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BACKGROUND: Emergency department (ED) visits contribute substantially to health care expenditures. Case management has been proposed as a strategy to address the medical and social needs of complex patients. However, strong research designs to evaluate the effectiveness of such interventions are limited. OBJECTIVES: To evaluate whether a community-based case management program was associated with reduced ED utilization among complex patients. DESIGN: Patients whose risk exceeded a threshold were randomly assigned to a group offered case management or to the control group. Assignment occurred at five intervals between November 2017 and January 2019. Program effectiveness for all assigned patients was assessed using an intention-to-treat effect. Program effectiveness among those who received treatment was assessed using a local average treatment effect, estimated using instrumental variables. Both estimators were adjusted for baseline characteristics using linear models. PARTICIPANTS: Adults over age 18 with at least one health care encounter with Michigan Medicine or St. Joseph Mercy Health System between June 2, 2016, and November 27, 2018. INTERVENTIONS: Intervention arm participants (n = 486) were offered coordinated case management across medical, mental health, and social service organizations. Control arm participants (n = 409) received usual care. MAIN MEASURES: The primary outcome was the number of ED visits in the 6 months following randomization into the study. Secondary outcomes were 6-month counts of inpatient and outpatient visits. KEY RESULTS: Of the 486 patients assigned to the intervention, 131 (27%) consented to receive case management. The intention-to-treat effect on ED visits was + 0.14 (95% CI: - 0.27 to + 0.55). The local average treatment effect among those who consented and received case management was + 0.53 (95% CI: - 1.00 to + 2.05). Intention-to-treat and local average treatment effects were not significant for secondary outcomes. CONCLUSIONS: The community case management intervention targeting ED visits was not associated with reduced utilization. Future case management interventions may benefit from additional patient engagement strategies and longer evaluation time periods. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT03293160.
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Administração de Caso , Serviço Hospitalar de Emergência , Adulto , Gastos em Saúde , Humanos , Saúde Mental , Avaliação de Programas e Projetos de SaúdeRESUMO
High utilizers of the Emergency Department (ED) often have complex needs that require coordination of care between multiple organizations. We describe a Learning Health Systems (LHS) approach to reducing ED visits, in which an intervention is delivered to a cohort of high utilizers identified using population-level data and predictive modeling. We focus on the development and validation of a random forest model that utilizes electronic health record data from three health systems across two counties in Michigan to predict the number of ED visits each resident will incur in the next six months. Using 5-fold cross-validation, the model achieves a root-mean-squared-error of 0.51 visits and a mean absolute error of 0.24 visits. Using time-based validation, the model achieves a root-mean-squared error of 0.74 visits and a mean absolute error of 0.29 visits. Patients projected to have high ED utilization are being enrolled in a community-wide care coordination intervention using twelve sites across two counties. We believe that the repeated cycles of modeling and intervention demonstrate an LHS in action.
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Registros Eletrônicos de Saúde , Serviço Hospitalar de Emergência/estatística & dados numéricos , Administração dos Cuidados ao Paciente , Adulto , Feminino , Humanos , Aprendizagem , Masculino , Michigan , Modelos Estatísticos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Educação de Pacientes como AssuntoRESUMO
BACKGROUND: A nationwide outbreak of fungal infections was traced to injection of Exserohilum-contaminated methylprednisolone. We describe our experience with patients who developed spinal or paraspinal infection after injection of contaminated methylprednisolone. METHODS: Data were assembled from the Michigan Department of Community Health, electronic medical records, and magnetic resonance imaging (MRI) reports. RESULTS: Of 544 patients who received an epidural injection from a contaminated lot of methylprednisolone at a pain clinic in southeastern Michigan, 153 (28%) were diagnosed at our institution with probable or confirmed spinal or paraspinal fungal infection at the injection site. Forty-one patients had both meningitis and spinal or paraspinal infection, and 112 had only spinal or paraspinal infection. Magnetic resonance imaging abnormalities included abscess, phlegmon, arachnoiditis, and osteomyelitis. Surgical debridement in 116 patients revealed epidural phlegmon and epidural abscess most often. Among 26 patients with an abnormal MRI but with no increase or change in chronic pain, 19 (73%) had infection identified at surgery. Fungal infection was confirmed in 78 patients (51%) by finding hyphae in tissues, positive polymerase chain reaction, or culture. Initial therapy was voriconazole plus liposomal amphotericin B in 115 patients (75%) and voriconazole alone in 38 patients (25%). As of January 31, 2014, 20 patients remained on an azole agent. Five patients died of infection. CONCLUSIONS: We report on 153 patients who had spinal or paraspinal fungal infection at the site of epidural injection of contaminated methylprednisolone. One hundred sixteen (76%) underwent operative debridement in addition to treatment with antifungal agents.
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Whole slide imaging (WSI), or "virtual" microscopy, involves the scanning (digitization) of glass slides to produce "digital slides". WSI has been advocated for diagnostic, educational and research purposes. When used for remote frozen section diagnosis, WSI requires a thorough implementation period coupled with trained support personnel. Adoption of WSI for rendering pathologic diagnoses on a routine basis has been shown to be successful in only a few "niche" applications. Wider adoption will most likely require full integration with the laboratory information system, continuous automated scanning, high-bandwidth connectivity, massive storage capacity, and more intuitive user interfaces. Nevertheless, WSI has been reported to enhance specific pathology practices, such as scanning slides received in consultation or of legal cases, of slides to be used for patient care conferences, for quality assurance purposes, to retain records of slides to be sent out or destroyed by ancillary testing, and for performing digital image analysis. In addition to technical issues, regulatory and validation requirements related to WSI have yet to be adequately addressed. Although limited validation studies have been published using WSI there are currently no standard guidelines for validating WSI for diagnostic use in the clinical laboratory. This review addresses the current status of WSI in pathology related to regulation and validation, the provision of remote and routine pathologic diagnoses, educational uses, implementation issues, and the cost-benefit analysis of adopting WSI in routine clinical practice.
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PURPOSE: To develop a guideline to improve the accuracy of immunohistochemical (IHC) estrogen receptor (ER) and progesterone receptor (PgR) testing in breast cancer and the utility of these receptors as predictive markers. METHODS: The American Society of Clinical Oncology and the College of American Pathologists convened an international Expert Panel that conducted a systematic review and evaluation of the literature in partnership with Cancer Care Ontario and developed recommendations for optimal IHC ER/PgR testing performance. RESULTS: Up to 20% of current IHC determinations of ER and PgR testing worldwide may be inaccurate (false negative or false positive). Most of the issues with testing have occurred because of variation in pre-analytic variables, thresholds for positivity, and interpretation criteria. RECOMMENDATIONS: The Panel recommends that ER and PgR status be determined on all invasive breast cancers and breast cancer recurrences. A testing algorithm that relies on accurate, reproducible assay performance is proposed. Elements to reliably reduce assay variation are specified. It is recommended that ER and PgR assays be considered positive if there are at least 1% positive tumor nuclei in the sample on testing in the presence of expected reactivity of internal (normal epithelial elements) and external controls. The absence of benefit from endocrine therapy for women with ER-negative invasive breast cancers has been confirmed in large overviews of randomized clinical trials.
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Neoplasias da Mama/química , Imuno-Histoquímica/normas , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Algoritmos , Biomarcadores Tumorais/análise , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Invasividade Neoplásica , Recidiva Local de Neoplasia , Reprodutibilidade dos Testes , Falha de TratamentoRESUMO
PURPOSE: To develop a guideline to improve the accuracy of immunohistochemical (IHC) estrogen receptor (ER) and progesterone receptor (PgR) testing in breast cancer and the utility of these receptors as predictive markers. METHODS: The American Society of Clinical Oncology and the College of American Pathologists convened an international Expert Panel that conducted a systematic review and evaluation of the literature in partnership with Cancer Care Ontario and developed recommendations for optimal IHC ER/PgR testing performance. RESULTS: Up to 20% of current IHC determinations of ER and PgR testing worldwide may be inaccurate (false negative or false positive). Most of the issues with testing have occurred because of variation in preanalytic variables, thresholds for positivity, and interpretation criteria. RECOMMENDATIONS: The Panel recommends that ER and PgR status be determined on all invasive breast cancers and breast cancer recurrences. A testing algorithm that relies on accurate, reproducible assay performance is proposed. Elements to reliably reduce assay variation are specified. It is recommended that ER and PgR assays be considered positive if there are at least 1% positive tumor nuclei in the sample on testing in the presence of expected reactivity of internal (normal epithelial elements) and external controls. The absence of benefit from endocrine therapy for women with ER-negative invasive breast cancers has been confirmed in large overviews of randomized clinical trials.
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Biomarcadores Tumorais , Neoplasias da Mama , Guias como Assunto , Diretrizes para o Planejamento em Saúde , Imuno-Histoquímica , Receptores de Estrogênio , Receptores de Progesterona , Feminino , Humanos , Algoritmos , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Imuno-Histoquímica/métodos , Valor Preditivo dos Testes , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Sociedades Médicas , Estados Unidos , Revisões Sistemáticas como AssuntoRESUMO
CONTEXT: Estrogen receptor and progesterone receptor status is assessed on all newly diagnosed, invasive breast carcinomas and in recurrences to determine patient eligibility for hormonal therapy, but 10% to 20% of estrogen receptor and progesterone receptor test results are discordant when tested in multiple laboratories. OBJECTIVE: To define the analytic (technical) validation requirements for estrogen receptor and progesterone receptor immunohistochemistry assays used to select patients for hormonal therapy. DATA SOURCES: Literature review and expert consensus. CONCLUSIONS: A standardized process for initial test validation is described. We believe adoption of this process will improve the accuracy of hormone-receptor testing, reduce interlaboratory variation, and minimize false-positive and false-negative results. Required ongoing assay assessment procedures are also described.
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Neoplasias da Mama/metabolismo , Diretrizes para o Planejamento em Saúde , Imuno-Histoquímica/métodos , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/metabolismo , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/metabolismoRESUMO
PURPOSE: To develop a guideline to improve the accuracy of immunohistochemical (IHC) estrogen receptor (ER) and progesterone receptor (PgR) testing in breast cancer and the utility of these receptors as predictive markers. METHODS: The American Society of Clinical Oncology and the College of American Pathologists convened an international Expert Panel that conducted a systematic review and evaluation of the literature in partnership with Cancer Care Ontario and developed recommendations for optimal IHC ER/PgR testing performance. RESULTS: Up to 20% of current IHC determinations of ER and PgR testing worldwide may be inaccurate (false negative or false positive). Most of the issues with testing have occurred because of variation in preanalytic variables, thresholds for positivity, and interpretation criteria. RECOMMENDATIONS: The Panel recommends that ER and PgR status be determined on all invasive breast cancers and breast cancer recurrences. A testing algorithm that relies on accurate, reproducible assay performance is proposed. Elements to reliably reduce assay variation are specified. It is recommended that ER and PgR assays be considered positive if there are at least 1% positive tumor nuclei in the sample on testing in the presence of expected reactivity of internal (normal epithelial elements) and external controls. The absence of benefit from endocrine therapy for women with ER-negative invasive breast cancers has been confirmed in large overviews of randomized clinical trials.
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Biomarcadores Tumorais , Neoplasias da Mama , Guias de Prática Clínica como Assunto , Receptores de Estrogênio , Receptores de Progesterona , Feminino , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Medicina Baseada em Evidências , Imuno-Histoquímica , Oncologia/normas , Valor Preditivo dos Testes , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Sensibilidade e Especificidade , Sociedades Médicas , Estados Unidos , Revisões Sistemáticas como AssuntoRESUMO
Extensive use of automation in the clinical laboratory creates the potential for systematic errors that affect a large number of patient results before the error is discovered. When a large-scale testing error is found, the approaches recommended for responding to individual medical mishaps are often inadequate. This report uses 2 case studies to illustrate some of the unique challenges facing laboratory managers confronted with a large-scale testing error. We identify 9 distinct constituencies that may be impacted by large-scale testing errors, each of which requires laboratory management's thoughtful and timely attention.
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Automação Laboratorial/métodos , Erros de Diagnóstico , Garantia da Qualidade dos Cuidados de Saúde , Humanos , Laboratórios Hospitalares , Patologia ClínicaRESUMO
INTRODUCTION: Actinomyces are slow growing, non-spore forming, gram-positive, branching bacilli that thrive in anaerobic and microareophilic conditions. Actinomyces are more commonly associated with oral and cervicofacial infections. Hepatic involvement in infections of the abdomen (known as isolated hepatic actinomycosis) is rare, accounting for only 5% of all cases of actinomycosis. CASE PRESENTATION: We present the case of a 75-year-old Caucasian woman with a 3-month history of night sweats, fever, chills, abdominal bloating, anorexia, weight-loss, and early satiety. The patient was found to have isolated hepatic actinomycosis infection after undergoing a laparotomy with a biopsy of the liver. The patient has now recovered. CONCLUSION: Isolated hepatic actinomycosis is a rare and often overlooked etiology for a liver mass. Given its subacute presentation and nondescript symptomatology, physicians should be aware of this differential and the potential pitfalls in diagnosis and management.
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CONTEXT: A variety of document control practices are required of clinical laboratories by US regulation, laboratory accreditors, and standard-setting organizations. OBJECTIVE: To determine how faithfully document control is being implemented in practice and whether particular approaches to document control result in better levels of compliance. DESIGN: Contemporaneous, structured audit of 8814 documents used in 120 laboratories for conformance with 6 generally accepted document control requirements: available, authorized, current, reviewed by management, reviewed by staff, and archived. RESULTS: Of the 8814 documents, 3113 (35%) fulfilled all 6 document control requirements. The requirement fulfilled most frequently was availability of the document at all shifts and locations (8564 documents; 97%). Only 4407 (50%) of documents fulfilled Clinical Laboratory Improvement Amendment requirements for being properly archived after updating or discontinuation. Policies and procedures were more likely to fulfill document control requirements than forms and work aids. Documents tended to be better controlled in some laboratory sections (eg, transfusion service) than in others (eg, microbiology and client services). We could not identify document control practices significantly associated with higher compliance rates. CONCLUSIONS: Most laboratories are not meeting regulatory and accreditation requirements related to control of documents. It is not clear whether control failures have any impact on the quality of laboratory results or patient outcomes.
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Técnicas de Laboratório Clínico/normas , Laboratórios Hospitalares/normas , Registros , HumanosRESUMO
CONTEXT: Monitoring customer satisfaction is a valuable component of a laboratory quality improvement program. OBJECTIVE: To survey the level of physician satisfaction with hospital clinical laboratory services. DESIGN: Participating institutions provided demographic and practice information and survey results of physician satisfaction with defined aspects of clinical laboratory services, rated on a scale of 1 (poor) to 5 (excellent). RESULTS: One hundred thirty-eight institutions participated in this study and submitted a total of 4329 physician surveys. The overall satisfaction score for all institutions ranged from 2.9 to 5.0. The median overall score for all participants was 4.1 (10th percentile, 3.6; 90th percentile, 4.5). Physicians were most satisfied with the quality/reliability of results and staff courtesy, with median values of excellent or good ratings of 89.9%. Of the 5 service categories that received the lowest percentage values of excellent/good ratings (combined scores of 4 and 5), 4 were related to turnaround time for inpatient stat, outpatient stat, routine, and esoteric tests. Surveys from half of the participating laboratories reported that 96% to 100% of physicians would recommend the laboratory to other physicians. The category most frequently selected as the most important category of laboratory services was quality/reliability of results (31.7%). CONCLUSIONS: There continues to be a high level of physician satisfaction and loyalty with clinical laboratory services. Test turnaround times are persistent categories of dissatisfaction and present opportunities for improvement.
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Atitude do Pessoal de Saúde , Técnicas de Laboratório Clínico/normas , Laboratórios Hospitalares/normas , Patologia Clínica/normas , Médicos , Indicadores de Qualidade em Assistência à Saúde , Humanos , Garantia da Qualidade dos Cuidados de Saúde , Sociedades Médicas , Fatores de TempoRESUMO
CONTEXT: Hospital accreditors are placing increased emphasis on the timeliness with which critical laboratory results are reported to caregivers. OBJECTIVE: To measure the speed of critical result notification at a group of laboratories, identify factors associated with faster reporting, and place findings in the context of the time required to transport and test specimens and to correct critical abnormalities. DESIGN: Contemporaneous review of 3545 inpatient and emergency department critical result notifications in 121 laboratories enrolled in the College of American Pathologists Q-Probes program. RESULTS: The median laboratory required a median of 5 minutes for staff to notify someone about a critical result once testing was complete. Laboratories affiliated with smaller institutions (P = .01), rural laboratories (P = .001), and sites that called results before releasing them from the laboratory computer (P = .02) were able to notify caregivers more quickly. There was variation among institutions in the time it took to notify caregivers (interquartile range, 1.5-8 minutes). At the median facility, notification took place 56.5 minutes after the specimen had been collected. CONCLUSIONS: The time required to notify caregivers of a critical laboratory result is a small proportion of the time taken to collect and test specimens or the time that has been reported for caregivers to correct abnormalities. Although failure to notify caregivers of critical results may represent an important patient safety vulnerability, the timeliness of laboratory notification is a minor contributor to total test turnaround time at most institutions.
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Benchmarking/normas , Comunicação , Laboratórios Hospitalares/normas , Serviço Hospitalar de Patologia/normas , Garantia da Qualidade dos Cuidados de Saúde/normas , Cuidadores , Relações Hospital-Médico , Humanos , Prontuários Médicos/normas , Prontuários Médicos/estatística & dados numéricos , Controle de Qualidade , Fatores de Tempo , Estados UnidosRESUMO
CONTEXT: Errors entering orders for send-out laboratory tests into computer systems waste health care resources and can delay patient evaluation and management. OBJECTIVES: To determine (1) the accuracy of send-out test order entry under "real world" conditions and (2) whether any of several practices are associated with improved order accuracy. DESIGN: Representatives from 97 clinical laboratories provided information about the processes they use to send tests to reference facilities and their order entry and specimen routing error rates. RESULTS: In aggregate, 98% of send-out tests were correctly ordered and 99.4% of send-out tests were routed to the proper reference laboratory. There was wide variation among laboratories in the rate of send-out test order entry errors. In the bottom fourth of laboratories, more than 5% of send-out tests were ordered incorrectly, while in the top fourth of laboratories fewer than 0.3% of tests were ordered incorrectly. Order entry errors were less frequent when a miscellaneous test code was used than when a specific test code was used (3.9% vs 5.6%; P = .003). CONCLUSIONS: Computer order entry errors for send-out tests occur approximately twice as frequently as order entry errors for other types of tests. Filing more specific test codes in a referring institution's information system is unlikely to reduce order entry errors and may make error rates worse.
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Sistemas de Informação em Laboratório Clínico/normas , Erros Médicos/estatística & dados numéricos , Sistemas Computadorizados de Registros Médicos/normas , Patologia Clínica/normas , Garantia da Qualidade dos Cuidados de Saúde , Humanos , Erros Médicos/prevenção & controle , Estudos Retrospectivos , Sociedades Médicas , Inquéritos e Questionários , Estados UnidosRESUMO
CONTEXT: Eighty-two million surgical pathology and cytology reports were issued in the United States during 2007; a subset of these reports will be misunderstood by readers. Recent attention has focused on standardizing the content of pathology reports, particularly for common malignancies, to facilitate transmission of required information. Comparatively little attention has been focused on the format of reports--the arrangement of headlines, text blocks, and other report elements to optimize communication. OBJECTIVE: To provide guidance to report designers and authors about how to format reports to maximize the speed, fidelity, and ease of information transfer. DATA SOURCES: Review of relevant literature from commercial publishing and aviation and the fields of cognitive psychology and pathology, supplemented with an analysis of 10,000 pathology reports and the author's personal experience as a practicing pathologist. CONCLUSIONS: Four evidence-based and time-tested principles can help pathologists format information to communicate more effectively: (1) use of diagnostic headlines to emphasize key points, (2) maintenance of layout continuity with other reports and over time, (3) optimization of information density for readers, and (4) reduction of extraneous information or "clutter." Practical advice is also provided to help pathologists minimize corruption of formatting as reports are transmitted electronically between medical information systems.
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Barreiras de Comunicação , Compreensão , Patologia Clínica/métodos , Patologia Cirúrgica/métodos , Registros , Medicina Baseada em Evidências , Humanos , MEDLINERESUMO
CONTEXT: Standards have been developed for establishing reference intervals, but little is known about how intervals are determined in practice, interlaboratory variation in intervals, or errors that occur while setting reference intervals. OBJECTIVES: To determine (1) methods used by clinical laboratories to establish reference intervals for 7 common analytes, (2) variation in intervals, and (3) factors that contribute to establishment of "outlier" intervals. DESIGN: One hundred sixty-three clinical laboratories provided information about their reference intervals for potassium, calcium, magnesium, thyroid-stimulating hormone, hemoglobin, platelet count, and activated partial thromboplastin time. RESULTS: Approximately half the laboratories reported conducting an internal study of healthy individuals to validate reference intervals for adults. Most laboratories relied on external sources to establish reference intervals for pediatric patients. There was slight variation in intervals used by the central 80% of study laboratories, but some laboratories outside the central 80% had surprisingly low and high limits for their reference intervals. In some cases the intervals used by 2 laboratories had no overlap. For example, one laboratory considered a hemoglobin of 13.8 g/dL in a woman to be "low" while another considered the same value to be "high." Three percent of reference intervals contained a limit that qualified as an "outlier" using standard statistical tests; we could not identify any practice associated with adoption of outlier intervals. CONCLUSIONS: Many laboratories adopt reference intervals from manufacturers without on-site testing of healthy individuals. Reference intervals used by facilities that forgo on-site testing are not statistically different from intervals validated with on-site studies.
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Análise Química do Sangue/normas , Testes Hematológicos/normas , Laboratórios/normas , Valores de Referência , Adulto , Criança , Técnicas de Laboratório Clínico/normas , Coleta de Dados , Feminino , Humanos , Masculino , Análise MultivariadaRESUMO
Benchmarking is an important part of performance evaluation in the clinical laboratory. When used effectively, benchmarking can lead to significant changes and performance improvement. This article reviews the experience of the College of American Pathologists (CAP) with benchmarking clinical laboratory expenses and presents data that summarizes recent laboratory trends identified through CAP's benchmark data.
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Benchmarking , Laboratórios/normas , Custos e Análise de Custo , Humanos , Laboratórios/economia , Organizações de Normalização Profissional , Controle de Qualidade , Estados UnidosRESUMO
CONTEXT: Misidentified laboratory specimens may cause patient injury, but their frequency in general laboratory practice is unknown. OBJECTIVES: To determine (1) the frequency of identification errors detected before and after result verification, (2) the frequency of adverse patient events due to specimen misidentification, and (3) factors associated with lower error rates and better detection of errors. DESIGN: One hundred twenty clinical laboratories provided information about identification errors during 5 weeks. RESULTS: In aggregate, 85% of errors were detected before results were released; one quarter of laboratories identified more than 95% of errors before result verification. The overall rate of patient identification errors involving released results was 55 errors per 1,000,000 billable tests. A total of 345 adverse events were reported. Most of the adverse events caused material inconvenience to the patients but did not result in any permanent harm. On average, adverse events resulted from 1 of every 18 identification errors. Extrapolating the adverse event rate observed in this study to all United States hospital-based laboratories suggests that more than 160,000 adverse events per year result from misidentification of patients' laboratory specimens. CONCLUSIONS: Identification errors are common in laboratory medicine, but most are detected before results are released, and only a fraction are associated with adverse patient events. Even when taking into consideration the design of this study, which used imperfect case finding, institutions that did a better job of detecting errors within the laboratory released a smaller proportion of results that involved specimen misidentification.