A 2-year study of Gram stain competency assessment in 40 clinical laboratories.
We used a computer-based competency assessment tool for Gram stain interpretation to assess the performance of 278 laboratory staff from 40 laboratories on 40 multiple-choice questions. We report test reliability, mean scores, median, item difficulty, discrimination, and analysis of the highest- and lowest-scoring questions. The questions were reliable (KR-20 coefficient, 0.80). Overall mean score was 88% (range, 63%-98%). When categorized by cell type, the means were host cells, 93%; other cells (eg, yeast), 92%; gram-positive, 90%; and gram-negative, 88%. When categorized by type of interpretation, the means were other (eg, underdecolorization), 92%; identify by structure (eg, bacterial morphologic features), 91%; and identify by name (eg, genus and species), 87%. Of the 6 highest-scoring questions (mean scores, > or = 99%) 5 were identify by structure and 1 was identify by name. Of the 6 lowest-scoring questions (mean scores, < 75%) 5 were gram-negative and 1 was host cells. By type of interpretation, 2 were identify by structure and 4 were identify by name. Computer-based Gram stain competency assessment examinations are reliable. Our analysis helps laboratories identify areas for continuing education in Gram stain interpretation and will direct future revisions of the tests.
Goodyear
Nancy
N
Department of Laboratory Medicine, University of Washington, Seattle 98195, USA.
Kim
Sara
S
Reeves
Mary
M
Astion
Michael L
ML
D003194:Computer-Assisted Instruction / Q000379:methods*; D005840:Gentian Violet; D006090:Gram-Negative Bacteria / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000302:isolation & purification; D006801:Humans; D007753:Laboratories / Q000592:standards; D013677:Medical Laboratory Science / Q000193:education / Q000592:standards*; D010619:Phenazines; D011361:Professional Competence / Q000592:standards*; D013194:Staining and Labeling / Q000592:standards*; D011795:Surveys and Questionnaires / Q000592:standards; D014481:United States
C035863:Gram's stain; D010619:Phenazines; D005840:Gentian Violet