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Quality control ppt BIOCHEMISTRY
 

Quality control ppt BIOCHEMISTRY

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  • Animated 3-D cube with changing pictures(Basic)Tip: This example uses six pictures grouped in four sets of three, so that during the animation, various pictures appear on the cube.To reproduce the effects on this slide, do the following:On the Home tab, in the Slides group, click Layout, and then click Blank.On the Insert tab, in the Illustrations group, clickPicture. In the Insert Picture dialog box, select a picture, and then click Insert.Select the picture. Under PictureTools, on the Format tab, in the Size group, click the Size and Position dialog box launcher. In the Format Picture dialog box, resize or crop the image so that the height is set to 3.42” and the widthis set to 3.42”. To crop the picture, click Crop in the left pane, and in the Crop pane, under Crop position, enter values into the Height, Width, Left, and Top boxes. To resize the picture, click Size in the left pane, and in the right pane, under Size and rotate, enter values into the Height and Width boxes.Under PictureTools , on the Format tab, in the Picture Styles group, in the bottom right corner click the Format Shape dialog box launcher. In theFormat Picture dialog box, in the left pane, click 3-D Format, and then in the 3-D Format pane, under Bevel, in the Top section, do the following:Click the button next to Top and then selectConvex (second row, third from the left)In the Width box, enter6 pt.In the Height box, enter6 pt.Also in the Format Shape dialog box, in the left pane, click Line Color, and then in the Line Color pane, do the following:ClickSolid line.Click the button next to Color, and then click MoreColors. In the Colors dialog box, on the Custom tab, enter Red:8, Green: 18, Blue:31.Alsoin theFormat Shape dialog box, in the left pane, click Line Style, and then in the Line Style pane, in Width box, enter0.75 pt.To reproduce two additional pictures and the cube, do the following:Select the picture on the slide. On the Home tab, in the Clipboard group, click the arrow next to Copy, and then click Duplicate.Repeat this step again for a total of three pictures. Position the pictures on the slide so that each one is visible.Select one of the duplicate pictures.Under Picture Tools, on the Format tab, in the Adjust group, click Change Picture. In the Insert Picture dialog box, select a picture, and then click Insert.Select the picture. Under PictureTools, on the Format tab, in the Size group, click the Size and Position dialog box launcher. In the Format Picture dialog box, resize or crop the image so that the height is set to 3.42” and the widthis set to 3.42”. To crop the picture, click Crop in the left pane, and in the Crop pane, under Crop position, enter values into the Height, Width, Left, and Top boxes. To resize the picture, click Size in the left pane, and in the right pane, under Size and rotate, enter values into the Height and Width boxes.Repeat steps 1 -3 to reproduce another picture. Select the picture that will appear on the top of the cube. Under Picture Tools, on the Format tab, in the Picture Styles group, click Picture Effects, point to 3-D Rotation, and then under Parallel, click Off Axis 1 Top (second row, third option from the left).Select the picture that will appear on the left side of the cube. Under Picture Tools, on the Format tab, in the Picture Styles group, click Picture Effects, point to 3-D Rotation, and then under Parallel, click Off Axis 1 Left (second row, first option from the left).Select the picture that will appear on the right side of the cube. Under Picture Tools, on the Format tab, in the Picture Styles group, click Picture Effects, point to 3-D Rotation, and then under Parallel, click Off Axis 1 Right (second row, second option from the left).Drag the pictures on the slide to create a cube. The edges of each picture may not line up exactly. To align the pictures as closely as possible, on the View tab, click Zoom. In the Zoom dialog box, click 400%, and then drag the pictures on the slide. Tip: To help more precisely place the pictures, select the picture that you want to move, then hold down the CTRL key and use the keyboard direction arrow keys.Press and hold SHIFT and select all three pictures on the slide. On the Home tab, in the Drawing group, click Arrange, and then click Group. On the Home tab, in the Editing group, click Select, and then click Selection Pane. Edit the name of the group in the Selection and Visibility pane, by double-clicking the group and then entering Cube Group.To reproduce the shadow effects on this slide, do the following:On the Home tab, in the Drawing group, click Shapes, and then under Rectangles click Rectangle (first option from the left). On the slide, drag to draw a rectangle. Select the rectangle. Under DrawingTools, on theFormat tab, in the Size group, do the following:In the Shape Height box, enter 3.42”.In the Shape Width box, enter 3.42”.On the Home tab, in the Drawing group, click the arrow next to Shape Fill, and then under Theme Colors click White, Text 1 (first row, second option from the left).On the Home tab, in the Drawing group, click the arrow next to Shape Outline, and then click No Outline. On the Home tab, in the bottom right corner of the Drawing group, click the Format Shape dialog box launcher. In the Format Shape dialog box, click 3-D Rotation in the left pane. In the 3-D Rotation pane, click the button next to Presets, and then under Parallel click Off Axis 1 Top (second row, third option from the left).Also in the Format Shape dialog box, click Shadow in the left pane, and then do the following in the Shadow pane: Click the button next to Presets, and then under Perspective click Below (first row, third option from the left).In the Transparency box, enter 72%.In the Size box, enter 110%.In the Blur box, enter 41 pt. In the Angle box, enter 115°.In the Distance box, enter 111 pt. On the Home tab, in the Drawing group, click Arrange, and then click Send to Back. Drag the rectangle under the cube so that it looks like the cube is floating.On the Home tab, in the Editing group, click Select, and then click Selection Pane. In the Selection and Visibility pane, press and hold CTRL and select both Cube Group and the rectangle. On the Home tab, in the Drawing group, click Arrange, and then do the following:Click Group.Point to Align, and then click Align to Slide.Point to Align, and then click Align Center.Point to Align, and then click Align Middle.To reproducethe animation effects on this slide, do the following:Select the cube.On the Home tab, in the Drawing group, Clipboard group, click the arrow next to Copy, and then click Duplicate.Clickone of the pictures in the new group of pictures and under Picture Tools, on the Format tab, in the group, click ChangePicture. In the Insert Picture dialog box, select another picture and click Insert. If necessary resize the picture – under PictureTools, on the Format tab, in the Size group, click the Size and Position dialog box launcher. In the Format Picture dialog box, resize or crop the image so that the height is set to 3.42” and the widthis set to 3.42”. To crop the picture, click Crop in the left pane, and in the Crop pane, under Crop position, enter values into the Height, Width, Left, and Top boxes. To resize the picture, click Size in the left pane, and in the right pane, under Size and rotate, enter values into the Height and Width boxes.Right-clickanother picture in the new group of pictures and repeat step 2.Note: If necessary, reposition the new pictures so they form a cube.Select the second cube. On the Animations tab, in the Animations group gallery of animation effects, under Entrance,click Fade.In the Animation Pane, click the arrow next to the animation, and then click Timing. In the Fade dialog box, on the Timing tab, in the Delay box, enter 0.5 seconds, and then click OK.Select both cubes. On the Home tab, in the Drawing group, click the arrow below Arrange, and under PositionObjects, point toAlign, and do the following:SelectAlignCenter.SelectAlignMiddle.Repeat steps 1 through 6 two more times to reproduce the third and fourth cube, which improves the animation effect.To reproduce the background effects on this slide, do the following:On the Design tab, in the Background group, click BackgroundStyles, and then select Style 8 (second row, fourth from the left). Note: If this action is taken in a PowerPoint presentation containing more than one slide, the background style will be applied to all of the slides.
  • 2 DEFINlTIONS2.1 International definitionsQuality assurance. All those planned and systematic actions necessary to provide adequate confidencethat a product or service will satisfjl given requirements for quality(lo).Trueness: closeness of the agreement between the average value obtained from a large series of testresults and an accepted reference value(11).Precision: closeness of agreement between independent test results obtained under prescribedconditions(l2).Bias: difference between the expectation of the test results and an accepted reference value(ll).Accuracy: closeness of the agreement between the result of a measurement and a true value of themeasurand(l3).Note 1. Accuracy is a qualitative concept.Note 2. The termprecision should not be used for accuracy.Error: result of a measurement minus a true value of the measurand(13).Repeatability conditions. conditions where independent test results are obtained with the same methodon identical test items in the same laboratory by the same operator using the same equipment within shortintervals of time(11).Uncertainty of measurement: parameter, associated with the result of a measurement, that characterisesthe dispersion of the values that could reasonably be attributed to the measurand(l4).Note I. The parameter may be, for example, a standard deviation (or a given multiple of it), or thehalf-width of an interval having a stated level of confidence.Note 2. Uncertainty of measurement comprises, in general, many components. Some of thesecomponents may be evaluated from the statistical distribution of results of a series of measurementsand can be characterised by experimental standard deviations. The other components, which canalso be characterised by standard deviations, are evaluated from assumed probability distributionsbased on experience or other information.Note 3. It is understood that the result of a measurement is the best estimate of the value of ameasurand, and that all components of uncertainty, including those arising from systematic effects,such as components associated with corrections and reference standards, contribute to thedispersion.Traceability: property of the result of a measurement or the value of a standard whereby it can be relatedto stated references, usually national or international standards, through an unbroken chain of comparisonsall having stated uncertainties(13).0 1995 IUPAC, Pure and Applied Chemistry, 67,4654 WP ON HARMONIZATION OF QUALITY ASSURANCE SCHEMES FOR ANALYTICAL LABSReference material: material or substance one of whose property values are sufficiently homogeneous andwell established to be used for the calibration of an apparatus, the assessment of a measurement method, orfor assigning values to materials(l3).Certified reference material: reference material, accompanied by a certificate, one or more of whoseproperty values are certified by a procedure which establishes its traceability to an accurate realisation ofthe unit in which the property values are expressed, and for which each certified value is accompanied byan uncertainty at a stated level of confidence(l3).
  • 2.1 International definitionsQuality assurance. All those planned and systematic actions necessary to provide adequate confidencethat a product or service will satisfjl given requirements for quality(lo).Trueness: closeness of the agreement between the average value obtained from a large series of testresults and an accepted reference value(11).Precision: closeness of agreement between independent test results obtained under prescribedconditions(l2).Bias: difference between the expectation of the test results and an accepted reference value(ll).Accuracy: closeness of the agreement between the result of a measurement and a true value of themeasurand(l3).Note 1. Accuracy is a qualitative concept.Note 2. The termprecision should not be used for accuracy.Error: result of a measurement minus a true value of the measurand(13).Repeatability conditions. conditions where independent test results are obtained with the same methodon identical test items in the same laboratory by the same operator using the same equipment within shortintervals of time(11).Uncertainty of measurement: parameter, associated with the result of a measurement, that characterisesthe dispersion of the values that could reasonably be attributed to the measurand(l4).Note I. The parameter may be, for example, a standard deviation (or a given multiple of it), or thehalf-width of an interval having a stated level of confidence.Note 2. Uncertainty of measurement comprises, in general, many components. Some of thesecomponents may be evaluated from the statistical distribution of results of a series of measurementsand can be characterised by experimental standard deviations. The other components, which canalso be characterised by standard deviations, are evaluated from assumed probability distributionsbased on experience or other information.Note 3. It is understood that the result of a measurement is the best estimate of the value of ameasurand, and that all components of uncertainty, including those arising from systematic effects,such as components associated with corrections and reference standards, contribute to thedispersion.Traceability: property of the result of a measurement or the value of a standard whereby it can be relatedto stated references, usually national or international standards, through an unbroken chain of comparisonsall having stated uncertainties(13).0
  • 2.2 Definitions of terms specific to this documentInternal quality control: set of procedures undertaken by laboratory stafF for the continuous monitoringof operation and the results of measurements in order to decide whether results are reliable enough to bereleased.Control material: material used for the purposes of internal quality control and subjected to the same orpart of the same measurement procedure as that used for test materials.Run (analytical run): set of measurements performed under repeatability conditions.Fitness for purpose: degree to which data produced by a measurement process enables a user to maketechnically and administratively correct decisions for a stated purposeAnalytical system: range of circumstances that contribute to the quality of analytical data, includingequipment, reagents, procedures, test materials, personnel, environment and quality assurance measures.
  • The performance of a method routinely used in a laboratory must be monitored continuouslyby quality control techniques in order to detect any change in accuracy or precision and takecorrective action. Quality control is of two kinds: internal quality control, the proceduremaking use of results of only one laboratory for quality control; and external quality controlin which the results of several laboratories which analyse the same sample(s) are used.
  • Two major types of errors may occur in a laboratory:Random errors that arise due to inadequate control on pre-analytical variables, patientidentity, sample labelling, sample collection, handling and transport, measuring devices etc.Systemic errors that occur due to inadequate control on analytical variables; e.g. due to errorin calibration, impure calibration material, unstable/ deteriorated calibrators, unstable reagentblanks etc.The performance of a method routinely used in a laboratory must be monitored continuouslyby quality control techniques in order to detect any change in accuracy or precision and takecorrective action. Quality control is of two kinds: internal quality control, the proceduremaking use of results of only one laboratory for quality control; and external quality controlin which the results of several laboratories which analyse the same sample(s) are used.
  • It is very difficult to establish effective methods for monitoring and controlling preanalytical variables because may of the variables are outside the laboratory areas.  Requires the coordinated effort of many individuals and hospital departments
  • CONTROL OF THE ANALYTICAL QUALITY USING STABLE CONTROL MATERIALSThe performance of analytical methods can be monitored by analyzing specimens whose concentrations are known and then by comparing the observed values with known values.The known values are usually represented by an interval of acceptable values, or upper and lower limits for control (control limits)When the observed values fall within the control limits – analysis is working properlyWhen the observed value fall outside the control limits the analyst should be alerted to the possibility of problems in the analysis. A control also has a known amount of an analyte but is used to monitor the precision and accuracy of an assay method once it has been calibrated.Use 2 or three levels of controls Include with patient samples when performing a testUsed to validate reliability of the test systemTypes of Control MaterialsAssayedmean calculated by the manufacturermust verify in the laboratoryUn-assayedless expensivemust perform data analysis“Home made” or “In-house” pooled sera collected in the laboratorycharacterizedpreserved in small quantities for daily use
  • External QC programme: The concerned laboratory is provided with vials of controlswithout reference values for analysis under the conditions of that lab. The results obtainedwould be sent to the reference laboratory for verification. Internal QC programme is suitableto determine the reproducibility of result (precision). External QC programme is useful toassess the closeness of a result to the actual value (accuracy).If the result of the presently used method widely deviates from the majority of the othermethods which agree with one another, the method should be immediately replaced byanother. Revaluation of calibration standards, reagents, pipettes and measuring devices mustbe considered in case of any kind of deterioration.
  • Internal quality control (QC) programmemay be formulated considering the followingpoints:1. Clinical correlation of test with the disease the patient is suspected to be sufferingfrom.2. Within-assay variation: The same sample is analysed twice during an assay and theoutcome noted. Results should be identical if no error exists; a large variationsuggesting one or more errors.3. Intra-laboratory duplicates: Samples may be analysed in duplicates for 2 days andreproducibility of the four values checked.4. The results of a test may be compared with the results of the same tests previouslyconducted on the patient. The values are expected to increase with disease progressionand vice versa. A deviation from this pattern indicates error.

Quality control ppt BIOCHEMISTRY Quality control ppt BIOCHEMISTRY Presentation Transcript

  • Three principles of clinical lab
  • What is Quality? Quality defined as conformance to the requirements of users or customers
  • Total quality management of the clinical lab
  • Quality Control Emphasizes statistical and nonstatistical check procedures Able to detect the problems early enough to prevent their consequences Techniques and procedures that monitor performance parameters
  • Prerequisite for an effective lab service Promotion of quality control and continuous improvement of the total testing process, including preanalytical and postanalytical phases
  • Steps in obtaining a laboratory test
  • Lab testing processes and their potential errors Test ordering Specimen acquisition Analytical measurement Test reporting Test interpretation
  • Test ordering Inappropriate test Handwriting not legible Wrong patient identification Specimen acquisition Analytical measurement Test reporting Test interpretation Lab testing processes and their potential errors
  • Test ordering Specimen acquisition Incorrect tube Incorrect patient identification Inadequate volume Collected at wrong time Improper transport conditions Analytical measurement Test reporting Test interpretation Lab testing processes and their potential errors
  • Test ordering Specimen acquisition Analytical measurement Instrument not calibrated correctly Specimen mix-up Incorrect volume of specimen Interfering substance present Instrument precision problem Test reporting Test interpretation Lab testing processes and their potential errors
  • Test ordering Specimen acquisition Analytical measurement Test reporting Wrong patient identification Report not legible Report delayed Transcription error Test interpretation Lab testing processes and their potential errors
  • Test ordering Specimen acquisition Analytical measurement Test reporting Test interpretation Interfering substance not recognized Specificity of the test not understood Precision limitations not recognized Analytical sensitivity not appropriate Previous values not available for comparison Lab testing processes and their potential errors
  • Elements of a QA/QC Program Commitment Facilities and resources Technical competence Technical procedures Problem solving mechanisms
  • Quality Control: Technical Procedures Control of preanalytical variables Control of analytical variables Control of analytical quality using statistical methods and control charts
  • Test requests Patient preparation Patient identification Specimen acquisition Specimen transport Specimen processing Specimen distribution Preparation of work lists Control of preanalytical variables
  • Patient Identification The highest frequency of errors occurs with the use of handwritten labels and request forms. The use of bar code technology has significantly reduced ID problems. Turnaround time Delayed and lost test requisitions, specimens and reports can be major problems for labs. Recording of the actual times of specimen collection, receipt in the lab and reporting of results with use of computers will solve these problems.
  • Manual entry of data even with the double checking of results Computerization will reduce this type of transcription error. Lab tests are affected by many factors, such as, recent intake of food, alcohol, or drugs; smoking, exercise, stress, sleep, posture during specimen collection The lab must define the instructions and procedures compliance with these instructions can be monitored directly efforts should be made to correct non compliance
  • • Prolonged tourniquet application. • Blood collection from an arm into which an intravenous infusion is running. Specimen Collection • To monitor and control these problems, specially trained lab team assigned to specimen collection • The identification of the person collecting a specimen should be maintained • Clinicians should be encouraged to report clinically inconsistent results. Hemolysis during blood collection
  • Analytical methodology Standardization Calibration procedures Documentation of analytical protocols Monitoring of critical equipment and materials Control of analytical variables
  • • Water quality • Calibration of volumetric glassware and pipets • Stability of electrical power • Stability of temperature of heating baths, refrigerators, freezers and centrifuges Many analytical variables
  • • Procedure name • Clinical significance • Principle of method • Specimen of choice • Reagents and equipments • Procedure • Reference values • Comments • References The procedure Manual should contain the following
  • • Values cover medical decision points • Similar to the test specimen (matrix) • Available in large quantity • Stored in small aliquots • Ideally, should last for at least 1 year Using stable ‘controls’
  • • Reconstitute lyophilized material carefully & strictly as per label direction • Frozen sample to be thawed properly. After attaining room temp., mix slowly by inversion and then use. • Storage temperature to be strictly followed Precautions to be followed
  • Assayed Unassayed Level 1 , 2 and 3
  • • Have a known concentration of the substance (analyte) being measured • Used to adjust instrument, kit, test system in order to standardize the assay • Sometimes called a standard, although usually not a true standard • This is not a control Using ‘Calibrators’
  • Day to day internal QC programme Is a most useful tool For maintenance of long term Consistency ( Accuracy ) control Long term Precision control of analytical method Internal Q C monitors a single lab
  • Provides independent validation of internal QC program Gives valid estimation of long term accuracy of analytical system Compares performance of different labs
  • Control of analytical quality using statistical methods and control charts Statistical methods Mean, SD, CV Accuracy Precision Control charts Levey-Jennings Control Chart Westgard multirule chart Shewhart SD control chart
  • l Levey-Jennings Control Chart
  • Trends & Shifts
  • CUSUM Control Chart
  • Control of analytical quality using patient data Clinical correlation of test results Correlation with other lab tests
  • •Tietz test book of clinical Biochemistry •Varley •Kaplan •Internet References