An inter-laboratory survey of paediatric bilirubin analyses.

A regional quality control trial of paediatric bilirubin analyses is described. The overall performance of the group was unsatisfactory with an unacceptably high inter-laboratory variation. The use of a common standard produced improvement in performance but it is concluded that the poor performance was also due to methodological problems. This lack of agreement between laboratories is a major problem when patients are transferred between hospitals.     

Q-tracks: a College of American Pathologists program of continuous laboratory monitoring and longitudinal tracking

CONTEXT: Continuous monitoring of key laboratory indicators of quality by hundreds of laboratories in a standardized measurement program affords an opportunity to document the influence of longitudinal tracking on performance improvement by participants focused on that outcome. OBJECTIVE: To describe the results of the first 2 years of participation in a unique continuous performance assessment program for pathology and laboratory medicine. DESIGN: Participants in any of 6 modules in the 1999 and 2000 College of American Pathologists (CAP) Q-Tracks program collected data according to defined methods and sampling intervals on standardized input forms. Data were submitted quarterly to CAP for statistical analysis. Interinstitutional comparison reports returned in 6 weeks provided each laboratory with its performance profile of key indicators and its percentile ranking compared with all participants in that quarter. This also included longitudinal comparisons of performance during previous cumulative quarters. Control charts graphically displayed data with flags identifying performance points that were out of statistical control. SETTING: Hospital-based laboratories in the United States (98%), Canada, and Australia. PARTICIPANTS: Voluntary subscriber laboratories in the CAP Q-Tracks performance measurement program: roughly 70% from hospitals of 300 occupied beds or fewer, 65% from private, nonprofit institutions, slightly more than half located in cities, one third from teaching hospitals, and 20% with pathology residency training programs. MAIN OUTCOME MEASURES: Each module measured several major and additional minor quality indicators and unbenchmarked individualized data for internal use. RESULTS: Participants in 4 of 6 Q-Tracks continuous monitors demonstrated statistically significant performance improvement trends in 1999 and 2000, which were most marked for laboratories that continued participation throughout both years. These monitors were wristband patient identification, laboratory specimen acceptability, blood product wastage, and intraoperative frozen section consultation. CONCLUSIONS: Key continuous indicators chosen on the basis of a decade's experience in the CAP Q-Probes quality improvement program are useful measurement and benchmarking tools for laboratories to improve performance. In general, measures in which there is a broad range of demonstrable performance initially are most optimal for subsequent improvement using continuous monitoring. These studies have shown that quality is not static, but rather is a moving benchmark of performance as seen in the redefinition of benchmarks over time by participants in the first 2 years of the CAP Q-Tracks program.     

Mechanisms to assess Gram stain interpretation proficiency of technologists at satellite laboratories

To address Gram stain interpretation proficiency in a satellite/centralized microbiology laboratory paradigm, two programs were devised. In quality assurance program 1, nonmicrobiology technologists at satellite laboratories were required to interpret standardized Gram-stained specimens of clinical material prepared by an experienced microbiologist at a central laboratory. In quality assurance program 2, clinical Gram stains prepared and read by the satellite laboratorians were reviewed by experienced microbiologists at the central laboratory. Satisfactory performance (94%) was achieved in quality assurance program 1. In contrast, quality assurance program 2 had a significantly lower overall performance (89%; P < 0.0001) due to poorer identification of host cells (93%) and bacteria (84%). A variety of intervention mechanisms, including continuous monitoring, resulted in overall performance improvement (P < or = 0.006). While a technologist challenge has educational merit, having a microbiologist review previously read slides is a better indicator of the technologist's Gram stain interpretation proficiency.     

Observer variation and quality control of cytodiagnosis

The aim of quality control of a laboratory investigation is to ensure that similar results are obtained on the same material at different centres. To investigate its practicability in cytodiagnosis, the same cytological material was examined independently at six centres. Each centre supplied material from 20 cases, providing a total of 120 cases, ie, 100 cases excluding the donor centre's own material. The degree of agreement between the centres was studied using (a) the standard National Health Service cytology report terminology, (b) the centre's own terminology, and (c) the recommended recall time. The results revealed close agreement between five out of six centres in the reports obtained in relation to dysplasia and malignancy, namely, less than 3% false negative results and not more than 1.7% false positive results. The recommended recall time provided a similar order of agreement after discrepancies due to the management of inflammatory conditions had been eliminated. There was marked disagreement in the diagnosis of both presence and type of infection. The results indicate that improvement in the quality of cytological material would increase the consistency of cytodiagnosis. Cytodiagnosis itself, being an expression of opinion, does not appear to be an appropriate field for quality control.     

Basecalling with LifeTrace

A pivotal step in electrophoresis sequencing is the conversion of the raw, continuous chromatogram data into the actual sequence of discrete nucleotides, a process referred to as basecalling. We describe a novel algorithm for basecalling implemented in the program LifeTrace. Like Phred, currently the most widely used basecalling software program, LifeTrace takes processed trace data as input. It was designed to be tolerant to variable peak spacing by means of an improved peak-detection algorithm that emphasizes local chromatogram information over global properties. LifeTrace is shown to generate high-quality basecalls and reliable quality scores. It proved particularly effective when applied to MegaBACE capillary sequencing machines. In a benchmark test of 8372 dye-primer MegaBACE chromatograms, LifeTrace generated 17% fewer substitution errors, 16% fewer insertion/deletion errors, and 2.4% more aligned bases to the finished sequence than did Phred. For two sets totaling 6624 dye-terminator chromatograms, the performance improvement was 15% fewer substitution errors, 10% fewer insertion/deletion errors, and 2.1% more aligned bases. The processing time required by LifeTrace is comparable to that of Phred. The predicted quality scores were in line with observed quality scores, permitting direct use for quality clipping and in silico single nucleotide polymorphism (SNP) detection. Furthermore, we introduce a new type of quality score associated with every basecall: the gap-quality. It estimates the probability of a deletion error between the current and the following basecall. This additional quality score improves detection of single basepair deletions when used for locating potential basecalling errors during the alignment. We also describe a new protocol for benchmarking that we believe better discerns basecaller performance differences than methods previously published.     

Accuracy of reporting endocervical component adequacy--a continuous quality improvement project

Inaccurate reporting of the absence of an endocervical (EC) component on Pap smears often results in slide rescreens, amended reports, clinician dissatisfaction, and sometimes unnecessary repeat smears. Therefore, the accuracy of reporting EC component adequacy was selected as a quality indicator for the laboratory continuous quality improvement program (CQI). The process consisted of problem identification, analysis of the situation, collection of data, implementation of solutions, and evaluation of results. The objective of the study was to determine if the accuracy of reporting EC component adequacy on Pap smears improved after application of such a program. During the first phase, 150 Pap smears originally reported with the absence of an adequate EC component and 150 smears reported with the presence of an adequate EC component were rescreened to measure the baseline accuracy of EC component adequacy reporting. The improvement process was then implemented. A cause-and-effect diagram was developed and root cause was determined. A presentation was then made to the cytology staff. Criteria for EC component adequacy were reviewed, examples were shown, and standardized marking of EC component was implemented. Following improvement actions, a second audit of 150 Pap smears reported with the absence of an adequate EC component as well as 150 smears reported with the presence of an adequate EC component was undertaken to measure change in performance in assessing EC component adequacy. For the baseline rescreening, before initiation of the CQI program, 98% accuracy was achieved with smears that were reported as adequate for EC component present. However, the accuracy with smears reported as absence of an adequate EC component was only 71%, i.e., an adequate EC component was identified in almost 1/3 of these cases on rescreen. After the implementation of improvement actions, the accuracy with smears reported with the presence of EC component remained high (98%) and the accuracy of reporting the absence of EC component was 90%. The difference of the latter before and after the implementation was statistically significant (P = 0.015, z-test). The accuracy of reporting EC component adequacy increased following the CQI process. Using reporting EC component adequacy as an example, we demonstrate that by treating clinical problems as quality control issues and applying basic quality improvement tools, a positive outcome can be effected.     

An institutional system to monitor and improve the quality of residency education.

PURPOSE: This study sought to investigate whether an institution's Graduate Medical Education Committee (GMEC) could develop a system of continuous quality improvement of its residency programs using an annual survey provided by the institution for all residents. METHOD: Beginning in 2000, residents were surveyed annually about their educational and work environments. The GMEC determined standards of performance for the items on the survey based on four areas commonly cited by the Accreditation Council for Graduate Medical Education: supervision, feedback/evaluation, scholarly time, and duty hours. Residency program directors submitted action plans to improve those areas rated below the standard by the residents in the program. RESULTS: The 2000 survey served as baseline. In 2001, residency programs met the standard for 55.2% of the items, and 18 programs submitted 67 action plans. In 2002, programs met the standard for 80.6% of the items. For the items below standard, programs showed improvement in 14.9% and declined in 4.5% of the items compared with baseline. Six of the 18 programs had accreditation site visits during the study period. Five received no citations in the targeted areas. The sixth program was visited three months after it developed action plans for its six deficient areas. It received citations for two of the six areas. CONCLUSION: An institution that sponsors residency programs can develop and sustain an effective system to continuously monitor and evaluate its programs and improve the educational quality as evidenced by successful accreditation decisions.     

Investigation of the Variability in the Assessment of Digital Chest X-ray Image Quality

A large database of digital chest radiographs was developed over a 14-month period. Ten radiographic technologists and five radiologists independently evaluated a stratified subset of images from the database for quality deficiencies and decided whether each image should be rejected. The evaluation results showed that the radiographic technologists and radiologists agreed only moderately in their assessments. When compared against each other, radiologist and technologist reader groups were found to have even less agreement than the inter-reader agreement within each group. Radiologists were found to be more accepting of limited-quality studies than technologists. Evidence from the study suggests that the technologists weighted their reject decisions more heavily on objective technical attributes, while the radiologists weighted their decisions more heavily on diagnostic interpretability relative to the image indication. A suite of reject-detection algorithms was independently run on the images in the database. The algorithms detected 4 % of postero-anterior chest exams that were accepted by the technologist who originally captured the image but which would have been rejected by the technologist peer group. When algorithm results were made available to the technologists during the study, there was no improvement in inter-reader agreement in deciding whether to reject an image. The algorithm results do, however, provide new quality information that could be captured within a site-wide, reject-tracking database and leveraged as part of a site-wide QA program.     

How did it work? Who did it work for? Mediation in the context of a moderated prevention effect for children of divorce

This study presents a reanalysis of data from an effective preventive intervention for children from divorced families to test mediation of program effects. The study involved 157 children, age 9-12 years, who were randomly assigned to a parenting program or a literature control condition. Program effects to reduce posttest internalizing problems were mediated through improvement in mother-child relationship quality. Program effects to reduce externalizing problems at posttest and 6 months were mediated through improvement in posttest parental methods of discipline and mother-child relationship quality. The study also describes a new methodology to test mediation of Program x Baseline Status interactions. Analyses demonstrate mediation effects primarily for children who began the program with poorer scores on discipline, mother-child relationship quality, and externalizing problems.     

A relationship between perceived self-efficacy and quality of life in cancer patients

The quality of life of cancer patients may be influenced by the degree of control they feel able to exert over stressful situations arising from having the disease. We were able to test this association using a newly developed instrument, the Stanford Inventory of Cancer Patient Adjustment which assesses perceived self-efficacy, that is, perceived ability to enact coping strategies. In a heterogeneous sample of 273 cancer patients a strong positive correlation was found between self-efficacy and quality of life and between self-efficacy and mood. Improvements in all three measures brought about by a brief, group program teaching coping skills were also highly correlated. By contrast, no significant association was seen between improvement in mood or quality of life and amount of home practice of coping skills.     

Assessing Safety Attitudes among Healthcare Providers after a Hospital-Wide High-Risk Patient Care Program

Purpose

Cardiopulmonary resuscitation (CPR) is commonly performed in high-risk, high intensity situations and is therefore a good procedure around which to develop and implement safety culture strategies in the hospital. The purpose of this study was to evaluate the impact of a hospital-wide quality improvement program on the management of sudden cardiac arrests by assessing healthcare providers'' attitudes towards patient safety.

Materials and Methods

This study was designed as a prospective cohort study at a single academic medical center. The comprehensive hospital-based safety program included steps to identify areas of hazard, partner units with the Resuscitation Committee, and to conduct a Safety Attitudes Questionnaire (SAQ). The SAQ evaluated 35 questions in seven domains to assess changes in patient safety culture by comparing the results before and after the hospital-wide high risk patient care improvement program.

Results

The response rates of the pre- and post-SAQ survey were 489 out of 1121 (43.6%) and 575 out of 1270 (45.3%), respectively. SAQ survey responses revealed significant improvement in all seven domains of the questionnaire (p-values of 0.006 and lower). In a subgroup analysis, doctors and nurses showed improvement in five domains. Both doctors and nurses did not show improvement in the "sharing information" domain.

Conclusion

A hospital-wide quality improvement program for high-risk, high reliability patient care involving CPR care was shown to be associated with a change in healthcare providers'' attitudes towards patient safety. Through an immersive and active program on CPR care, change in healthcare providers'' attitudes towards patient safety was initiated.     

Continuous wristband monitoring over 2 years decreases identification errors: a College of American Pathologists Q-Tracks Study

CONTEXT: Identification of patients is one of the first steps in ensuring the accuracy of laboratory results. In the United States, hospitalized patients wear wristbands to aid in their identification, but wristbands errors are frequently found. OBJECTIVE: To investigate if continuous monitoring of wristband errors by participants of the College of American Pathologists (CAP) Q-Tracks program results in lower wristband error rates. SETTING: A total of 217 institutions voluntarily participating in the CAP Q-Tracks interlaboratory quality improvement program in 1999 and 2000. DESIGN: Participants completed a demographic form, answered a questionnaire, collected wristband data, and at the end of the year, best and most improved performers answered another questionnaire seeking suggestions for improvement. Each institution's phlebotomists inspected wristbands for errors before performing phlebotomy and recorded the number of patients with wristband errors. On a monthly basis, participants submitted data to the CAP for data processing, and at the end of each quarter, participants received summarized comparisons. At the end of each year, participants also received a critique of the results along with suggestions for improvement. MAIN OUTCOME MEASURES: The percentage of wristband errors by quarter, types of wristband errors, and suggestions for improvement. RESULTS: During 2 years, 1 757 730 wristbands were examined, and 45 197 wristband errors were found. The participants' mean wristband error rate for the first quarter in 1999 was 7.40%; by the eighth quarter, the mean wristband error rate had fallen to 3.05% (P <.001). Continuous improvement occurred in each quarter for participants in the 1999 and 2000 program and in 7 of 8 quarters for those who participated in both 1999 and 2000. Missing wristbands accounted for 71.6% of wristband errors, and best performers usually had wristband error rates under 1.0%. The suggestion for improvement provided by the largest number of best and most improved performers was that phlebotomists should refuse to perform phlebotomy on a patient when a wristband error is detected. CONCLUSIONS: The wristband error rate decreased markedly when this rate was monitored continuously using the CAP Q-Tracks program. The Q-Tracks program provides a useful tool for improving the quality of services in anatomic pathology and laboratory medicine.     

Evolution of an international external quality assurance model to support laboratory investigation of Streptococcus pneumoniae, developed for the SIREVA project in Latin America, from 1993 to 2005

In 1993 the Pan American Health Organization initiated a laboratory-based surveillance system, called the SIREVA project, to learn about Streptococcus pneumoniae invasive disease in Latin American children. In 1994, National Laboratories in six countries were trained to perform serotyping and antibiotic susceptibility testing using broth microdilution to determine the MIC for specified antibiotics. An international External Quality Assurance (EQA) program was developed to monitor and support ongoing laboratory performance. The EQA program was coordinated by the National Centre for Streptococcus (NCS), Edmonton, Canada, and included external proficiency testing (EPT) and a validation process requiring regular submission of a sample of isolates from each laboratory to the NCS for verification of the serotype and MIC. In 1999, the EQA program was decentralized to use three of the original laboratories as regional quality control centers to address operational concerns and to accommodate the growth of the laboratory network to more than 20 countries including the Caribbean region. The overall EPT serotyping accuracies for phase I (1993 to 1998) and phase II (1999 to 2005) were 88.0 and 93.8%, respectively; the MIC correlations within +/-1 log(2) dilution of the expected result were 83.0 and 91.0% and the interpretive category agreements were 89.1 and 95.3%. Overall, the validation process serotyping accuracies for phases I and II were 81.9 and 88.1%, respectively, 80.4 and 90.5% for MIC agreement, and 85.8 and 94.3% for category agreement. These results indicate a high level of testing accuracy in participating National Laboratories and a sustained increase in EQA participation in Latin America and the Caribbean.     

Quality care improvement program in a community-based participatory research project: example of Project DIRECT

A continuous quality care improvement program (CQIP) was built into Project DIRECT (Diabetes Interventions Reaching and Educating Communities Together) to improve providers' patterns of diabetes care and patients' glycemic control. Project DIRECT consisted of a comprehensive program aimed at reducing the burden of diabetes in the vulnerable high-risk African-American population of southeast Raleigh, NC. Forty-seven providers caring for this target population of adult diabetes patients were included in this quasi-experimental study. At the initial session, providers learned about the CQIP components, completed a planning worksheet, and chose a CQIP coordinator. Educational events included continuing education in practices and through conferences by experts, and guideline distribution. Follow-up was accomplished through phone calls and visits. Effectiveness was measured by a change in prevalence of selected patterns of care abstracted from 1,006 medical charts. Appropriate statistical methods were used to account for the cluster design and repeated measures. At the fourth follow-up year, approximately 40% of providers still participated in the program. Among the providers who stayed in the program for the whole study period, most selected quality care patterns showed significant upward trends. Glycemic control indicators did not change, however, despite an increased number of hemoglobin A1c tests per year. A diabetes CQI program can be effectively implemented in a community setting. Improved performance measures were not associated with improved outcomes. These results suggest that a patient-centered component should reinforce the provider-centered component.     

Accuracy of gleason grading by practicing pathologists and the impact of education on improving agreement

The aims of this study were to evaluate the accuracy of Gleason grading for prostatic adenocarcinoma among practicing pathologists in Japan and to determine the influence of education on this accuracy. Using a case-oriented approach, 16 hematoxylin and eosin-;stained glass slides with consensus scores established by 4 urologic pathologists were reviewed by 91 pathologists, divided into 2 groups. In group A, average agreements with consensus scores before and after an educational lecture were 55.7% (n = 17) and 68.4% (n = 25), and average kappa values were 0.43 and 0.67, respectively. Twelve pathologists reviewed slides twice in a different order, with average agreements of 59.5% and 77.6%, and average kappa values of 0.48 and 0.69 before and after the lecture, yielding a statistically significant improvement. In group B, the average agreement before providing an atlas with a tutorial was 61.3% (n = 61), and the kappa value was 0.44. In the second round, the average agreement was 74.5% (n = 39), and the kappa value was 0.68. Among 39 pathologists who reviewed slides twice, the average agreement in the first round was 58.8%, and the kappa value was 0.42. Improvement of both the average agreement and the kappa value were statistically significant. The average improvement in kappa values among participants who reviewed slides twice was 0.22 in group A and 0.27 in group B, a difference that is not statistically significant. Combining both groups, the incidence of concordant scores for 16 cases rose from 58.9% to 75.4%, an average increase of 16.5%. The undergrading of score 5-7 lesions was significantly reduced, from 36.3% to 14.2%. With respect to demographic factors, pathologists signing out more than 5000 cases per year showed a better agreement than those with more than 1000 cases per year (48.9% versus 78.8%; P = 0.031). These results indicate that the general agreement of Gleason scores among practicing pathologists in Japan was comparable with those in the Western countries as reported in the literature. Although this requires further improvement, both the lecture and the printed material had a similar influence on the degree of improvement.     

Review of scheduled performance assurance inspections

The frequency of inspection of the authors' scheduled maintenance program was reviewed and modified, using the work of Fennigkoh (1989). This work extended to 2,700 devices located at four hospital sites supported by a regional service. These devices included all clinical equipment, including diagnostic imaging and renal dialysis. Review of the inspection frequencies was necessary as part of the quality assurance program and to ensure consistency between similar devices. Equipment was first evaluated according to four criteria to determine if it should be on the scheduled performance assurance program. These criteria included: equipment function, physical risk to patients, maintenance requirements, and incident or related history. The frequency of inspection of included devices was then assessed according to an algorithm that looked at device maintenance requirements and manufacturers' recommendations. Devices were scheduled for inspection once, twice or, in rare cases, four times per year. The quality of the inspection program was enhanced by a systematic review. As an added bonus, the required staffing resources to comply with the scheduled performance assurance declined by 29%.     

Achieving the Health Care Financing Administration limits by quality improvement and quality control. A real-world example.

With the enactment of the Clinical Laboratory Improvement Amendments of 1988 (CLIA 88), the federal government is now using proficiency testing as the primary indicator of laboratory quality. Laboratories with proficiency test failures are now at risk of a variety of harsh penalties including large monetary fines and suspension of operations. To minimize the risk of failed proficiency testing, we initiated a continuous quality improvement program in our general chemistry laboratory in conjunction with the use of a new survey-validated quality control product. This article describes the quality improvement program and our success in reducing the long-term random error in general chemistry. Despite our improvement program, significant analytical errors (greater than 30% of the CLIA limits) still exist in analytes measured by our chemistry analyzer. These errors are present in nearly the same analytes measured by other common chemistry analyzers indicating the need for improvement in their design and manufacture.     

The stability of liquid-filled matrix ionization chamber electronic portal imaging devices for dosimetry purposes

This study was performed to determine the stability of liquid-filled matrix ionization chamber (LiFi-type) electronic portal imaging devices (EPID) for dosimetric purposes. The short- and long-term stability of the response was investigated, as well as the importance of factors influencing the response (e.g., temperature fluctuations, radiation damage, and the performance of the electronic hardware). It was shown that testing the performance of the electronic hardware as well as the short-term stability of the imagers may reveal the cause of a poor long-term stability of the imager response. In addition, the short-term stability was measured to verify the validity of the fitted dose-response curve immediately after beam startup. The long-term stability of these imagers could be considerably improved by correcting for room temperature fluctuations and gradual changes in response due to radiation damage. As a result, the reproducibility was better than 1% (1 SD) over a period of two years. The results of this study were used to formulate recommendations for a quality control program for portal dosimetry. The effect of such a program was assessed by comparing the results of portal dosimetry and in vivo dosimetry using diodes during the treatment of 31 prostate patients. The improvement of the results for portal dosimetry was consistent with the deviations observed with the reproducibility tests in that particular period. After a correction for the variation in response of the imager, the average difference between the measured and prescribed dose during the treatment of prostate patients was -0.7%+/-1.5% (1 SD), and -0.6%+/-1.1% (1 SD) for EPID and diode in vivo dosimetry, respectively. It can be concluded that a high stability of the response can be achieved for this type of EPID by applying a rigorous quality control program.     

Evaluation of a faculty development program in managing care.

PURPOSE. To evaluate a faculty development program that teaches quality improvement and cost-effectiveness. METHOD. From October 2000 to February 2001, a two-part faculty development program was offered to 39 physicians from 19 U.S. medical schools supported by grants from the Partnerships for Quality Education (PQE) and Undergraduate Medical Education in the 21st Century (UME-21). Special features of the program included partnerships between academic and community physicians from each school, development of an educational innovation of interest to the participants, concurrent development of teaching skills and new medical knowledge, learning leadership skills (e.g., how to train colleagues to teach), and practice periods. The program focused on quality improvement and cost-effectiveness, but included other "managing care" topics. Prior to and after the course, participants assessed their knowledge of and competence to teach these topics, as well as other managing care topics. They also assessed their competence as medical educators and leaders. After the course, they indicated their progress in implementing their proposed educational innovations. RESULTS. Thirty-two of the 39 physicians completed evaluations both before and after the program. Self-assessed knowledge and competence to teach quality improvement and cost-effectiveness were significantly higher at the end of the course, as were all self-assessed teaching and leadership skills. The largest change scores occurred in assessments of competency to teach the new topics and to teach in new ways. Participants who implemented their innovations rated their competencies to teach quality improvement and cost-effectiveness higher than did non-implementers. CONCLUSION. Opportunities for faculty to learn how to teach a topic of stated importance to them, to practice what they have learned, and to work collaboratively with partners improved teaching skills.     

Comparison of results of voriconazole disk diffusion testing for Candida species with results from a central reference laboratory in the ARTEMIS global antifungal surveillance program

The accuracy of antifungal susceptibility testing is important for reliable resistance surveillance and for the clinical management of patients with serious infections. Our primary objective was to compare the results of voriconazole disk diffusion testing of Candida spp. performed by centers participating in the ARTEMIS program with disk diffusion and MIC results obtained by the central reference laboratory. A total of 2,934 isolates of Candida spp. were tested by CLSI disk diffusion and reference broth microdilution methods in the central reference laboratory. These results were compared to the results of disk diffusion testing performed in the 54 participating centers. All tests were performed and interpreted following CLSI recommendations, as follows: susceptible (S), MIC of or=17 mm); susceptible dose dependent (SDD), MIC of 2 microg/ml (14 to 16 mm); and resistant (R), MIC of >or=4 microg/ml (or=4 microg/ml) by MIC testing. External quality assurance data obtained by surveillance programs such as the ARTEMIS Global Antifungal Surveillance Program ensure the generation of useful surveillance data and result in the continued improvement of antifungal susceptibility testing practices.