This website is intended for healthcare professionals only.

Hospital Healthcare Europe
Hospital Healthcare Europe

Making medicine safe: patient safety in the laboratory

Elizabeth A Wagar
1 January, 2008  

Elizabeth A Wagar
Professor and Vice Chair
Laboratory Director UCLA Clinical Laboratories
Los Angeles
California, USA

The rapid evolution of the clinical laboratory in providing information for patient care has been dramatic. Fifty years ago, most laboratories were performing less than 20 different tests on a regular basis. Now, even small laboratories perform hundreds of tests using multiple instruments interfaced with advanced computer systems. With this rapid development, opportunities for errors have increased, resulting in quality management problems for clinical laboratories, physicians and patients.

The landmark publication that first raised the problem of patient safety problem in the USA, To Err is Human: Building a Safer Health System, was published by the Institute of Medicine in 2000.(1) Since then, a global effort has been implemented to improve patient safety. In 2004, the World Health Organization (WHO) launched the World Alliance for Patient Safety.(2) Other countries, including Denmark and France, quickly developed initiatives pertinent to their healthcare systems.(3) The USA support multiple types of patient safety projects through the Agency for Healthcare Research and Quality (AHRQ).(4) The Joint Commission for the Accreditation of Healthcare Organizations (JCAHO) has made patient safety standards an important component of their accreditation process.(5) The College of American Pathologists (CAP) has provided laboratory-specific benchmarks for patient safety through their Q-TRACKS™ and Q-PROBES™ efforts.(6)

Lab errors
Laboratory errors can be classified in several ways. Historically, most have been classified by cause, phase of testing, responsible party and impact on the patient.(7) Errors can occur before testing (wrong specimen collection), as part of the analytical test procedure itself or after testing (including the test report). These are referred to as preanalytical, analytical and postanalytical errors. A number of CAP Q-PROBESTM and Q-TRACKSTM have focused on pre- and postanalytical errors, including wristband identification errors and reporting of life-threatening or critical laboratory results.(8,9) A common conclusion is that many laboratory errors occur outside of the control of laboratory services.(10,11)

Another error classification is by cause, such as identification errors.(12) Examples of errors that can occur with laboratory specimens are unlabeled specimens, specimens that are mismatched to the accompanying requisitions and mislabeled specimens (sometimes referred to as “wrong blood in tube”) because the blood in the tube belongs to a different patient than that indicated on the tube label. In a study conducted at UCLA to assess the value of sequential patient safety projects, including conversion to 24/7 phlebotomy, implementation of an electronic event reporting system and introduction of processing automation, trend analysis confirmed a reduction in all three types of specimen identification errors.(12)

Additional studies have examined the clinical impact of laboratory errors on patient care. By reviewing corrected reports in clinical microbiology testing, it was determined that 6.7% were associated with adverse clinical impact, such as delayed, unnecessary or inappropriate therapy, or increased level of care.(13) Clinical impact assessment allows laboratories to identify the errors which should be
immediately addressed for adequate patient care.

In one recent classification scheme, cognitive psychology concepts were applied to categorise preventable human errors in the laboratory as cognitive (“mistakes”) or noncognitive (“slips”).(14) Cognitive errors occur due to lack of knowledge and can be addressed by training and counselling. Noncognitive errors occur due to lapses in expected behaviour. With noncognitive errors, correction of processes or procedures is more likely to be successful than training. For example, a Gram stain that is incorrectly reported because the technologist does not know how to stain the slide would be a cognitive error, which could be corrected by training and education. An incorrectly reported Gram stain that occurred because the technologist was distracted by other tasks would be a noncognitive error, best corrected by limiting work distractions.


Most laboratory professionals are sincerely interested in avoiding human errors. Although the “name, shame and blame” approach is not necessarily a desirable tool for error reduction, some sort of employee accountability is required in most work environments. In a “just culture” environment, human errors are categorised as:

  • Unintended human error.
  • At-risk behaviour.
  • Reckless behaviour with appropriate management interventions for each category.(15)

Thus, managers are provided with tools for appropriate follow-up and accountability based on the means by which an error occurred.

The laboratory provides important models for examining patient safety. Understanding how laboratory errors are classified and how they can be reduced is an important component of patient safety. Many errors occur outside the laboratory, yet on a continuum with the test ordering process. An example is the incorrect labelling of a specimen in a clinic, resulting in “wrong” laboratory results. This may subsequently result in inappropriate therapy or additional diagnostic testing. Also, an understanding of why people make mistakes, as in the cognitive vs noncognitive example, provides insights into the potential for errors in other healthcare settings. Ultimately, it takes an entire healthcare system to produce correct laboratory results and improve patient safety. Enhanced communication with physicians, nurses and other healthcare professionals is essential. Whether a laboratory wishes to reduce mislabeled specimens or better communicate critical or life-threatening laboratory results, the entire system must work effectively as a whole for healthcare to become a safe haven for patients.


  1. Institute of ­Medicine. To err is human: building a safer health system. Washington (DC): National Academy Press; 2000.
  2. WHO. Patient safety.
  3. Operation life.
  4. Agency for Healthcare Research and Quality. Medical errors & patient safety.
  5. The Joint Commission. Patient safety.
  6. Howanitz PJ. Arch Pathol Lab Med 2005;129(10):1252-61.
  7. Bonini P, et al. Clin Chem 2002;48(5):691-8.
  8. Wagar EA, et al. Arch Pathol Lab Med 2007;131(1):44-9.
  9. Howanitz PJ, et al. Arch Pathol Lab Med 2002;126(7):809-15.
  10. Plebani M. Clin Chem Lab Med 2006;44(6):750-9.
  11. Plebani M, et al. Clin Chem 1997;43(8Pt1):1348-51.
  12. Wagar EA, et al. Arch Pathol Lab Med 2006;130(11):1662-8.
  13. Yuan S, et al. J Clin Microbiol 2005;43(5):2188-93.
  14. Astion ML, et al. Am J Clin Pathol 2003;120(1):18-26.
  15. Marx D. Patient safety and the “just-culture”: a primer for healthcare executives. April 2001.