Longer Turnaround Time Research Articles

Validation of Clinical Testing for Warfarin Sensitivity: Comparison of CYP2C9-VKORC1 Genotyping Assays and Warfarin-Dosing Algorithms

Responses to warfarin (Coumadin) anticoagulation therapy are affected by genetic variability in both the CYP2C9 and VKORC1 genes. Validation of pharmacogenetic testing for warfarin responses includes demonstration of analytical validity of testing platforms and of the clinical validity of testing. We compared four platforms for determining the relevant single nucleotide polymorphisms (SNPs) in both CYP2C9 and VKORC1 that are associated with warfarin sensitivity (Third Wave Invader Plus, ParagonDx/Cepheid Smart Cycler, Idaho Technology LightCycler, and AutoGenomics Infiniti). Each method was examined for accuracy, cost, and turnaround time. All genotyping methods demonstrated greater than 95% accuracy for identifying the relevant SNPs (CYP2C9 *2 and *3; VKORC1 -1639 or 1173). The ParagonDx and Idaho Technology assays had the shortest turnaround and hands-on times. The Third Wave assay was readily scalable to higher test volumes but had the longest hands-on time. The AutoGenomics assay interrogated the largest number of SNPs but had the longest turnaround time. Four published warfarin-dosing algorithms (Washington University, UCSF, Louisville, and Newcastle) were compared for accuracy for predicting warfarin dose in a retrospective analysis of a local patient population on long-term, stable warfarin therapy. The predicted doses from both the Washington University and UCSF algorithms demonstrated the best correlation with actual warfarin doses.

“Turnaround time”: a new parameter for the characterization of the overall efficacy of laboratory diagnostic processes

The authors developed a special computer-aided routine in their laboratory for the calculation of "turnaround time" which parameter is suitable for the characterization of the overall efficacy of laboratory diagnostic processes. The turnaround time is defined as the interval between the arrival time of a sample in the laboratory and the time of clinical validation. It characterizes the efficacy of the result generation process very well, and therefore, is considered as an important parameter of laboratory quality control. In their present study the authors analyzed the data of the urgent (stat), routine and special laboratory tests of 6 months and presented the median, 5- and 95-percentile values of turnaround time. Beside this, they calculated the rate of "outliers": the number of tests having a longer turnaround time value, than the defined maximal turnaround time (stat 1 hour, routine 4 hours, special 2-14 days). The median turnaround time values were 9-70 minutes for the stat tests and 33-190 minutes for the routine analytes. In case of special tests, the results were much more heterogeneous, in general non-automated hemostasis and immunochemistry assays, with low sample numbers had longer turnaround time values and higher number of outliers. Longitudinal analysis of routine tests showed clearly that turnaround time values became shorter in every unit during the 1st 6 months of 2006. Clinical validation is an important component altering turnaround time that can be shortened substantially with the installation of an autovalidation program. Based on the data of the authors the median turnaround time values of routine assays were shortened by 1-2 hours after introduction of autovalidation. The applied program for turnaround time analysis is suitable for evaluation of sample transfer times, too, that was presented by comparison of two "emergency units" having different sample transfer facilities. The described turnaround time analysis is part of the general routine processes in laboratories of the developed countries but is the first such trial in Hungary.

Nongynecologic cytology turnaround time: a College of American Pathologists Q-Probes study of 180 laboratories.

○ Objectives.-To determine the turnaround time for nongynecologic cytology and to identify laboratory and specimen characteristics associated with variations in turnaround time. Design and Setting.-Prospective evaluation of nongynecologic cytology turnaround times in 180 laboratories. Main Outcome Measure.-Nongynecologic cytology case turnaround time. Results.-Participants from 180 laboratories submitted turnaround times for 16950 nongynecologic cytology cases and submitted information describing their laboratories' practice characteristics relating to the processing of nongynecologic cytology specimens. Half of the participating laboratories had mean receipt to report turnaround times of 1.6 calendar days or less and were able to complete 90% of their cases within 3.0 calendar days. Ten percent of participants had mean turnaround times greater than 3.2 days and required 6.0 or more days to report 90% of their cases. Longer turnaround times were associated with processing fluid and fine-needle aspiration specimens, issuing atypical/suspicious for malignancy and nondiagnostic diagnoses, having cytotechnologist students screen slides, having to contact the physician offices for additional information, having to retrieve prior case material for review, and having to perform cell blocks and/or special stains. Conclusion.-There is an opportunity for laboratories to shorten nongynecologic turnaround time by altering certain laboratory practices.

Nongynecologic Cytology Turnaround Time

Abstract Objectives.—To determine the turnaround time for nongynecologic cytology and to identify laboratory and specimen characteristics associated with variations in turnaround time. Design and Setting.—Prospective evaluation of nongynecologic cytology turnaround times in 180 laboratories. Main Outcome Measure.—Nongynecologic cytology case turnaround time. Results.—Participants from 180 laboratories submitted turnaround times for 16 950 nongynecologic cytology cases and submitted information describing their laboratories' practice characteristics relating to the processing of nongynecologic cytology specimens. Half of the participating laboratories had mean receipt to report turnaround times of 1.6 calendar days or less and were able to complete 90% of their cases within 3.0 calendar days. Ten percent of participants had mean turnaround times greater than 3.2 days and required 6.0 or more days to report 90% of their cases. Longer turnaround times were associated with processing fluid and fine-needle aspiration specimens, issuing atypical/suspicious for malignancy and nondiagnostic diagnoses, having cytotechnologist students screen slides, having to contact the physician offices for additional information, having to retrieve prior case material for review, and having to perform cell blocks and/or special stains. Conclusion.—There is an opportunity for laboratories to shorten nongynecologic turnaround time by altering certain laboratory practices.

Gynecologic cytology turnaround time. A College of American Pathologists Q-Probes Study of 371 laboratories.

○ Objectives.-To determine the turnaround time for gynecologic cytology in a large sample of laboratories and to identify laboratory and specimen characteristics associated with better and worse performance. Design and Setting.-Prospective evaluation of gynecologic cytology turnaround times in 371 laboratories. Main Outcome Measure.-Gynecologic cytology case turnaround time. Results.-Three hundred seventy-one laboratories submitted information regarding laboratory characteristics and processes, and turnaround times of 66 042 gynecologic cytology cases. Half of the participating laboratories had mean turnaround times of 6 calendar days or less and were able to complete 90% of their cases within 8 calendar days. Ten percent of participants had mean turnaround times greater than 13 days and required 19 or more days to report 90% of their cases. Longer turnaround times were associated with the use of reference laboratories for all or part of the evaluation; contacting the physician's office for additional information; using cytotechnology students, residents, or fellows in the evaluation; and providing service on the weekend. Conclusion.-Practice patterns contribute to the long turnaround times for gynecologic cytology found in some laboratories and may be improved by local site-specific process analysis.

Gynecologic cytology turnaround time. A College of American Pathologists Q-Probes Study of 371 laboratories.

To determine the turnaround time for gynecologic cytology in a large sample of laboratories and to identify laboratory and specimen characteristics associated with better and worse performance. Prospective evaluation of gynecologic cytology turnaround times in 371 laboratories. Gynecologic cytology case turnaround time. Three hundred seventy-one laboratories submitted information regarding laboratory characteristics and processes, and turnaround times of 66 042 gynecologic cytology cases. Half of the participating laboratories had mean turnaround times of 6 calendar days or less and were able to complete 90% of their cases within 8 calendar days. Ten percent of participants had mean turnaround times greater than 13 days and required 19 or more days to report 90% of their cases. Longer turnaround times were associated with the use of reference laboratories for all or part of the evaluation; contacting the physician's office for additional information; using cytotechnology students, residents, or fellows in the evaluation; and providing service on the weekend. Practice patterns contribute to the long turnaround times for gynecologic cytology found in some laboratories and may be improved by local site-specific process analysis.

Urine Drug Screening

Illicit substance use among children and adolescents is a major health concern in our society. Increasingly, pediatricians are confronted by parents requesting that their children be tested for illicit drugs. Pediatricians and other practitioners, therefore, should be knowledgeable about drug testing techniques and understand how to interpret the results. Likewise, the legal and ethical issues surrounding drug testing should be evaluated thoroughly. The four urine drug screening tests used most commonly are: radioimmune assay (RIA), enzyme-multiplied immunoassay test (EMIT), fluorescent polarization immunoassay (FPIA), and latex agglutination test (ONTRAK). According to Schwartz, these newer, more sensitive immunoassay tests essentially have replaced the older, conventional thin-layer chromatography methodology, which required larger sample sizes and longer turn-around times.

Simulation of a semiconductor manufacturing line

Product turnaround time (TAT) is defined as the clock or elapsed time from wafer release to completed wafer fabrication. It is also known as cycle time, mean elapsed time, or manufacturing lead time. Turnaround time is arguably more important in semiconductor fabrication than in any other industry because it has a major impact on contamination levels, process control capabilities, yield-learning rates and product costs. Semiconductor manufacturers must strictly control particulate contamination to achieve high device yields. Longer turnaround times increase the opportunity for the particles to migrate to wafer surfaces, even in strict clean-room environments [11]. The negative relationship between time and product yields is shown in Figure 1. Submicron device fabrication also demands stringent process control capability. Variation in time between steps is a major contributor to process variability, directly affecting process yields. Sequential processes performed minutes apart may produce significantly different results than the identical processes performed hours apart because the properties of materials change over time. The slope of the yield learning curve is also a function of turnaround time. Slow feedback because of high turnaround times delays problem recognition and verification of solutions. Semiconductor fabrication is especially sensitive to turnaround time because definitive functional results are not available until circuits are completely fabricated on the wafe—typically hundreds of process steps after the raw silicon wafers are released into the manufacturing line. Figure 2 depicts the relationship between turnaround time, shown as a multiple of theoretical or raw process time (RPT), and the yield learning rate. The impact of longer turnaround time is not limited to reduced yields. Longer TAT also increases product costs. For example, a line with a 1O-day TAT that starts 1,000 wafers a day will have 10,000 wafers of work-in-process (WIP). A line with the same wafer starts per day (WSD) but an 11-day TAT will have 11,000 wafers in WIP. The longer TAT causes higher carrying costs for partially finished goods, more space for WIP storage, additional resources for product tracking and control, and many other additional expenses. Minimizing turnaround time is critically important in the semiconductor industry due to its major contribution to greater product yields and lower costs. However, it is not the only determinant of success in semiconductor manufacturing. State-of-the-art facilities cost hundreds of millions of dollars to build and equip, due to requirements for cleanliness, vibration control, chemical and gas purity and other components that are specified to angstroms and sub-microns. The semiconductor industry's capital-intensive nature demands high throughput rates and maximum utilization of resources to attain a competitive cost per wafer. The amount of work-in-process (WIP), also known as line-loading levels, affects both turnaround time and throughput performance. Throughput analysis techniques [4, 6] generate curves demonstrating that infinite levels of work in process maximize throughput (Figure 3) by ensuring that resources never starve for work. Queuing theory analysis [1] produces curves that show minimum line-loading levels produce minimum turnaround times by eliminating time spent queued for busy resources (Figure 4). The inverse shapes of these two performance curves demonstrate the inherent conflict in line-loading decisions when attempting to both maximize throughput and minimize turnaround time. Wafer fabrication involves hundreds of individual tools performing multiple processes to produce an array of sophisticated end products. Actual turnaround time and throughput curves for each tool depend on many variables unique to that tool, such as arrival rates, service rates, rework rates, failure rates, and starvation and blockage opportunities. Resolution of the line-loading conflict is especially difficult given the complexity of semiconductor manufacturing, and simulation emerges as perhaps the only currently existing methodology for taking into account the detailed interactions among elements in such a manufacturing environment [3, 14].

Assessment of Four Enzyme Immunoassay Kits for Serum β‐hcg Screening

This pilot study evaluates four qualitative serum beta-human chorionic gonadotropin (beta-hCG) enzyme immunoassay kits for both routine pregnancy testing and screening for ectopic pregnancy. We found that the Tandem-E HCG assay had the lowest limit of detection, and longest turnaround time. Tandem ICON HCG assay had the shortest turnaround time. The Vis-Con II was the most economical batch test. The Quest assay kit was both fast and simple and had the lowest cost for stat testing.