The ATS 1994 Update recommends that spirometry data collection programs be subject to a Quality Control review to insure the continued collection of valid data. The basis for this recommendation stems from the National Lung Health Study which demonstrated that a consistently applied quality Control program resulted in a significantly higher yield of valid data.
Since data validity results in increased test sensitivity and specificity, it follows that any screening and surveillance program using Quality Control will reduce its risk of obtaining false positive and negative data. The program requires a sample of spirometry records be sent to Palmer Associates Inc. Overread Center on a periodic basis for review and evaluation. Consistent procedural errors that invalidate the data can be identified with corrective measures suggested to that technician.
A performance report is sent to each person submitting records. Summary performance records by person and by site are submitted to management along with errors that occurred and how to correct the errors. Companies using this service have improved their data quality Success Rates significantly, for example by going from 78.3% to 95.6%.
The basic document around which all Quality Control decisions are made is a written Standard Operating Procedure Manual (SOP). This document, along with a video showing the steps to be followed, provides a blueprint for standardizing test procedures between personnel and various sites. Such guidelines increase the sensitivity and specificity of the program. Employees appreciate the easy to follow format of these SOP manuals, definitely user friendly.