QA and basic statistics

Question 1

Define sensitivity and specificity

Answer 1

Sensitivity: measurement of the rate of positive tests in patients who HAVE the condition

SN=true positives/true positives+false negs

• a negative result in a highly sensitive test rules out the condition

Specificity: measurement of the rate of negatives in patients who do not have the condition

SP=true negatives/true negatives+false positives

• a positive result in a highly specific test means the condition is present

Question 2

Define positive and negative predictive value

Answer 2

• PPV: ability of a test to identify true positives among many positive tests
• NPV: ability of a test to identify true negatives among many negative tests

Question 3

Make a table illustrating sensitivity specificity PPV NPV

Answer 3

Question 4

Define proficiency testing

Answer 4

• Proficiency testing is a procedure for evaluating unknown specimens by pathologists or by a lab test, in which the results are retained and compared to a reference standard and to other participating laboratories

Question 5

What quality assurance procedures can be used in surgical pathology?

Answer 5

• Preanalytical: monitor speimen delivery timeliness, monitor adequacy of clinical history, monitor specimen identification errors & lost specimens, monitor errors in accession, fixation
• Analytical: Monitor errors in grossing, dictation, cutting, staining;
  prospective: perform intradepartmental consultations, convene consensus conferences
  retrospective: comparte frozen section/permanent section correlation, review cytology-histology correlation, perform random case reviews, perform targetted organ system reviews, convene intradepartmental and multidiscipline conferences, perform interinstitutional reviews
• post-analytical: monitor turnaround time, review report quality, use of synoptic reporting, review addendum reports, review record keeping, storage, review ammended reports

Question 6

How would you establish a quality assurance program in anatomical pathology?

Answer 6

• Establish a quality assurance committee including a medical leader, technical managers and quality assurance coordinators
• Develop a quality assurance plan based on the CAP standards; structure plan based on pre-analytical, analytical and post-analytical timepoints
• Convene regular comittee meetings to review, monitor and evaluate various aspects of the laboratory service as detailed aboe to ensure standards are being met
• Identify quality improvement opportunities and manage unexpected events

Question 7

What are universal precautions in laboratories?

Answer 7

• Universal precautions are a standard set of equipment and protective procedures designed to protect the individual from harm; apply to semen, human tissue, CSF, synovial fluid, pleural/peritoneal/pericardial/amniotic fluid
• Routine use of appropriate barrier precautions: gloves, aprons, masks, protective eyewear to prevent skin and mucous membrane exposure to blood/body fluids
• Workers should wash their hands immediately and thouroughly if contaminated with blood or other fluids
• Workers should change their gloves and wash their hands after completing specimen processing
• Workers should take precautions to prevent injuries caused by needles, scalpels, other sharp instruments during procedures
• Workers should place sharps in designated containers
• Workers should use biologic safety cabinets for procedures generating droplets
• Never use mouth for pipetting
• Should decontaminate after spills and equipment after use
• Should wash their hands/remove protective equipment before leaivng lab
• consult CDC, provincial and national guidelines

Question 8

A surgeon approaches you because he disagrees with a diagnosis your colleague made. Describe next steps.

Answer 8

• Get more information as to what the disagreement entails and reasons for not approaching colleage
• review case, pull slides/blocks, contact colleage and review
• if there is a change in diagnosis, work with colleage to issue addendum
• Clarify with the surgeon if he wants more cases reviewed, meet with lab director
• If you realize your colleague is making many errors, contact lab director
• if colleague refuses to get remedial training, document carefully and remain in contact with lab director and provincial college