Laboratory Quality Control. Ppt

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m When a laboratory management is committed to meet a

patients need, this is done through an ongoing program of total quality management program m Total quality management may be referred to as: m Total quality control m Total quality leadership and m Continuous quality improvement or m Quality management system

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    m Quality laboratory process (QLPS) m Quality Assurance (QAS) m Quality assessment (QC) m Quality control (QC)

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   m QLPS includes analytical process as well as general

policies, practices and procedures that define how all aspects of work get done.

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  m Quality assurance means quality enhancement m Quality assurance aims at ensuring that the data

provided are reliable and relevant m Quality assurance involves all measures that can be taken to improve laboratory efficiency and effectiveness m It ensures laboratory performance with minimum risk for laboratory workers and gives maximum benefit to the individual and community

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     m Clinical usefulness of selected tests m Patient preparation m Sampling m Specimen handling m Preservation and storage m Transport m Identification and data processing which includes

reporting of results

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     u „edication to quality service must be central u A true commitment is required by lab directors,

managers and supervisors, if the efforts of the lab personnel are to be successful

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 Quality services are developed and maintained on the basis of the following: u Adequate space u Modern materials and equipments u Adequate stock of requirements and supplies u Adequate staffing u Budgetary resources u Proper supervision

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 m jducational background and experience of personnel

are important m High quality personnel can render high quality services. m In service, training is also needed, which can help develop and maintain skills

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  ood technical procedures are necessary in the following criteria: u Preanalytical variables u Analytical variables u Post analytical variables

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m Also known as proficiency testing m Quality Assessment is a means to determine the

quality of the results generated by the laboratory m Quality Assessment is a challenge to the QA and QC programs

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  m The aim of quality control is to ensure that the

results generated by the test are correct m QC emphasizes statistical control procedures and also includes reagent and standard checks, linearity checks, etc..

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 m The serum samples are collected m Pooled serum samples together ( 1-2 litres ) m Screen the serum sample for various infective diseases m Adjust the PH to 7.5 using concentrated sulphuric acid m „istribute 10 ml portions of this into several plastic

vials and store in the deep freezer and this is stable for 3 months

m jach day 1 vial is taken and bring it in to room

temperature, once it liquefies analyze the value m jnter the value on the quality control chart m If the value on a specific day falls within ± 2 S„ that

indicates all the reagent and standard are good m In case the value is above or below ± 2 S„ indicates

reagent or standard is deteriorated m Repeat the assay with fresh reagent and standard

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m The internal quality control can be maintained by going through a complete checklist of items to make sure that all laboratory systems are being monitored and in control. m This checklist includes: m m

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Maintenance of equipments and glassware. Quality control of reagents, standards, control materials and reference ranges. Method selection and evaluation.

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SD £ Standard deviation - extent of random variation £ SD = Àd2 n-1

d= difference of individual result from mean n= number of observations

2 2o-efficient of variation relative magnitude of variability while comparing two procedures

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2 % = (SD x 100)/mean

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ood Accuracy ood Precision

ood Precision Only

Neither ood precision Nor Accuracy

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  m jxternal quality control is a way to compare the

performance of a laboratory with reference to other laboratories. m Also known as proficiency surveys. Such proficiency testing programmes periodically provide samples of unknown results to participating laboratories. £ When a laboratory receives such a sample, it must analyze and return the results within a specified period of time for comparison with the results obtained from other laboratories participating in the proficiency survey.

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A value obtained by observation or measurement of a particular type of quantity on a reference individual

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      m All groups of reference individuals should be clearly defined m The patient examined should resemble sufficiently the

reference individuals in all respects other than those under investigation m The conditions under which the samples were obtained and

processed for analysis should be known

m All quantities compared should be of the same type m All laboratory results should be produced with the use of

adequately standardized methods under sufficient analytical quality control m The diagnostic sensitivity and specificity, prevalence and

clinical costs of misclassification should be known for all laboratory tests used

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  Reference individual * Reference population * Reference sample group * Reference value * Reference distribution * reference intervals`

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    Risk factor : m Dbesity m Hypertension m Risk from occupation of environment m enetically determined risk Intake of pharmacologically active agent : m „rug treatment for disease m Dral contraceptives m „rug abuse m Alcohol m Tobacco

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Specific physiological status : m Pregnancy m Stress m jxcessive exercise

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 m Age m Posture when sampled m Blood group (ABD) m Race m Circadian variation m Sex m „iet m Stage of menstrual cycle m jthnic background

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m Stage of pregnancy m jxercise m Time of the day when sampled m Fasting or non fasting m Use of tobacco m eographical location

º       m „iagnosis of disease m Screening for disease m „etermination of severity of the disease m Monitoring progress of disease m Monitoring response to therapy m Monitoring drug toxicity m Predicting response to treatment m Predicting prognosis m Reassurance to patients