Commonalities and differences in the perception of competence among three levels of medical laboratory personnel were assessed through a survey of 100 educators, chief technologists, and working technicians. Respondents rated medical technologists (MTs), medical laboratory technicians (MLTs), and certified laboratory assistants (CLAs) on 270 tasks in six areas concerning the clinical laboratory. Responses to a Likert-type scale were analyzed by multivariate statistical analysis. It was found that educators, chief technologists, and MLT graduates rated the medical technology the same; chief technologists rated MLTs lower than did educators or graduates; and chief technologists also rated CLAs lower. Specific conclusions relating to competence in hematology are as follows: educators perceived MTs to be more competent in hematology than did chief technologists or graduates; chief technologists rated MLTs and CLAs less competent than MTs and MLTs in hematology; chief technologists rated MTs, MLTs, and CLAs at three levels (in descending order) of competence in hematology; and MLT graduates rated themselves as competent as MTs and more competent than CLAs in hematology. Biographical data submitted by respondents show that slightly over half of the educators and chiefs had more than 10 years of experience in laboratory medicine, and almost half of MLT graduates worked in hospitals of more than 200 beds. Correlations between the 1973 "Position Paper" of the American Society for Medical Technology, the 1978 "Statements of Competence," and the 1980 "Course Outline" of ASMT are examined. A bibliography is appended. (SW)