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Clinical Chemistry and Hematology Laboratories

Cytohematology - Cell Identification

• Glass Slide Program
• Photographic Images

Other areas of Hematology

• Cellular Hematology
• Coagulation
• Proficiency Testing in Hematology

Cytohematology is the study of the cellular components of blood cells. The three main groups of blood cells observed are the thrombocytes (platelets), erythrocytes (red blood cells), and leukocytes (white blood cells). Parasites may also be observed during microscopic examination of the blood smear.

 

The cytohematology laboratory of the Wadsworth Center maintains a collection of approximately 7000 slides of peripheral blood smears from nearly 200 different cases. Study slides are available for laboratory use. We design and carry out the New York State Proficiency Testing Programs in the area of cytohematology and cell identification. Two programs are conducted:  The photographic image program and the glass slide program.

Category Description

Laboratories performing manual screening or manual diagnostic differentials must apply for this category

Proficiency Test Frequency

Five photographic images are submitted to participating laboratories three times per year for cell identification. Laboratories are also required to participate in at least one glass slide event per year. We distribute stained glass slides to participating laboratories during the test year.

Quality Control of Samples

Photographic images are prepared at the Wadsworth Center. Glass slides are prepared and stained from blood obtained from Wadsworth Center staff or local hospitals. Stained slides for use in the program may also be submitted by participating laboratories. Bloods used are received with a CBC and differential from the referring laboratory. A brief history as well as any additional tests, if available, are also obtained to verify diagnosis. Known infectious samples are not used.

 

Target Values

Acceptable responses are determined by all-participant responses. Acceptable response(s) for cell identification reflect 80% or greater agreement of the participating laboratories. Target values for glass slides are established based on raw data collected from laboratories. Subsequent to a robust analysis, outliers are removed and a mean for each cell type is calculated. Percentile cutoffs are established for each slide after a review of the raw data.

Acceptable range

Acceptable limits are established using criteria specified by CLIA '88 regulations, for Cell Identification 80% or greater consensus on identification is required. Results identical to correct classification(s) are scored as 100%. Any incorrect classification is considered unsatisfactory and receives a score of 0%. Acceptable performance is determined by the following CLIA '88 criteria.