A review of the literature

Turnaround times in the laboratory: A review of the literature

Manor, Pamela G

OBJECTIVE: To conduct a review of the literature for current information pertaining to turnaround times in the clinical laboratory. To evaluate the methods previously used for improving turnaround times and provide a reference for laboratories.

DESIGN: The literature was reviewed for information related to turnaround times in the laboratory. Information was limited to literature published from 1989 to present in order to cover the more technological innovations.

RESULTS: Several methods have been used in recent years for the improvement of turnaround times in the clinical laboratory. Among these are pneumatic tubing systems, satellite laboratories, pointof-care testing, and computer technology.

CONCLUSIONS: There is still the need for faster turnaround times. Technological advances are enabling laboratories to better meet these needs leading to improved user satisfaction.

ABBREVIATIONS: POCT = point of care testing; TAT = turnaround time.

INDEX TERMS: hospital laboratories; turnaround time.

Clin Lab Sci 1999;12(2):85

The turnaround time (TAT) in laboratory testing has long been established as a key factor in user satisfaction. It has been stated that the TAT is the most noticeable sign of performance to clinicians, drawing comments immediately when prolonged and going unnoticed when adequate.l A faster TAT generally induces more satisfaction of laboratory service and a slower TAT is associated with dissatisfaction. The manner in which physicians use laboratory data generally dictates that the faster the TAT the better. 2 That is why laboratories continually strive to improve the status of their TATs. A rapid TAT on some tests is essential for proper patient care.3 Fleisher and Schwartz state, “the more timely and rapidly testing is performed the more efficient and effective will be the treatment.”4

Laboratory personnel generally view the TAT as the time of receiving the specimen in the department to the time the testing is complete. But there are other aspects of the turnaround time that are often overlooked by the laboratory staff. According to Chernof, “On careful review, the seemingly simple process of laboratory ordering comprises many steps, including physician ordering, patient blood withdrawal by phlebotomist, nursing care, specimen transport, entry into the hospital information system, and so on. “5 To a clinician, TAT for a laboratory test extends from the time the order for a test is written until a result is reviewed.6

All laboratory tests can be divided into three phases: preanalytic, analytic, and postanalytic.7 It is usually the analytic phase with which the laboratory personnel are more concerned, but, to analyze and improve TATs, all three phases have to be examined because deficiencies can occur at any level. Valenstein defines the three phases as: preanalytic-the time required to requisition, collect, and transport specimens; analytic-the time required to prepare specimens and perform the analysis; and postanalytic-the time required to report results back to the patient’s physician.8

Regardless of how speedy the TAT is, will it ever be fast enough? More than 80% of clinical laboratories receive complaints about test TAT.9 Yet, there is little agreement among physicians about what constitutes acceptable TAT, which suggests that opinions of what a TAT ought to be are not based on objective analysis or uniform experiences.9 One study revealed that in 87% of institutions, clinicians complained about slow laboratory test TAT, mostly from the emergency room.” Most hospitals demonstrate disagreement in the definition of a TAT.”

The perception of what constitutes an appropriate TAT has changed over the years at the same pace as that of technological advances that decrease TATs. ATAT of four hours was accepted in the early 1980s for routine hematology and chemistry; however, this is no longer acceptable in the 1990s with care givers focusing on minimizing length of stay.12 Advancements in technologies, such as computers and pneumatic tubing systems, have allowed for vast improvements in the TAT. Therefore, the perception of what the TAT ought to be is continuing to change with each new innovation.

An increased TAT can cause dissatisfaction with the laboratory service and prolong the length of stay for patients in a hospital. One study found that an excessively long TAT for a laboratory test was a significant contributor to delayed disposition of patients in the emergency department. Another study showed that laboratory results that are not completed fast enough stimulate duplicate test requests, encourage stat testing, and delay patient hospital discharges which contribute to patient and physician dissatisfaction.1 Problems obtaining laboratory test results have been found to cause 9% of medically unnecessary hospital delays.8 Reducing therapeutic TAT has demonstrated a reduction in the cost of hospitalization.4 An insufficient TAT can directly affect patient care on many different levels.

With the increasing need to contain costs, the need for improvement of the TAT has to be weighed against the financial cost of this improvement to the institution. Handorf states: “Good quality, low cost, or fast turnaround time.. you can have any two. Goodquality and rapid results tended to be expensive; good-quality and low-cost results tended to be slower; low-cost and rapid results were generally available at a sacrifice of quality”13

Figure 1 shows the forced relationship between cost, quality, and speed, and the role of providers and their position when choosing between quality, cost, and speed of laboratory testing.’3 The cost of producing faster results can be as much as three times more expensive than producing a routine result.l Although the technology to improve a TAT might be good, it might also be too expensive for the institution when weighed against alternatives.

With the need to improve TATs in the laboratory, new concepts and technologies have been created. New ideas are aimed at getting the fastest possible TAT. Some of the proposed solutions for decreasing the TAT are: pneumatic tubing systems, point of care testing, satellite (stat) laboratories, computer technology, courier services, mobile/portable laboratory, and improved instrumentation, to name a few. With rapidly changing technology, `fast enough’ is continuing to get faster. The focus of this literature review is to examine the methods previously used for decreasing TATs. The overall goal is to provide a look at what has been done to improve the status of TATs. This examination of past efforts can establish a current position for decreasing the TAT and provide direction for further improvements.


Improvement of laboratory TATs has been shown to increase user satisfaction. Because of this, the laboratory needs to continue to provide the fastest TAT available within the means of the institution. With the new technologies introduced, there is a scattered perception of what will work and will not work. Using new technologies to improve the TAT can improve the patient care, improve user satisfaction, and decrease the hospital costs. There is not a current summary of all the methods available for the improvement of TATs in the laboratory. Besides creating a summary of the current literature available on TATs, this literature review can serve as a tool for laboratories to use in search for answers on how to improve TATs. LITERATURE SEARCH METHODOLOGY

In searching for information on TATs, MEDLINE, HealthSTAR, and CINAHL were the databases used. The keywords used were turnaround times, laboratories, and hospital laboratories. The articles were limited to those published in the English language. Articles from 1989 to the presentwere reviewed to keep the information current. CINAHL did not have any pertinent information on turnaround times. HealthSTAR and MEDLINE together produced 716 articles to be scanned. Of these articles, 50 contained information relevant to turnaround times and were reviewed more closely. Of the 50 that were reviewed, only 30 were included in this literature review


Any laboratory test can be divided into three phases: preanalytic, analytic, and postanalytic. Delays can occur at any of these phases. Measurement of TAT is a measure of efficiency and can highlight variations in processes so that these processes can be improved.’4 There are different perceptions of what constitutes a TAT for laboratory tests. The laboratory’s perception of a TAT is from the time the specimen is received until the time the test is resulted, not taking into consideration the time needed for ordering, collecting, and result reviewing. Physicians have a different perception. They perceive TAT as starting at the time that the order is written and ending when they review the result. Depending upon which party is measuring a TAT, the definition may change. But in order to truly serve users, the laboratory is going to have to move towards measuring the entire TAT, not just the time that the specimen is in the laboratory.


Studies have shown that the analytic phase is rarely the phase in which most delay occurs. Saxena and Wong concluded that a delay in review of the results by physicians was the greatest component of perceived TATs.6 They further conclude that the major causes of delays in the stat TATs were factors outside the control of the laboratory.6 Valenstein found that preanalytic delays were responsible for 90% to 96% of the total test TAT.? Green states that problems in availability of results were attributable to preanalytic components in the emergency department.11 Rollo and Fauser state that with modern instrumentation, analysis time comprises only 1% to 3% of the TAT.5 They further state that significant improvements in TAT can come only from improved specimen collection and transport to and handling within the laboratory.15 Regardless of the location of the delay, the criticism ultimately lies with the function of the laboratory and thus it is up to the laboratory to make or suggest the necessary improvements needed to correct the problem.

The majority of the literature has shown that most of the time the laboratory is not primarily the area of delay with respect to TAT. However, in performing analysis and reporting on surgical specimens, there is generally a long TAT.14 However, these tests and reports are usually performed and generated by the pathologist, not the technologist. Zarbo states that the TAT can be even more delayed when a resident is involved in the sign-out process.14 Another area where the TAT is affected by laboratory performance is in the processing of crossmatches by the blood bank.27 But given the critical nature of these tests, a longer TAT is generally tolerated. Hallam also states that the TAT can be longer on the weekend than during the daytime shift.27

Technology has allowed for the innovations necessary for the improvement of the TAT. Since a TAT has three phases, preanalytic, analytic, and postanalytic, these technologies have been designed for improvement at the particular phase of interest. In order to improve a TAT, the process has to be examined to highlight the phase where the problem exists. The deficient phase has to be targeted so the solution can be presented. In the literature, resolutions for improving the turnaround time were introduced and analyzed. Among the successful solutions presented in the literature were: pneumatic tubing system, satellite laboratory, point of care testing, and improved computer technology. These are the areas of technological advancements on which this literature review will be focused.

Pneumatic Tubing System

A pneumatic tubing system consists of stations throughout the hospital with a tube interconnecting them. Carriers can be placed in the tubes to carry samples to a desired destination. This method has proved successful in the reduction of the preanalytic phase of the TAT, which comprises the collection and delivery of the sample to the laboratory. This advancement can significantly reduce the time between collection and delivery of the sample to the laboratory for testing. One study found that inclusion of a pneumatic tubing system to expedite transport of specimens to the laboratory is a helpful tool in the reduction of TATs, with time range for specimen coming from different locations of 30 to 43 seconds.2 Other studies have also demonstrated an improved TAT with the installation of a pneumatic tubing system.4,16 Green demonstrated that the pneumatic tubing system not only improved the TAT, but it also resulted in a savings of 16 full-time messengers.” The ability to transport specimens to the laboratory rapidly makes the pneumatic tubing system an effective method of reducing the TAT. However, the pneumatic tube system is not perfect and like any piece of equipment, it has the tendency to break down. Samples can become misdirected and sample carriers can become trapped in the system causing a mild delay of the specimen delivery.2 Delays in transport can occur due to insufficient number of sample carriers and a system design based on transport of mail.6,18 One study demonstrated that the median transport times by pneumatic tubing system and other mechanical transport devices were not the fastest.17 However, some participants in this study had poorly designed tubing systems. Even though the pneumatic tubing system is not a perfect device, it has certainly proved to be successful in the reduction of a TAT. It is capable of delivering a specimen to the laboratory in a manner of seconds, as opposed to a longer delivery time by personnel. The pneumatic tubing system is an efficient method for hospitals to use in reduction of TAT without implementing a satellite stat laboratory.

Decentralized Testing

“Decentralized testing is defined by the Joint Commission on Accreditation of Healthcare Organizations as analytical testing performed at sites in the hospital but physically located outside of the hospital’s central laboratory.”19 Decentralized testing includes patient bedside testing (point-of-care testing) and testing in satellite laboratories. The current trend in laboratory medicine is to take testing to the patient instead of the patient, or patient’s specimen, coming to the laboratory. This trend towards decentralized testing is aimed at faster turnaround times and better patient care.20 A need for a rapid TAT is driving many hospitals to participate in decentralized testing, despite the fact that few hospitals could document cost savings and decrease in length of stay.19 With the changes in reimbursement from a fee for service system to a fixed rate of reimbursement, decentralized testing may not be economical.20 In a survey performed in 1994, 86% of the respondents said they actually performed decentralized testing.19 Despite the trend towards decentralized testing, it has been proven to be more costly than the centralized laboratory testing because of duplication of procedures and staffing.

Satellite Laboratory

Satellite laboratories exist outside of the central laboratory, usually in areas of the hospital where rapid patient care is essential. Setting up a satellite laboratory can help reduce the preanalytic portion of the TAT, but the postanalytic problems will still exist. Many of the services they offer are duplicate services also offered by the central laboratory. The duplication is required because of a need for a more rapid TAT. Johnson found that delays of surgery occurred more frequently in patients whose laboratory tests were processed in the central laboratory than in patients whose tests were processed in the onsite laboratory, and that this delay adds to hospital costs.21 Studies have concluded that the TAT in satellite laboratories was lower than that of the central laboratory.17

When considering a satellite laboratory, the cost has to be weighed against the need for faster results. Setting up a stat laboratory often involves the duplication of procedures already performed in the central laboratory at extra cost. The satellite laboratory also has to be staffed with separate personnel ready to operate the equipment when the stat result is desired.

Saxena and Wong found that a stat laboratory was not necessary to improve TAT because it only reduced the preanalytic phase of the TAT, and that resources could be better spent on other methods aimed at reduction of the preanalytic phase.6 Winkelman and Wybenga further concluded that a central laboratory with online computer system, pneumatic tubing system, and state of the art equipment could produce a result faster than a satellite laboratory.2 The satellite laboratory has had mixed reviews and further studies are needed to demonstrate effectiveness. Because of the expense involved with duplication and staffing, the implementation of a satellite laboratory should only be considered if no other alternative can be offered to provide better patient care and reduce the TAT.

Point-of-Care Testing

Point-of-care testing (POCT) involves the performance of a test at the point where the patient is located. POCT is by definition a bedside or near-bedside test.22 POCT is aimed at reducing TAT at every phase. The collection, analysis, and review of results are performed within minutes at the location of the patient. Lamb states that POCT can reduce TAT for certain laboratory tests and may reduce patients’ hospital stays.22 POCT is a technology that is becoming more and more popular. However, before World War II centralized laboratories were almost nonexistent and any testing was performed at or near the bedside of the patient.23 Technology has allowed laboratories to be more centralized, but there is a current trend (in the 1990’s) towards a return to bedside testing.23 Felder states that now more than 85% of 33 hospitals (from 19 states) which have more than 450 beds have fully staffed POCT laboratories.3 Tsai, Nash, Seamonds, and Weir state, “the ability to minimize TAT with use of a POCT device such as a portable clinical analyzer can result in quicker decisions regarding patient admission and discharge, earlier and more appropriate diagnosis, fewer tests, and shortened length of stay.”24 POCT can produce stat results within minutes, which can reduce the wait for the patient and physician.

However, as with every attempt at a more rapid TAT, POCT does not come without a cost. Tsai found that the cost per test of using a POCT analyzer rather than the central laboratory was significantly higher and that financial position could only improve with economies of scale.24 Therein, the cost of POCT has to be weighed against the need for faster results.

POCT has become the `front line’ of the laboratory in recent years. The number of hospitals performing POCT continues to grow. Because of growing popularity, there is a great need for a review and analysis of POCT.

Computer Technology

With the introduction of the laboratory to the computer age, the laboratory was able to more rapidly communicate results to the requesting department. Markin states, “the laboratory information system (LIS) is a fundamental building block in the development of a laboratory automation system (LAS).”20 Computers have the capability of reducing TAT at all phases. The order can go directly from the department to the laboratory. Instruments can be interfaced so that results go directly into the computer, which also reduces the risk of error. After results are reviewed by laboratory personnel, they are then readily available to the ordering physician to access via the computer. Computers have opened a new line of communication for the laboratory. Results are now available faster than before. DeMoranville and Ellis state that the introduction of automation into the laboratory will increase efficiency while improving TAT and maintaining or lowering labor costs.25 One study reports findings of substantially improved TATs, particularly for cross-site testing.12 Chou, Van Lente, and Castellani state, “computerized instrument interfaces, in which the user, the laboratory information system, and the instrument act as an integrated unit, can greatly improve productivity, user fatigue, and error rates.”26 Other studies have found that the computer system enabled the postanalytic review of results reduced from 41 minutes to an average of only 5 minutes.7 Hallam states that the use of a computer has reduced the TAT anywhere from 25% to 50%.27 Computers enable results to be available quicker and easier than the traditional `paper trail’.

There is very little conflicting information in the literature about the effects of computer technology on TATs. Most of the criticism had to do with physicians and nurses not wanting to use the computers. Hallam states that doctors and nurses don’t feel they should have to use the computer to find results, or else they don’t want to learn how.2 Therefore, it is easy to conclude that the integration of computers into laboratories had a profound impact on the improvement of TATs and the introduction of the laboratory to the computer age.


With the demand for quicker results, laboratories are continually searching for new methods in the improvement of TATs. By improving the TAT for laboratory tests, the laboratory can accomplish many things: 1) the physician will be more satisfied; 2) the patient will be more satisfied; 3) hospital administration will be happier if a lower TAT can decrease the length of stay (saving money); and 4) the staff’s attitude towards the laboratory will improve. The improved TAT is the key to user satisfaction for the laboratory.

All of the methods discussed in this literature review have had successes. These innovations for improving TAT worked, but not without a price. The key to finding the right tool for reducing TATs is to research the resources within the institution. The cost of the innovation has to be weighed against the need for a faster TAT for the patient and physician. Physicians want faster TATs. A laboratory usually has a limited set of resources, of which the physician has no knowledge.

Choosing the right innovation for an institution is a complicated process with many issues. Before trying to improve TATs at the request of anxious physicians, one must study the process currently being used so that the problem area can be targeted for improvement. Markin states that the combination of centralized (core) services and distributed specialized testing is likely the best solution for improving the TAT.zo Others state that laboratorians should monitor TAT, choose methods that improve TAT, and share their findings with physicians by publicizing TAT information.17

The literature has shown that the analytic phase of the TAT is not commonly the area in need of improvement, and the preanalytic and postanalytic phases are more frequently to blame for a delayed result. These phases most commonly occur outside of the function and control of the laboratory. With the constant demand of faster results by physicians, it is surprising to see that the review of the result by the physician is one of the more common delays in the TAT. Physicians should become more aware of and involved in the improvement process.

TATs have improved with the integration of the pneumatic tubing system, satellite laboratories, POCT, and computer technology. But which one is better and more cost efficient? The full effect of these innovations can only be understood by further research.

More recent technologies mentioned in the literature but not studied, include a mobile laboratory, conveyer system, multi-function analyzers, and robotics.28,29,30 The current understanding of these innovations in relation to TAT cannot be known until studies are conducted.

Although these innovations have provided improvements in TATs, laboratories are still plagued with the problem of prolonged TATs. Laboratories must continue to improve TATs. Often times, the delay of a TAT is the only observation that users have of the laboratory. Once the problem of a TAT has been identified, the process has to be adjusted to make up for the deficiency.

The laboratory is a complex organization within the hospital. But it has to function in conjunction with the hospital to give patients the best and fastest care possible. In the age of cost consciousness, hospitals cannot afford to lose customers because of poor satisfaction with service. The laboratory can be an important part of patient satisfaction by doing what is necessary, possible, and within their limits to improve the TAT of laboratory tests.


Howanitz PJ, Steindel SJ. Intralaboratory performance and laboratorians’ expectations for star turnaround times. Arch Pathol Lab Med 1991;115(10):977-83. Winkelman JW, Wybenga DR. Quantification of medical and operational factors determining central versus satellite laboratory testing of blood gases. Am J Clin Pathol 1944;102(1):7-10.

3. Felder R. Robotics and automated workstations for rapid response testing. AmJ Clin Pathol 1995;104(4): S26-S31.

4. Fleisher M, Schwartz MK. Automated approaches to rapid-response testing.

AmJ Clin Pathol 1995;104(4): S18-S25.

5. Chernof B, Hilborne L, Heckman M, and others. The link between the department of pathology and laboratory medicine and medical administration. Am J Clin Pathol 1995;103(4):S24-S29.

6. Saxena S, Wong ET. Does the emergency department need a dedicated stat laboratory? Am J Clin Pathol 1993; 100(6):606- 10. 7. Bluth EI, Lambert DJ, Lohmann TP, and others. Improvement in stat labora

tory turnaround time. Arch Intern Med 1992; 152:837-40. 8. Valenstein PN. Preanalytic delays as a component of test turnaround time. Lab Med 1990;21(7):448-51.

9. Valentstein P Can we satisfy clinicians’ demands for faster service? Should we try? Am J Clin Pathol 1989;92(5):705-6.

10. Howanitz PJ, Cembrowski GS, Steindel SJ, Long TA. Physician goals and laboratory test turnaround times. Arch Pathol Lab Med 1993;117:22-8. 11. Green M. Successful alternatives to alternate site testing. Arch Pathol Lab Med


12. Fattal GA, Tanasijevic MJ, Winkelman JW Evolution beyond the shared services model of consolidated hospital clinical laboratories. Arch Pathol Lab Med 1995;119(8):701-5.

13. Handorf CR. College of American pathologists conference XXVIII on alternate site testing: introduction. Arch Pathol Lab Med 1995;119(10):867-73.

14. Zarbo RJ, Gephardt GN, Howanitz PJ. Intralaboratory timeliness of surgical pathology reports. Arch Pathol Lab Med 1996;120(3):23444. 15. Rollo JL, Fauser BA. Computers in total quality management. Arch Pathol

Lab Med 1993,117(9):900-5.

16. McQueen MJ. Role of the laboratory in meeting the needs of critical care. Clin Biochem 1992;26(1):8-10.

17. Howanitz PJ, Steindel SJ, Cembrowski GS, Long TA. Emergency department stat test turnaround times. Arch Pathol Lab Med 1992; 116:122-8.

18. Allen KR, Harris CM. Measure of satisfaction of general practitioners with the chemical pathology services in Leeds Western Health District. Ann Clin Biochem 1992;29(Pt3):331-6.

19. Bickford GR. Decentralized testing in the 1990s. Clin Lab Med 1994; 14(3):623-45.

20. Markin RS. Clinical laboratory automation: concepts and designs. Semin Diagn

Pathol 1944;11(4):274-81.

21. Johnson KF. Does an on-site satellite laboratory reduce surgical delays? AORN J 1994;59(6):1279-82.

22. Lamb LS. Responsibilities in point-of-care testing. Arch Pathol Lab Med 1995;119(10):886-9.

23. McDonald JM, Smith JA. Value-added laboratory in an era of managed care.

Clin Chem 1995;41(8):1256-62.

24. Tsai WW, Nash DB, Seamonds B, Weir GJ. Point-of-care versus central laboratory testing: an economic analysis in an academic medical center. Clin Ther 1994;16(5):898-910.

25. DeMoranville VE, Ellis JE. Examples of enhanced laboratory workflow through the application of robotics. Clin Chem 1990;36(9):1588-90.

26. Chou D, Van Lente F, Castellani W Considerations in the design and implementation of user interfaces between laboratory instrumentation and laboratory information systems. Clin Chem 1990;36(9):1586-7. 27. Hallam K. Turnaround time: speeding up, but is it fast enough? Med Lab Observer 1988;20:28-34.

28. Fuhrman SA, Travers EM, Handorf CR. The mobile laboratory in alternative site testing. Arch Pathol Lab Med 1995;119(10):939-42.

29. Smellie WSA, Galloway PJ, Johnston JI. Laboratory turnaround time: closing the loop. J Clin Pathol 1995;48(4):372-5.

30. Brombacher PJ, Marell GJ, Westerhuis LWJJM. Laboratory work flow analysis and introduction of a multi-functional analyser. Eur J Clin Chem Clin Biochem 1996;34(3):287-92.

Pamela G Manor is a medical technologist at the University of Mississippi Medical Center Jackson MS.

Address for correspondence: Pamela G Manor, University of Mississippi Medical Center Department of Clinical Pathology, 2500 North State Street, Jackson, MS 39216 (601) 984-2373 or (601)984-2362.

Copyright American Society for Clinical Laboratory Science Mar/Apr 1999

Provided by ProQuest Information and Learning Company. All rights Reserved