Pakistan Society Of Chemical Pathologists Zoom Series of Lectures ZT 24. Quality Managent 1 Brig Aamir Ijaz MCPS, FCPS, FRCP (Edin), MCPS-HPE HOD and Professor Chemical Pathology AFIP Rawalpindi

Specific Learning Outcome At the end of this lecture the students will be able to describe the processes involved in Quality Management.

Task 1 Write FIVE Qs of total quality management

TQM Framework

MCQ No 1 A. Quality Assessment A laboratory manager is concentrating on the measures like reducing turnaround time, specimen identification, patient identification and test utility. Which of the following term best describes these processes: Quality Assessment Quality Control Quality Improvement Quality Laboratory Processes Quality Planning   A. Quality Assessment

Quality Assurance / Assessment (QA) An all inclusive / comprehensive system monitoring the accuracy of test results where all steps before, during and after the testing process are considered. It includes pre-analytic, analytic and post analytic factors Provides a structure for achieving lab and hospital quality goals

Quality Control (QC) QC systems monitor the analytical process; detect and minimize errors during the analysis and prevent reporting of erroneous test results. It is like ‘product testing’ in an industry It uses statistical analysis of test system data Requires Westgard Rules

Types of QC Internal Daily Establishment of reference ranges Validation of a new reagent lot and/or shipment Following instrument repair

Types of QC External Proficiency Testing Determination of laboratory testing performance by means of intra-laboratory comparisons NEQAPP in Pakistan CAP, CLIA, The Joint Commission requirement Must be integrated within routine workload and analyzed by personnel who are running the tests. Ongoing evaluation of results to correct for unacceptable results Used to access employee competency

QC Material

Task 2 Please write the following control materials in the order of the accuracy and reliability: Lyophilized, bovine, un-assayed controls Lyophilized, bovine, assayed controls Liquid, human, and assayed controls  

QC Materials Human or Bovine Lyophilized or Liquid Assayed or Unasssayed

Human or Bovine Why human is better than bovine? Values are closer to patient values (obviously) What precaution required in human? Infection free

Lyophilized or Liquid Which is better? Liquid Why? No pipetting error What is the disavantage Higher cost

Assayed or Unasssayed Why human is better than bovine? Values are closer to patient values (obviously) What precaution required in human? Infection free

Some Basic Statistics

D. Symmetrical distribution MCQ No 2 Normal data means: Labs own generated values Result of disease free subjects Result of healthy individuals Symmetrical distribution Values within reference range D. Symmetrical distribution

Gaussian/Normal Distribution All values are symmetrically distributed around the mean Characteristic “bell- shaped” curve Assumed for all quality control statistics

MCQ No 3 D. Standard Deviation Which of the following is NOT a measure of central tendency? Average Mean Median Mode Standard deviation D. Standard Deviation

Measures Of Central Tendency Mean (x̄) - the mathematical average of a group of numbers, determined by adding a group of numbers (events) and dividing the result by the number of events Median - determined as the ‘middle’ of a group of numbers that have been arranged in sequential order. That is to say, there are an equal number of numbers on either side of the ‘middle’ number. In an odd # of observations, it is the middle observation. In an even # of observations, average the two middle values. Mode - the number that appears most frequently in a group of numbers. There can be more than mode, or none at all.

Standard Deviation (SD) Is a mathematical expression of the dispersion of a group of data around a mean.

Standard Deviation : n = the number of observations (how many numerical values ) Σ = the sum of … in this case, the sum of = the mean value X = the value of each individual observation The Standard Deviation is an expression of dispersion … the greater the SD, the more spread out the observations are

Standard Deviation and Probability For a set of data with a normal distribution, a value will fall within a range of: +/- 1 SD 68.2 % of the time +/- 2 SD 95.5% of the time +/- 3 SD 99.7% of the time

Which is a Better Assay? FSH Concentration SD 1 0.09 5 0.25 10 0.40 25 1.20 100 3.80

Coefficient of Variation (CV) % Analyte: FSH Concentration SD CV 1 0.09 9.0 5 0.25 5.0 10 0.40 4.0 25 1.20 4.8 100 3.80 3.8 The smaller the CV, the more reproducible the results: more values are closer to the mean. Useful in comparing 2 or more analytical methods Ideally should be less than 5 %

Coefficient of Variation (CV) Indicates what percentage of the mean is represented by the standard deviation Reliable means for comparing the precision or SD at different units or concentration levels Expressed as a percentage CV% = Standard deviation X 100 mean

Establishment of a QC System Two or three levels of control material used A control is a material or preparation used to monitor the stability of the test system within predetermined limits Measure of precision and reproducibility Purpose: verify the analytic measurement range of instrument for a specific analyte

Establishment of a QC System Collecting data Run assay on control sample & manually enter control results on chart One chart for each analyte and for each level of control

Collecting Data For QC Charting techniques Levey Jennings chart is a graph that plots QC values in terms of how many standard deviations each value is from the mean

Use of Standard Deviation Once you have determined the standard deviation, must use the information to evaluate current/ future analysis. Most labs make use of ± 2 SD or 95% confidence limit. To put this into a workable form, you must establish the range of the ± 2 SDs

So, How Do We Determine The Range Of Acceptable Results ? Scenario Mean of group of control values = 104 mg/dL Standard Deviation = ± 5 mg/dL Determine the Range of ± 2SD; (which will allow you to evaluate acceptability of performance of the control on subsequent days.) Is a control value of 100 mg/dL acceptable?

Thank You