PEPFAR Quality Control and Method Validation Activity 5 Worksheet 4: L-J Chart 4

Worksheet 4: L-J Chart 4 507 Effective Date: 12/6/2016 HILS1746 Directions: Based on the information provided by the L-J chart, determine the assigned mean and assigned SD in umol/L. Based on your visual examination of the chart, approximate the observed mean and observed SD in umol/L. Fill in the blank spaces with your responses. Draw the Gaussian curve using the assigned mean and assigned SD on the L-J chart. Draw another Gaussian curve using the observed mean and observed SD. Label the following sections of the curves as: true accept, false reject, false accept. Refer to 1: Possible Outcomes for assistance. Cape Clinic Laboratory Creatinine (umol/L) L-J Chart for Control XYZ (exp 30/11/XX) on Illustra Chemistry Analyzer (serial # 123) X assigned SD assigned X observed SD observed 99.0 +4SD 96.0 + 3SD ........................................ .............. ........... ..... 93.0 + 2SD .................. 90.0 + 1SD ..... 87.0 X ................ 84.0 -1SD 81.0 2SD 78.0 3SD 75.0 -4SD Run 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 ..................... Value 93 84| 90 93 88 86 88. 95 92 94 88 90 89 87 91 90 94 88 97 90| 91 95 90 85 91 94 89 91 85 89 48 49 Worksheet 4: L-J Chart 4 507 4 Using the assigned mean, what are the values (umol/L) for + 2SD control limits? Using the observed mean, what are the values (umol/L) for + 2SD? We expect that 68% of the measurements lie between -1SD and +1SD control limits when the assigned = observed on the chart. However, on this chart where the Mean assigned # Mean observed, 68% of the data points lie between what control limits? 95% of the data points lie between what control limits? What QC Rule(s) are violated on the chart when the assigned mean +observed mean Run Number Rule(s) Violated Interpret the Control Measurement (true accept, false reject, or false accept) The data points used in Chart #4 are identical to the data points used in Chart #1 (a stable population normally distributed). When compared to Chart #1, there is an increase / decrease in rule violations and this is because ...... Circle one If the next measurement (Run #31) is 81 umol/L, what type of outcome would be given to that value? Refer to Job Aid 1: Possible Outcomes, if needed. Draw the Gaussian curves of the assigned and observed populations on the back of the worksheet. Label the following sections of the curves as: true accept, false reject, false accept. HILS1746 Effective Date: 12/6/2016