The Importance of Ensuring Validity and Accuracy of Testing in Lecture and in the Clinical Lab
Achieving, maintaining and improving accuracy, timeliness and reliability are major challenges for health laboratories. Countries worldwide committed themselves to build national capacities for the detection of, and response to, public health events of international concern when they decided to engage in the International Health Regulations implementation process.
Medical Laboratory Technology also called Clinical laboratory science is an allied health profession which is concerned with the diagnosis, treatment and prevention of disease through the use of clinical laboratory tests. It is a combination of the techniques along with the application of theoretical knowledge to perform complex procedures on tissue specimens, blood samples and other body fluids. They look for bacteria, parasites, and other microorganisms; analyze the chemical content of fluids; match blood for transfusions; and test for drug levels in the blood that show how a patient is responding to treatment. The tests which are performed provide critical information enabling physicians to diagnose, treat and monitor a patient’s condition.With increasing automation and the use of computer technology, the work of technologists and technicians has become less hands-on and more analytical. The complexity of tests performed, the level of judgment needed, and the amount of responsibility workers assume depend largely on the amount of education and experience they have. Clinical laboratory technologists usually do more complex tasks than clinical laboratory technicians do. Medical technologists have more training and job responsibilities. They perform complex tests such as microscopic examinations of tissues, blood and other body fluids to detect evidence of disease and detect the presence of bacteria, fungi, parasites etc and chemical tests to determine blood cholesterol levels. They also match blood samples for transfusions and test drug levels in blood to determine how patients are responding to medications. They are often responsible for making sure that testing is done accurately. In some labs, technologists conduct research under the supervision of medical researchers.
The standards used by the measurement profession are contained in the Standards of Educational and Psychological Measurement, published in 1999 by a joint committee of three influential and important organizations: the American Association of Educational Research (AERA), the American Psychological Association (APA), and the National Council on Measurement in Education (NCME). These Standards are used by all professionals who construct tests or other measurement instruments (e.g., performance assessments and portfolios), especially in a high stakes context such as teacher certification. When high stakes decisions are challenged in the courts, these Standards serve as the legal standard to which the assessment process and results are held. Because of these two critically important applications, the Standards outweigh in importance and credibility all textbooks and scholarly literature in defining the requirements of high quality assessment (Yoon, B., & Resnick, L. B., 1998). They are the standards that set the bar. Even though the word “accuracy” appears often in the literature, particularly textbooks, it is not a viable substitute for “validity.” James Popham, for example, who has written many popular assessment textbooks and is one of the most respected and prolific authors in the measurement field, uses the term “accuracy” for explanatory purposes but them makes the following statement about the necessity to use the real language (i.e., “validity”) of measurement in the world of practice (Littlefield, R. S., 1983).
To summarize, there are many other standards organizations, and many examples of laboratory standards. Some countries have established national laboratory quality standards that apply specifically to laboratories within the country. Some laboratory standards apply only to specific areas in the laboratory or only to specific tests. The World Health Organization has established standards for some specific programs and areas. quality management is not new; it grew from the good works of innovators who defined quality over a span of 80 years. Quality management is as applicable for the medical laboratory as it is for manufacturing and industry.
Littlefield, R. S. (1983). Competitive live discussion: The effective use of nonverbal cues. The Forensic, 69, (2), 14-20.
Wightman, L. F., & Muller, D. G. (1990). An analysis of differential validity and differential prediction for black, mexican american, hispanic, and white law school students. LSAC research report series No. LSAC-R-90-03)
Yoon, B., & Resnick, L. B. (1998). Instructional validity, opportunity to learn and equity: New standards examinations for the california mathematics renaissance No. CSE-TR-484)