Peter J. Howanitz

CONTEXT: Patient safety is influenced by the frequency and seriousness of errors that occur in the health care system. Error rates in laboratory practices are collected routinely for a variety of performance measures in all clinical pathology laboratories in the United States, but a list of critical performance measures has not yet been recommended. The most extensive databases describing error rates in pathology were developed and are maintained by the College of American Pathologists (CAP). These databases include the CAP's Q-Probes and Q-Tracks programs, which provide information on error rates from more than 130 interlaboratory studies. OBJECTIVES: To define critical performance measures in laboratory medicine, describe error rates of these measures, and provide suggestions to decrease these errors, thereby ultimately improving patient safety. SETTING: A review of experiences from Q-Probes and Q-Tracks studies supplemented with other studies cited in the literature. DESIGN: Q-Probes studies are carried out as time-limited studies lasting 1 to 4 months and have been conducted since 1989. In contrast, Q-Tracks investigations are ongoing studies performed on a yearly basis and have been conducted only since 1998. Participants from institutions throughout the world simultaneously conducted these studies according to specified scientific designs. The CAP has collected and summarized data for participants about these performance measures, including the significance of errors, the magnitude of error rates, tactics for error reduction, and willingness to implement each of these performance measures. MAIN OUTCOME MEASURES: A list of recommended performance measures, the frequency of errors when these performance measures were studied, and suggestions to improve patient safety by reducing these errors. RESULTS: Error rates for preanalytic and postanalytic performance measures were higher than for analytic measures. Eight performance measures were identified, including customer satisfaction, test turnaround times, patient identification, specimen acceptability, proficiency testing, critical value reporting, blood product wastage, and blood culture contamination. Error rate benchmarks for these performance measures were cited and recommendations for improving patient safety presented. CONCLUSIONS: Not only has each of the 8 performance measures proven practical, useful, and important for patient care, taken together, they also fulfill regulatory requirements. All laboratories should consider implementing these performance measures and standardizing their own scientific designs, data analysis, and error reduction strategies according to findings from these published studies.

CONTEXT: Critical values lists have been used for many years to decide when to notify physicians and other caregivers of potentially life-threatening situations; however, these lists have not been studied widely. OBJECTIVES: To investigate critical values lists in institutions participating in the College of American Pathologists Q-Probes program and to provide suggestions for improvement. SETTING: A total of 623 institutions voluntarily participating in the Q-Probes program. DESIGN: A multipart study in which participants responded to information from preprinted lists, collected information about current practices, completed a questionnaire, monitored critical values calls, reviewed patients' medical records, and surveyed nursing supervisors and physicians about critical values. MAIN OUTCOME MEASURES: Defining critical values systems, including lists, personnel, costs, processes, usefulness, and related medical outcomes. RESULTS: Critical values lists were determined for routine chemistry and hematology analytes and were found to vary widely among participants. In contrast, more than 95% of participants reported positive blood cultures, cerebrospinal fluid cultures, and toxic therapeutic drug levels as critical values. Based on more than 13 000 critical values, participants' data showed that most critical values reports (92.8%) were made by the person who performed the test, and that 65% of reports for inpatients were received by nurses. For outpatients, physicians' office staff received the largest percentage (40%) of reports. The majority of participants (71.4%) had no policy on how repeat critical calls should be handled. On average, completion of notification required about 6 minutes for inpatients and 14 minutes for outpatients. Slightly greater than 5% of critical value telephone calls were abandoned, with the largest percentage abandoned for outpatients. More than 45% of critical values were unexpected, and 65% resulted in a change in therapy. Although only 20.8% of 2301 nursing supervisors thought critical values lists were helpful, 94.9% of 514 physicians found critical values lists valuable. CONCLUSIONS: Critical values systems were medically important, highly variable, but also costly practices for participants. We propose a number of recommendations for improvement, including that the critical values list should be approved by the medical staff, each laboratory should develop a written policy for handling initial and repeat critical values reports, a foolproof policy should be established to report results from calls abandoned, and efforts at automating the process should become widespread.

OBJECTIVE: To examine clinical and laboratory practices associated with contamination of blood culture specimens from adults. DESIGN AND SETTING: A College of American Pathologists Q-Probes quality improvement study involving prospective evaluation of adult blood culture contamination rates in 640 institutions. MAIN OUTCOME MEASURE: Proportion of contaminated blood cultures. RESULTS: A total of 497134 blood cultures were studied. The median adult inpatient blood culture contamination rate was 2.5% (central 80th percentile=0.9%-5.4%) by laboratory assessment. There was no significant difference in contamination rates between inpatient and outpatient cultures (P=.273). The median contamination rate by clinical assessment (2.1%) was significantly lower (P=.005), primarily because of a lower proportion of cultures with coagulase-negative Staphylococcus that were interpreted as contaminants when only one of multiple specimens was positive. Specimen collection variables associated with significantly lower contamination rates included use of a dedicated phlebotomy service (P=.039), use of tincture of iodine for skin disinfection (P=.036), and application of an antiseptic to the top of the collection device before inoculation (P=.018). Teaching institutions and high numbers of occupied beds were demographic factors associated with higher contamination rates for inpatients but not for outpatients. Culture parameters associated with higher contamination rates included microbial growth from a single specimen, isolation of certain microbial species (eg, coagulase-negative Staphylococcus), and longer time to detect growth in culture. Contamination rates were not significantly affected by the type of blood culture method used, specimen volume, or use of a double-needle collection procedure. CONCLUSIONS: There is wide variation in blood culture contamination rates among institutions. Three specimen collection factors and three culture variables were identified as having a significant effect on blood culture contamination.

OBJECTIVE: To determine the frequency and reasons for rejection of chemistry specimens. DESIGN AND SETTING: College of American Pathologists Q-Probes laboratory quality improvement study prospectively recording rejected chemistry specimens in 453 laboratories. MAIN OUTCOME MEASURE: Percentage of submitted specimens rejected for testing. RESULTS: Of 10,709,701 chemistry specimens submitted to the participating laboratories during the data collection period, 37,208 (0.35%) were rejected prior to testing. The institutional 10th, 50th (median), and 90th percentiles were 1.35%, 0.31%, and 0.06%, respectively. The most frequent reason for rejection was hemolysis, which occurred five times more frequently than the second most cited reason, insufficient specimen quantity to perform the test. When examined with their respective frequency of use, a higher percentage of rejected specimens were collected in microcollection tubes than in other containers. When compared with the respective frequency with which they collect specimens, laboratory personnel submitted significantly fewer rejected specimens than other in-hospital personnel groups and slightly more than out-of-hospital nonlaboratory personnel. The poorest performance was demonstrated by other in-hospital nonlaboratory personnel. Serum and plasma oxalate/fluoride specimens exhibited significantly lower rejection rates when compared with the other specimen types. Relative rejection rates were higher for nongel tubes and lower for syringes when compared with gel tubes. CONCLUSION: Specimen rejection should be monitored on a regular basis. Institution-specific factors that are associated with rejection should be identified and targeted for improvement efforts. Action thresholds should be set sufficiently low to assure that continuous improvement is effected.

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.