quick correlation with several identifying features.
- Full name, sex, date of birth -- these all appear when one opens a case.
- Barcode use.
- Avoid transcription errors.
- Clinical information entry required.
- Allow correlation with test.
- The interpretation may differ if the history says "screening coloscopy" versus "large cecal mass, anemia and weight loss" versus "breast cancer".
- Allow correlation with test.
- The use of algorithms to guide decisions where applicable.[6]
- Remove subjectivity.
- Increase objectivity, reproducibility.
Dealing with diagnostic errors
- Opinion is split on whether reports should be amended or addended - see sign out article.
Measures of quality
Any number of parameters can be used to measure quality. The when, where and how-often something is measured depends on the value-added.
General measures of quality
There are really only two:
- Timeliness, i.e. turn-around time (TAT).
- Error rate.
Note:
- 1 and 2 can be examined/quantified in any number of ways.
- Error, in the context of a measurement, has to be defined.
Internal measures of quality
Smaller categories
Smaller categories - errors:[7]
- Analytic: specimen identification & transport.
- Preanalytic/analytic: tissue processing, e.g. fixation, blocking, embedding, sectioning, staining.
- Analytic: interpretation.
- Postanalytic: reporting/report integrity.
Individual measures
Specific measures:[7]
- Preanalytic:
- Identification - numbers match requisition.
- Appropriate container.
- Analytic:
- Mislabeling.
- Interpretation errors - based on:
- Internal review.
- Cytology-histology correlation.
- Biopsy-resection correlation.
- Frozen section-permanent section correlation.
- Internal comparisons, e.g. ASCUS/LSIL between pathologists.
- External review.
- External standards/expected rate.
- Internal review.
- Amended reports - captures several of the above.
- Postanalytic:
- Completeness of report.
- Critical diagnosis timely?
- Report delivered to appropriate person?
External measures of quality
Benchmark
- An external quality measure, i.e. a comparison to an outside group or agency.
- Slides are sent around from an external source:
- Lab has to stain 'em and send 'em back for an assessment.
- Pathologists render diagnoses on 'em and are given the (externally rendered) consensus diagnosis.
- Slides are sent around from an external source:
Immunohistochemistry
Main article: Immunohistochemistry
Classification of IHC tests
IHC tests are classified in a paper by Torlakovic et al.:[8]
- Class I:
- Results used by pathologists.
- Adjunct to histomorphology.
- Examples: CD45, S-100.
- Class II:
- Used by clinicans for treatment decisions.
- Considered independent of the other information in the pathology report; thus, cannot be derived from other information in the report.
- Examples: ER, PR, HER2, Ki-67, CD117, CD20.
The implication of irregularies in the different classes are different. Problems in Class II tests are potentially more severe, as there is no internal control.
Work-up of suspected IHC problems
- Review controls (internal and external).
- Isolated to case vs. larger problem?
- Discuss with lab/make other pathologists aware of the issue.
- Isolated to case vs. larger problem?
- Repeat test - to identify the cause.
IHC process:
- Ischemia time - warm ischemia, preparation of specimen.
- Fixation - under, over, defective fixative, not enough fixative.
- Processing prior to antibody binding, usu. heating (antigen retrieval).
- Antibody-antigen binding.
- Reporter molecule binding.
- Counterstaining.
- Interpretation problem.
Notes:
- Problems can arise at any step.
Other
Data retention standards
- There are data retention standards - how long results have to be retained.
College of American Pathologists
- In the United States, there are standards from College of American Pathologists (CAP) and Clinical Laboratory Improvement Amendments (CLIA).[10]
Selected CAP and CLIA standards:[11]
- Cytology slide (non-fine needle aspiration): 5 years from the exam date.
- Fine needle aspiration: 10 years from the exam date.
- Histopathology slides: 10 years from the exam date.
Canadian Association of Pathologists
The Canadian standards are higher than the US ones.
Summary of selected suggestions:[12]
| Material | Origin | Suggested retention period | Additional notes |
|---|---|---|---|
| Wet tissue | surgical | 4 weeks after final report | - |
| Paraffin blocks | surgical | 20 years | 50 years for paediatric cases |
| Slides | surgical | 20 years | - |
| Wet tissue | autopsy | 3 months after final report | Coroners'/medical examiner cases may be longer |
| Paraffin blocks | autopsy | 10 years | Coroners'/medical examiner cases may be longer |
| Slides | autopsy | 10 years | Coroners'/medical examiner cases may be longer |
Failure-potential analysis
Adapted from Ullman:[13]
- Identify potential individual failures.
- Identify the consequences of those failures.
- Identify how the individual failures can arise.
- Identify the corrective action.
Biopsy size
Very small tissue fragments are associated with a decreased diagnostic yield and an increased diagnostic uncertainty.
Quality standards organization
There are a large number of organizations that have written standards for quality in laboratory medicine.
International
International standards organization
- Abbreviated ISO.
Standard:
- ISO 15189:2007.[14].
- Published in 2007. Supersedes a standard published in 2003.
Note:
- Unfortunately one has to shell out money to get a peak at 'em.
United States of America
Clinical laboratory improvement amendments
- Abbreviated CLIA.
- Published a multitude of standards & guidelines.[15]
College of American Pathologists
- Do laboratory accreditation.[16]
Canada
Canadian immunohistochemistry quality control
- Abbreviated CIQC.
- CIQC webpage (ciqc.ca)
Ontario
- Institute for Quality Management in Healthcare - previously Quality Management Program - Laboratory Services.
- Set-up by the Ontario Medical Assocation.
Two divisions:
- External quality assessment (EQA) - external laboratory proficiency testing.
- Ontario Laboratory Accreditation (OLA).
United Kingdom
- National Pathology Benchmarking Service (NPBS).[17]
See also
- Critical values.
- CAP checklists.
- Tissue floater.
- Histology artifacts.
- Waffle diagnosis.
- Workload measurement.
- Anatomical pathology laboratory processes.
References
- ↑ URL: http://www.attorneygeneral.jus.gov.on.ca/inquiries/goudge/index.html. Accessed on: 1 March 2011.
- ↑ Judicial inquiry probes faulty breast cancer tests. CBC website. URL: http://www.cbc.ca/news/background/cancer/inquiry.html. Accessed on: 30 January 2012.
- ↑ URL: http://www.qmpls.org/LaboratoryAccreditation/OLAActivitiesEducationalTools/OLAPresentations/tabid/111/id/11/Default.aspx). Accessed on: 18 April 2012.
- ↑ Renshaw, AA. (Mar 2001). "Measuring and reporting errors in surgical pathology. Lessons from gynecologic cytology.". Am J Clin Pathol 115 (3): 338-41. doi:10.1309/M2XP-3YJA-V6E2-QD9P. PMID 11242788.
- ↑ Fabbretti, G. (Jun 2010). "Risk management: correct patient and specimen identification in a surgical pathology laboratory. The experience of Infermi Hospital, Rimini, Italy.". Pathologica 102 (3): 96-101. PMID 21171512.
- ↑ Kahneman D. ["Als wären wir gespalten": Der Psychologe und Nobelpreisträger Daniel Kahneman über die angeborenen Schwächen des Denkens, trügerische Erinnerungen und die irreführende Macht der Intuition]. Der Spiegel. Nr. 21. 2012. URL: http://www.spiegel.de/spiegel/print/index-2012-21.html.
- ↑ 7.0 7.1 Nakhleh, RE. (Nov 2009). "Core components of a comprehensive quality assurance program in anatomic pathology.". Adv Anat Pathol 16 (6): 418-23. doi:10.1097/PAP.0b013e3181bb6bf7. PMID 19851132.
- ↑ Torlakovic, EE.; Riddell, R.; Banerjee, D.; El-Zimaity, H.; Pilavdzic, D.; Dawe, P.; Magliocco, A.; Barnes, P. et al. (Mar 2010). "Canadian Association of Pathologists-Association canadienne des pathologistes National Standards Committee/Immunohistochemistry: best practice recommendations for standardization of immunohistochemistry tests.". Am J Clin Pathol 133 (3): 354-65. doi:10.1309/AJCPDYZ1XMF4HJWK. PMID 20154273.
- ↑ Balachandran, N.; Oba, DE.; Hutt-Fletcher, LM. (Apr 1987). "Antigenic cross-reactions among herpes simplex virus types 1 and 2, Epstein-Barr virus, and cytomegalovirus.". J Virol 61 (4): 1125-35. PMC 254073. PMID 3029407. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC254073/.
- ↑ URL: http://www.cms.gov/clia/. Accessed on: 1 April 2012.
- ↑ URL: http://home.ccr.cancer.gov/lop/intranet/policymanual/generalpolicy/CAPCLIA.asp. Accessed on: 1 April 2012.
- ↑ URL: http://cap-acp.org/guide_retention-human-biologic-material.cfm. Accessed on: 6 May 2012.
- ↑ Ullman, David G. (1997). The mechanical design process. Toronto: McGraw-Hill Companies Inc.. ISBN 0-07-065756-4.
- ↑ URL: http://www.iso.org/iso/iso_catalogue/catalogue_ics/catalogue_detail_ics.htm?csnumber=42641. Accessed on: 18 April 2012
- ↑ URL: http://www.cms.hhs.gov/Regulations-and-Guidance/Legislation/CLIA/index.html?redirect=/clia/. Accessed on: 18 April 2012.
- ↑ URL: http://www.cap.org/apps/cap.portal?_nfpb=true&cntvwrPtlt_actionOverride=%2Fportlets%2FcontentViewer%2Fshow&_windowLabel=cntvwrPtlt&cntvwrPtlt{actionForm.contentReference}=laboratory_accreditation%2Faboutlap.html&_state=maximized&_pageLabel=cntvwr. Accessed on: 18 April 2012.
- ↑ URL: http://www.keele.ac.uk/pharmacy/general/npbs/. Accessed on: 18 April 2012.
External links
- UK national benchmarking (keele.ac.uk).
- Multirule quality control - (westgard.com) - statistical process control explained for the mathematically challenged.