Clinical Chemistry and Hematology Laboratories

Cytohematology Proficiency Testing of March 2001

Laboratories holding a permit for the category Cytohematology (Limited or Diagnostic) are required to participate in one glass slide test event per year. An overall event score of less than 80%, or a score of less than 80% on two or more slides, is considered unsatisfactory.

This proficiency test was shipped on 12 March 2001 with a due date of 23 March 2001. Reports were issued on 30 April 2001 . Proficiency test results were submitted by 451 laboratories. The participant median value, expected range (95 percentile range as established by robust analysis of results obtained from participant results), and the participant range minus outliers were evaluated for each white-cell type. Error points were reported for responses falling outside the expected range. Results which exceeded the 97 percentile range were assigned additional error points. Error points were assigned if the WBC differential count substantially deviated from 100 ( one error point given for each cell reported outside the range 99-101).

Participant responses for red cell morphology ( none, slight, moderate, and marked ) were reported as a percentage of total response. The presence or absence of other red cell, white cell, platelet or miscellaneous findings was also expressed in percentage format. Error points were reported for responses falling outside the expected range or result.

Five glass slides were distributed: