PEPFAR Quality Control and Method Validation Activity 12 Job Aid 3: Applying Comparison Report Information

134 Job Aid 3: Applying Comparison Report Information 1216 Report Information Significance Valid estimate of your laboratory's ability to obtain Comparison of your mean to the same average (mean) value for a specific sample the peer group's as the peer group performance Be aware that the SDI measured by the peer group is divided by a smaller SD value than that of the all-lab's SD, thus producing a smaller SDI value. Helpful when investigating discrepancies between your laboratory's performance to your peer's values Helpful to compare when the number of laboratories Comparison of your mean to reporting for your specific method is small (N < 5) the all-lab group's mean Can investigate PT problems -you can determine if the method you are using has an overall significant bias that may be reflected in the PT samples and not by a problem specific to your laboratory Your laboratory's mean Are you reporting the right method and are included compares well to all-lab with the right peer group? group's mean but not well to Is the peer data valid (e.g. small number of labs the peer's mean which includes 1 or 2 aberrant results)? Excellent source for determining the usual SD for your method By comparing each month's SD to the usual SD, you can monitor unexpected increases in imprecision Monitor shifts in SDI or CVI that occur over a period of time Historical Data Review If your mean value is drifting and the mean values from peer and all-lab groups are drifting in the same direction, then the problem is probably due the control material itself. If however, your mean is drifting while the mean values reported for the peer and all-lab groups remain constant, then the problem is within your laboratory Quick comparison of method performance in the Cumulative Data Review current month relative to the mean and SD since started using the control An alert to a statistical difference between your CVI Flag Present laboratory's CV and the CV obtained by the peer group An alert to a statistical difference between your SDI Flag Present laboratory's mean and the mean value obtained by the peer group HILS1746 Effective Date: 12/6/2016