College of American Pathologists
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  PAP/NGC Program Review





cap today

May 2003
Special Section

A sweep for missing slides

Marianne Prey, MD

The Cytopathology Committee is in search of missing survey
slides distributed to participants in the Interlaboratory Comparison Program in Gynecologic Cytopathology, or Pap program.

The loss of Pap program slides and slidesets now approaches 10 percent. This loss of slides affects program participants by delaying survey shipments, and it limits the CAP's ability to accept new laboratories that want to participate.

The Pap program is unique in that it takes years to complete the validation process for a single survey slide to fulfill proficiency testing requirements. The slides for this program are truly one of a kind. Unlike slides used in the CAP Surveys or PIP programs, Pap program slides cannot be kept by participating labs.

CAP staff cytotechnologists first examine donated slides to determine whether the slides are of good technical quality and an excellent example of the reference interpretation. Once that is established, at least three Board-certified pathologists from the Cytopathology Committee review the slides. The committee members must agree on the exact target interpretation, and this must agree with the submitted biopsy interpretation (if LSIL or higher) before the slide can be accepted into the program as an educational slide.

To move from the educational to graded category, a slide must be field validated. Validation criteria are as follows:

  • At least 20 laboratory participants must submit a response on the slide.
  • The percentage of participant responses in the correct selection series must be at least 90 percent.
  • The standard error of this percentage cannot exceed 0.05.
  • The interpretations submitted on slides in the 100 series must show at least 50 percent concordance with the exact reference interpretation. Interpretations submitted on SIL slides must show at least 70 percent concordance with the exact reference interpretation.

Survey slidesets are mailed only four times a year; thus it takes years of constant circulation to generate statistics for validation. If even a single slide is not returned, years of committee and participating laboratory efforts are lost. More important, these slides are loaned to the CAP with the understanding that the CAP will track the slides and be able to retrieve them for the donor laboratory if they are needed for review for patient care or litigation. If a laboratory fails to return slides, it is not only hindering the success of the program but also may be detrimental to patient care.

Slidesets must be returned using a traceable shipping method within seven working days as stated in the kit instructions. Continuing medical education certificates will not be released until CAP staff receives the slideset. The laboratory will not receive its next slideset until the outstanding slideset is returned. Failure to comply will make the laboratory ineligible for participation in the Interlaboratory Comparison Program in Cervicovaginal Cytopathology. It is important to remember that laboratories must participate in a glass slide proficiency testing program to meet CAP Laboratory Accreditation Program requirements for cytopathology.

Please take the time now to respond to missing slide return requests. Search every possible place where slides may be. Send everything you find to the CAP as soon as possible. Call the CAP customer service department at 800-323-4040, option 3, if you have questions or to request shipping materials.