The clinical and economic implications of specimen provenance complications in diagnostic prostate biopsies

PURPOSE

Inaccurate diagnoses of prostate cancer can result from transposition or contamination of patient biopsy specimens, which are known as specimen provenance complications. We assessed the clinical and economic burden of specimen provenance complications in prostate biopsies in the United States.

MATERIALS AND METHODS

We performed a comprehensive, systematic review of the literature to approximate the effect of specimen provenance complications on direct medical costs, patient QALYs and medicolegal costs. Data were extracted from published studies on specimen provenance complications rates, prostate cancer treatment efficacy, treatment cost, litigation/settlement costs after false diagnoses of prostate biopsies and patient quality of life. Sensitivity analysis was done to identify factors that most influenced the outcomes and assess the robustness of the findings.

RESULTS

Of the estimated 806,251 primary and secondary prostate biopsies performed annually in the United States 20,322 specimen provenance complications were projected to result in 4,570 clinically meaningful false diagnoses and an expected loss of 634 QALYs. The total burden of specimen provenance complications was projected to exceed $879.9 million or $3,776 per positive cancer diagnosis. This estimate was most sensitive to the indemnity cost per false-positive case and the rate of transpositions at independent reference laboratories.

CONCLUSIONS

The societal burden of specimen provenance complications in patients who undergo prostate biopsy exceeds $880 million annually in the United States. This analysis framework may be useful as policy makers, health organizations and researchers seek to decrease false diagnoses of prostate cancer and the consequent effects of delayed or unnecessary treatment. Further study is warranted to quantify the economic burden among additional diseases.

Could light meal jeopardize laboratory coagulation tests?

BACKGROUND

Presently the necessity of fasting time for coagulation tests is not standardized. Our hypothesis is that this can harm patient safety. This study is aimed at evaluating whether a light meal (i.e. breakfast) can jeopardize laboratory coagulation tests.

MATERIALS AND METHODS

A blood sample was firstly collected from 17 fasting volunteers (12 h). Immediately after blood collection, the volunteers consumed a light meal. Then samples were collected at 1, 2 and 4 h after the meal. Coagulation tests included: activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen (Fbg), antithrombin III (AT), protein C (PC) and protein S (PS). Differences between samples were assessed by Wilcoxon ranked-pairs test. The level of statistical significance was set at P < 0.05. Mean % differences were determined and differences between and baseline and 1, 2 and 4h samples were compared with reference change value (RCV).

RESULTS

A significantly higher % activity of AT was observed at 1 h and 4 h after meal vs. baseline specimen [113 (104-117) and 111 (107-120) vs. 109 (102-118), respectively; P = 0.029 and P = 0.016]. APTT at 2 h was found significantly lower than baseline samples [32.0 (29.9-34.8) vs. 34.1 (32.2-35.2), respectively; P = 0.041]. The results of both Fbg and PS tests were not influenced by a light meal. Furthermore, no coagulation tests had significant variation after comparison with RCV.

CONCLUSION

A light meal does not influence the laboratory coagulation tests we assessed, but we suggest that the laboratory quality managers standardize the fasting time for all blood tests at 12 hours, to completely metabolize the lipids intake.

Pulmonary artery sarcoma mimicking pulmonary embolism

Primary sarcomas that arise from major blood vessels are exceedingly rare, and some of the published cases have been autopsy reports. Most patients are adults. We report a case of pulmonary artery sarcoma in a 77-year-old man who presented with acute onset of dyspnea. Magnetic resonance imaging of the chest revealed a large mass within the pulmonary trunk and its main branches. Because massive pulmonary embolism was suspected, both anticoagulant and thrombolytic therapies were initiated. The patient responded poorly to these therapies, which then necessitated resection of both the mass and the pulmonary valve. A bioprosthetic porcine valve replaced the native valve, and we reconstructed the right ventricular outflow tract with a Dacron patch. Histopathologic examination revealed a high-grade sarcoma with focal myogenic and chondrogenic differentiation. The patient tolerated the procedure well and was discharged from the hospital on postoperative day 7. He was subsequently treated with chemotherapy and radiation and continued to show no evidence of disease. The diagnosis of pulmonary artery sarcoma should be suspected in patients who present with manifestations of pulmonary embolism, especially when there is no evidence of deep venous thrombosis and poor response to anticoagulant therapy. Multimodal therapy can provide prolonged survival.

Left ventricular to right atrial shunt (Gerbode defect): congenital versus acquired

Introduction

Congenital left ventricular to right atrial (LV-RA) shunt (Gerbode defect) is rare, while acquired LV-RA shunt has been increasingly reported. As yet, systematically incorporated data of the LV-RA shunt have not been presented.

Aim

To present the clinical features, diagnostic challenge and management strategies of congenital and acquired LV-RA shunts.

Material and methods

The data source was based on a comprehensive literature retrieval of the LV-RA shunt in the period 1990–2013.

Results

In comparison with the acquired Gerbode defect, the congenital Gerbode defect group of patients were younger and were associated more often with additional congenital disorders. Previous cardiac surgery and infective endocarditis were the two major aetiologies of the occurrence of the acquired shunts. Paravalvular abscess was associated in 10.2% and atrioventricular block in 13.6% of the acquired group patients. Transoesophageal echocardiography showed a higher diagnostic accuracy, lower missed diagnosis and lower inclusive diagnosis rates, in comparison to transthoracic echocardiography, but the misdiagnosis rates of the two modalities did not differ from each other. Four (4.5%) of the acquired group patients were complicated by atrioventricular block following surgical or interventional closure of the shunt. Eight (9.1%) patients died in the acquired group, but no patient died in the congenital group.

Conclusions

The diagnosis of an LV-RA shunt is quite challenging, especially in the context of coexisting abnormalities including an additional intracardiac shunt, tricuspid regurgitation, pulmonary artery hypertension and infective endocarditis, which have to be carefully differentiated from the shunt by further investigations. A better control of infective complications and careful manoeuvres during surgery may help to keep the LV-RA-sensitive septum intact.

Subjective cognitive complaints contribute to misdiagnosis of mild cognitive impairment

Subjective cognitive complaints are a criterion for the diagnosis of mild cognitive impairment (MCI), despite their uncertain relationship to objective memory performance in MCI. We aimed to examine self-reported cognitive complaints in subgroups of the Alzheimer's Disease Neuroimaging Initiative (ADNI) MCI cohort to determine whether they are a valuable inclusion in the diagnosis of MCI or, alternatively, if they contribute to misdiagnosis. Subgroups of MCI were derived using cluster analysis of baseline neuropsychological test data from 448 ADNI MCI participants. Cognitive complaints were assessed via the Everyday Cognition (ECog) questionnaire, and discrepancy scores were calculated between self- and informant-report. Cluster analysis revealed Amnestic and Mixed cognitive phenotypes as well as a third Cluster-Derived Normal subgroup (41.3%), whose neuropsychological and cerebrospinal fluid (CSF) Alzheimer's disease (AD) biomarker profiles did not differ from a "robust" normal control group. This cognitively intact phenotype of MCI participants overestimated their cognitive problems relative to their informant, whereas Amnestic MCI participants with objective memory impairment underestimated their cognitive problems. Underestimation of cognitive problems was associated with positive CSF AD biomarkers and progression to dementia. Overall, there was no relationship between self-reported cognitive complaints and objective cognitive functioning, but significant correlations were observed with depressive symptoms. The inclusion of self-reported complaints in MCI diagnostic criteria may cloud rather than clarify diagnosis and result in high rates of misclassification of MCI. Discrepancies between self- and informant-report demonstrate that overestimation of cognitive problems is characteristic of normal aging while underestimation may reflect greater risk for cognitive decline.

Preoperatively misclassified, surgically removed benign renal masses: a systematic review of surgical series and United States population level burden estimate

PURPOSE

A significant proportion of renal masses removed for suspected malignancy are histologically benign with the probability inversely proportional to lesion size. To our knowledge the number of preoperatively misclassified benign renal masses treated with nephrectomy is currently unknown. Given the increasing incidence and decreasing average size of renal cell carcinoma, this burden is likely increasing. We estimated the population level burden of surgically removed, preoperatively misclassified benign renal masses in the United States.

MATERIALS AND METHODS

We systematically reviewed the literature for studies of pathological findings of renal masses removed for suspected renal cell carcinoma based on preoperative imaging through July 1, 2014. We excluded studies that did not describe benign pathology and with masses not stratified by size, and in which pathology results were based on biopsy. SEER data were queried for the incidence of surgically removed renal cell carcinomas in 2000 to 2009.

RESULTS

A total of 19 studies of tumor pathology based on size met criteria for review. Pooled estimates of the proportion of benign histology in our primary analysis (American studies only and 1 cm increments) were 40.4%, 20.9%, 19.6%, 17.2%, 9.2% and 6.4% for tumors less than 1, 1 to less than 2, 2 to less than 3, 3 to less than 4, 4 to 7 and greater than 7, respectively. The estimated number of surgically resected benign renal masses in the United States from 2000 to 2009 increased by 82% from 3,098 to 5,624.

CONCLUSIONS

These estimates suggest that the population level burden of preoperatively misclassified benign renal masses is substantial and increasing rapidly, paralleling increases in surgically resected small renal cell carcinoma. This study illustrates an important and to our knowledge previously unstudied dimension of overtreatment that is not directly quantified in contemporary surveillance data.

Clinical impact of extending after-hours radiology coverage for emergency department computed tomography imaging

Background

Academic emergency departments (EDs) are often reliant on preliminary interpretation by radiology residents for after-hours computed tomography (CT) images. Identifying residents’ errors in diagnostic interpretation and ensuring appropriate contact with affected patients are areas of continuing concern.

Objective

The Mount Sinai Hospital ED and Medical Imaging Department in Toronto, Canada sought to examine the clinical impact of extending reporting hours of senior attending radiologists for ED patients undergoing CT imaging.

Methods

All evening CT studies were read by the on-call sub-specialist staff radiologist before 10 pm; while studies done after 10 pm were read by 8 am, permitting review of final reports by the ordering ED physician. A retrospective review of radiology and ED metrics was performed on ED patients undergoing CT imaging 12 weeks before and 12 weeks after implementation of the extended reading hours.

Results

In the 12 weeks prior to implementation of extended senior attending radiologist coverage, 871 CT scans were performed as compared to 944 CT scans after implementation. Time from performance of CT scan to obtaining a dictated report decreased from 10.4 hours to 2.8 hours (P<0.001), and time from performance of CT scan to report verification by the radiologist decreased from 29.7 hours to 9.4 hours (P<0.001). There were no statistically significant changes in ED length of stay, rates of admission, or rates of consultation. However, there was a significant reduction in (median) time taken for ED physicians to resolve discrepant reports in the radiology information system queue (20.7 hours versus 13.3 hours, P<0.001).

Conclusion

The extension of reporting hours reduced the time for ED physicians to review discrepant reports, while balancing educational needs of residents. This project has been considered a success by stakeholders and has now been implemented on a permanent basis.

Missed diagnosis of stroke in the emergency department: a cross-sectional analysis of a large population-based sample

Background

Some cerebrovascular events are not diagnosed promptly, potentially resulting in death or disability from missed treatments. We sought to estimate the frequency of missed stroke and examine associations with patient, emergency department (ED), and hospital characteristics.

Methods

Cross-sectional analysis using linked inpatient discharge and ED visit records from the 2009 Healthcare Cost and Utilization Project State Inpatient Databases and 2008–2009 State ED Databases across nine US states. We identified adult patients admitted for stroke with a treat-and-release ED visit in the prior 30 days, considering those given a non-cerebrovascular diagnosis as probable (benign headache or dizziness diagnosis) or potential (any other diagnosis) missed strokes.

Results

There were 23,809 potential and 2243 probable missed strokes representing 12.7% and 1.2% of stroke admissions, respectively. Missed hemorrhages (n = 406) were linked to headache while missed ischemic strokes (n = 1435) and transient ischemic attacks (n = 402) were linked to headache or dizziness. Odds of a probable misdiagnosis were lower among men (OR 0.75), older individuals (18–44 years [base]; 45–64:OR 0.43; 65–74:OR 0.28; ≥ 75:OR 0.19), and Medicare (OR 0.66) or Medicaid (OR 0.70) recipients compared to privately insured patients. Odds were higher among Blacks (OR 1.18), Asian/Pacific Islanders (OR 1.29), and Hispanics (OR 1.30). Odds were higher in non-teaching hospitals (OR 1.45) and low-volume hospitals (OR 1.57).

Conclusions

We estimate 15,000–165,000 misdiagnosed cerebrovascular events annually in US EDs, disproportionately presenting with headache or dizziness. Physicians evaluating these symptoms should be particularly attuned to the possibility of stroke in younger, female, and non-White patients.

Comparison between an automated device and a manual mercury sphygmomanometer in an epidemiological survey of hypertension prevalence

BACKGROUND

Automated devices (AD) for measuring blood pressure (BP) are gradually replacing mercury sphygmomanometers (MM) in clinical settings. However, the use of ADs in epidemiological surveys has not been established. We investigated the factors associated with measurement differences when using an MM and an AD.

METHODS

Two trained observers took three BP measurements in 454 subjects as part of an epidemiological survey, alternately using an MM and an AD. BP measurement difference was defined as BPMM - BPAD. Alarm reactions (ARs) were calculated by subtracting the third systolic BP (SBP) measurement from the first SBP.

RESULTS

The mean age of subjects was 50.7±15.4 years (n = 454). The mean BPs using the MM and the AD were 119.8±13.9 vs. 119.5±13.6mm Hg in males and 115.0±16.8 vs. 111.6±15.7mm Hg in females for SBP and 77.7±10.4 vs. 74.7±10.4mm Hg in males and 73.2±9.3 vs. 69.9±10.3mm Hg in females for diastolic BP (DBP). Age, gender, arm circumference, and AR were the factors related to the difference. The concordance correlation coefficients for SBP and DBP were 0.8914 (95% confidence interval [CI], 0.8727-0.9102) and 0.8207 (95% CI, 0.7920-0.8494). The kappa values for the diagnosis of hypertension and Joint National Committee 7 BP classification were 0.6538 (0.5436-0.7641) and 0.5703 (0.5055-0.6351), respectively. The diagnostic sensitivity for hypertension was 59.0%.

CONCLUSIONS

Age, gender, arm circumference, and AR were the factors related to the differences. Despite small differences in the mean values, the agreement and reliability were not good enough to recommend the A&D UA-767PC for adoption in epidemiological surveys of hypertension prevalence.

Periodontal probing versus radiographs for the diagnosis of furcation involvement

BACKGROUND

Decisions in periodontal therapy for multirooted teeth are essentially based on accurate diagnosis of the furcation involvement (FI). Furcation probing (FP) is still the basic diagnostic measure, although the assessment may be difficult. The aim of this study is to evaluate the validity of FP and radiographic assessment of FI compared with visual assessment during open flap surgery (OFS).

METHODS

In this retrospective clinical cohort study, 215 participants with periodontal disease and at least one molar treated with OFS were enrolled, and a total of 834 molars were assigned for FI by FP and in radiographs analyzed by an experienced (EE) and less experienced examiner (LE). For the investigation, 143 panoramic radiographs (OPGs) and 77 intra-oral radiographs (I-Os) were evaluated.

RESULTS

The Class of FI by FP was confirmed in 56%, whereas 15% were overestimated and 29% underestimated. FI Class 0 and I had been detected with high probability (74% and 54%, respectively). Of all FI Class III, 57% were detected correctly by radiographs and 32% by FP. FP and OFS revealed a weighted κ-coefficient (κw) = 0.588; radiographs and OFS had κw = 0.542 (OPG κw = 0.555 and I-O κw = 0.521). The interrater reliability for radiographs was dependent on the experience of the examiner (EE κw = 0.618; LE κw = 0.426).

CONCLUSIONS

Experience in analyzing conventional radiographs increases the potential of correct diagnosis of advanced FI. The reliability of FP compared with radiographic assessment depends on the anatomy and location of the tooth. Both diagnostic tools should be used in cases of suspected FI.

A unified conceptual model for diagnostic errors: underdiagnosis, overdiagnosis, and misdiagnosis

Progress in diagnostic error research has been hampered by a lack of unified terminology and definitions. This article proposes a novel framework for considering diagnostic errors, offering a unified conceptual model for underdiagnosis, overdiagnosis, and misdiagnosis. The model clarifies the critical separation between 'diagnostic process failures' (incorrect workups) and 'diagnosis label failures' (incorrect diagnoses). By dividing processes into those that are substandard, suboptimal, or optimal, important distinctions are drawn between 'preventable', 'reducible,' and 'unavoidable' diagnostic errors. The new model emphasizes the importance of mitigating diagnosis-related harms, regardless of whether the solutions require traditional safety strategies (preventable errors), more effective evidence dissemination (reducible errors; harms from overtesting and overdiagnosis), or new scientific discovery (currently unavoidable errors). Doing so maximizes our ability to prioritize solving various diagnosis-related problems from a societal value perspective. This model should serve as a foundation for developing consensus terminology and operationalized definitions for relevant diagnostic-error categories.

Perspectives from a pediatrician about diagnostic errors

This opinion paper provides perspectives from a pediatrician about diagnostic challenges in caring for children. This essay shares personal experiences and lessons learned from a pediatric hospitalist about caring for children and making errors in diagnosis. This piece offers guidance about how to teach medical learners key concepts about error in diagnosis with underscoring the importance of developing critical thinking skills. Finally, the author offers tips from the literature about how physicians and other care providers can reorganize their own thinking (metacognition) to address their clinical practice.

What can be done to increase the use of diagnostic decision support systems?

This essay explores the reasons why diagnostic decision support systems are underutilized despite growing concern about diagnostic errors. Factors related to the motivation to use the systems, clinician cognition, system design and implementation, as well as the absence of feedback in routine clinical care are discussed. Suggestions for design and implementation strategies for diagnostic decision support systems that can increase appropriate utilization are discussed.

Laboratory-associated and diagnostic errors: a neglected link

Clinical laboratories play a vital role in patient care, but many diagnostic errors are associated with laboratory testing. The past decades have seen sustained improvements in analytical performances but the error rates, particularly in pre- and post-analytical phases is still high. Although the seminal concept of the brain-to-brain laboratory loop has been described more than four decades ago, the awareness about the importance of extra-analytical aspects in laboratory quality is a recent achievement. According to this concept, all phases and activities of the testing cycle should be assessed, monitored and improved in order to decrease the total error rates and thereby improve patient safety. In the interests of patients, any direct or indirect negative consequence related to a laboratory test must be considered, irrespective of which step is involved and whether the error depends on a laboratory professional (e.g., calibration or testing error) or a non-laboratory operator (e.g., inappropriate test request, error in patient identification and/or blood collection). Data collected in various clinical settings demonstrate that many diagnostic errors are associated with laboratory testing. In particular, errors are due to inappropriate test request and/or result interpretation and utilization. Collaborations between laboratory professionals and other care providers, namely clinicians and nurses, are needed to achieve the goal of improved patient safety.

Retrospective blinded review of interpretational diagnostic discrepancies in surgical pathology: 18 years of experience at a tertiary care facility

We evaluated our quality assurance (QA) methods and QA consensus conference model for assessing the rate of interpretational diagnostic errors and trend of errors. Using monthly QA reports from review of frozen section- permanent section correlation and amended reports, all cases with interpretational diagnostic errors were identified. Retrospective blinded review of study cases were independently performed by all staff pathologist and subsequently discussed in QA conference sessions. 277 (.07%) interpretational errors were identified from 1993-2010. Errors with patient consequences comprised 15% of all errors, 4% of which were major errors. More than half (57%) of the errors were identified on review of frozen section- permanent section correlation and accounted for 64 % of all errors with patient consequence and 45% of major errors. Comparison of errors between two equally divided time periods (1993-2001 and 2002-2010) showed significant error reduction (p< 0.05). 64% of all errors, 61% of errors with patient consequence and 73% of major errors were a consequence of incorrect interpretation of the biologic behavior of the neoplasm. To conclude, we propose this quality assurance model as an effective tool for assessing interpretational errors, particularly those with significant patient consequences, enhancing participation of pathologists and reducing errors.

Past suicide attempts in depressed inpatients: clinical versus research assessment

The objective of this study was to compare structured clinical assessment versus research measurement of suicidal risk among inpatients with major depression. Fifty depressed inpatients underwent a structured clinical and an independent research assessment of suicidal risk. Agreement between both assessments and its impact upon time to first readmission was tested. A false negative rate of 25% in the clinical screening of past suicide attempts was associated with older age, concealment, and reported lower frequency of suicidal thoughts. Mean times to first readmission (2.5 years follow-up) were 74 weeks (discordant responders) and 118 weeks (concordant responders). A failure to detect 25% of patients with past suicide attempt history in the clinical assessment was associated with older age and concealment of suicidal thoughts.

The MPATH-Dx reporting schema for melanocytic proliferations and melanoma

BACKGROUND

The histologic diagnosis of melanoma and nevi can be subject to discordance and errors, potentially leading to inappropriate treatment and harm. Diagnostic terminology is not standardized, creating confusion for providers and patients and challenges for investigators.

OBJECTIVE

We sought to describe the development of a pathology reporting form for more precise research on melanoma and a diagnostic-treatment mapping tool for improved patient care and consistency in treatment.

METHODS

Three dermatopathologists independently reviewed melanocytic lesions randomly selected from a dermatopathology database. Melanocytic Pathology Assessment Tool and Hierarchy for Diagnosis (MPATH-Dx) reporting schema evolved from iterative case review and form revision.

RESULTS

Differences in diagnostic thresholds, interpretation, and nomenclature contributed to development of the MPATH-Dx histology reporting form, which groups lesions by similarities in histogenesis and degrees of atypia. Because preliminary results indicate greater agreement regarding suggested treatments than for specific diagnoses, the diverse terminologies of the MPATH-Dx histology reporting form were stratified by commonalities of treatments in the MPATH-Dx diagnostic-treatment mapping scheme.

LIMITATIONS

Without transformative advances in diagnostic paradigms, the interpretation of melanocytic lesions frequently remains subjective.

CONCLUSIONS

The MPATH-Dx diagnostic-treatment mapping scheme could diminish confusion for those receiving reports by categorizing diverse nomenclature into a hierarchy stratified by suggested management interventions.

Impact of miscuffing during home blood pressure measurement on the prevalence of masked hypertension

BACKGROUND

Masked hypertension has been associated with obesity. However, because most studies do not mention the specific cuff size used for home measurements, masked hypertension prevalence may have been overestimated in obese patients because of undersized cuffs. In this prospective, observational study, the effect of miscuffing on hypertension status was evaluated in patients with large arms.

METHODS

Fifty-three patients with an upper-arm circumference >33cm, undergoing treatment for mild-to-moderate hypertension, took 2 sets of home blood pressure (BP) measurements (standard vs. large cuff) using the validated Microlife BP A100 Plus automated device.

RESULTS

Mean BP was 143/85mm Hg at the office using a large cuff, 141/84mm Hg at home using a standard cuff, and 134/80mm Hg at home using a large cuff. Standard vs. large cuff home BP mean differences were 6.9mm Hg (95% confidence interval (CI) = 4.7-9.2; P < 0.0001) for systolic BP and 4.0mm Hg (95% CI = 2.4-5.5; P < 0.0001) for diastolic BP. Hypertension status differed significantly between standard vs. large cuffs: sustained hypertension (56.6% vs. 41.5%, respectively; P = 0.002), controlled hypertension (20.8% vs. 28.3%, respectively; P = 0.04), white coat hypertension (7.5% vs. 22.6%, respectively; P = 0.002), masked hypertension (15.1% vs. 7.5%, respectively; P = 0.04).

CONCLUSIONS

In patients with large arms, use of an appropriately sized large cuff for home BP measurements led to a 2-fold reduction in masked hypertension. Regarding clinical and epidemiological implications, future studies investigating masked hypertension should specify cuff size for home BP measurements. The low market availability and increased cost of large cuffs should also be addressed.

Automated detection of heuristics and biases among pathologists in a computer-based system

The purpose of this study is threefold: (1) to develop an automated, computer-based method to detect heuristics and biases as pathologists examine virtual slide cases, (2) to measure the frequency and distribution of heuristics and errors across three levels of training, and (3) to examine relationships of heuristics to biases, and biases to diagnostic errors. The authors conducted the study using a computer-based system to view and diagnose virtual slide cases. The software recorded participant responses throughout the diagnostic process, and automatically classified participant actions based on definitions of eight common heuristics and/or biases. The authors measured frequency of heuristic use and bias across three levels of training. Biases studied were detected at varying frequencies, with availability and search satisficing observed most frequently. There were few significant differences by level of training. For representativeness and anchoring, the heuristic was used appropriately as often or more often than it was used in biased judgment. Approximately half of the diagnostic errors were associated with one or more biases. We conclude that heuristic use and biases were observed among physicians at all levels of training using the virtual slide system, although their frequencies varied. The system can be employed to detect heuristic use and to test methods for decreasing diagnostic errors resulting from cognitive biases.

Errors made in the ultrasound diagnostics of the spleen

Ultrasonography, like any imaging method, entails the risk of errors. From among all means of imaging, it is the most subjective and dependent on the examiner's knowledge and experience. This paper presents the causes of examiner-dependent errors as well as those which result from technical settings and preparation of the patient for the examination. Moreover, the authors discuss the most frequent errors in the diagnosis of splenic conditions, which result from insufficient knowledge concerning anatomical variants of this organ, wrong measurements and incorrect examination technique. The mistakes made in the differentiation of focal lesions of the spleen and its hilum are also discussed. Additionally, the differentiation of collateral circulation, lymph nodes and accessory spleens is mentioned. The authors also draw attention to erroneous interpretation of the left liver lobe as a fragment of the spleen as well as the prominent tail of the pancreas filled with gastric contents and intestinal loops as abnormal masses or fluid cisterns in the area of the splenic hilum. Furthermore, the pathologies of the hilum are discussed such as tumors of the splenic flexure of the colon, lesions arising from the left kidney or the left adrenal gland. The authors list characteristic imaging features of the most common focal lesions visualized in a standard ultrasound scan as well as enhancement patterns appearing in contrast-enhanced examinations. The article discusses the features and differentiation of, among others, infarction, splenic cysts including hydatid ones, abscesses and angiomas. The ultrasound appearance of lymphoma and secondary involvement of the spleen by other malignant neoplasms is also mentioned. Moreover, the authors provide useful tips connected with imaging techniques and interpretation of the findings. The ultrasound examination carried out in compliance with current standards allows for an optimal assessment of the organ and reduction of the error-making risk. This article is based on the publication of the experts from the Polish Ultrasound Society of 2005 and updated with the latest findings in pertinent literature. The photographic documentation, which provides images of the discussed lesions, is attached to this article.

Types and origins of diagnostic errors in primary care settings

IMPORTANCE

Diagnostic errors are an understudied aspect of ambulatory patient safety.

OBJECTIVES

To determine the types of diseases missed and the diagnostic processes involved in cases of confirmed diagnostic errors in primary care settings and to determine whether record reviews could shed light on potential contributory factors to inform future interventions.

DESIGN

We reviewed medical records of diagnostic errors detected at 2 sites through electronic health record-based triggers. Triggers were based on patterns of patients' unexpected return visits after an initial primary care index visit.

SETTING

A large urban Veterans Affairs facility and a large integrated private health care system.

PARTICIPANTS

Our study focused on 190 unique instances of diagnostic errors detected in primary care visits between October 1, 2006, and September 30, 2007.

MAIN OUTCOME MEASURES

Through medical record reviews, we collected data on presenting symptoms at the index visit, types of diagnoses missed, process breakdowns, potential contributory factors, and potential for harm from errors.

RESULTS

In 190 cases, a total of 68 unique diagnoses were missed. Most missed diagnoses were common conditions in primary care, with pneumonia (6.7%), decompensated congestive heart failure (5.7%), acute renal failure (5.3%), cancer (primary) (5.3%), and urinary tract infection or pyelonephritis (4.8%) being most common. Process breakdowns most frequently involved the patient-practitioner clinical encounter (78.9%) but were also related to referrals (19.5%), patient-related factors (16.3%), follow-up and tracking of diagnostic information (14.7%), and performance and interpretation of diagnostic tests (13.7%). A total of 43.7% of cases involved more than one of these processes. Patient-practitioner encounter breakdowns were primarily related to problems with history-taking (56.3%), examination (47.4%), and/or ordering diagnostic tests for further workup (57.4%). Most errors were associated with potential for moderate to severe harm.

CONCLUSIONS AND RELEVANCE

Diagnostic errors identified in our study involved a large variety of common diseases and had significant potential for harm. Most errors were related to process breakdowns in the patient-practitioner clinical encounter. Preventive interventions should target common contributory factors across diagnoses, especially those that involve data gathering and synthesis in the patient-practitioner encounter.

Errors and mistakes in the ultrasound diagnostics of the liver, gallbladder and bile ducts

Ultrasonography is the most widespread imaging technique used in the diagnostics of the pathologies concerning the organs in the abdominal cavity. Similarly to other diagnostic tools, errors may occur in ultrasound examinations. They generally result from inappropriate techniques, which do not conform to current standards, or erroneous interpretation of obtained images. A significant portion of mistakes is caused by inappropriate quality of the apparatus, the presence of sonographic imaging artifacts, unfavorable anatomic variants or improper preparation of the patient for the examination. This article focuses on the examiner-related errors. They concern the evaluation of the liver size, echostructure and arterial and venous vascularization as well as inappropriate interpretation of the liver anatomic variants and the vascular and ductal structures localized inside of it. Furthermore, the article presents typical mistakes made during the diagnosis of the most common gallbladder and bile duct diseases. It also includes helpful data concerning differential diagnostics of the described pathologies of the liver, gallbladder and bile ducts. The article indicates the most frequent sources of mistakes as well as false negative and false positive examples which result from these errors. What is more, the norms used in the liver, gallbladder and bile duct evaluations are presented as well as some helpful guidelines referring to the exam techniques and image interpretation, which allows for reducing the error-making risk. The article has been prepared on the basis of the report published in 2005 by the Polish experts in the field of ultrasonography and extended with the latest findings obtained from the pertinent literature.

Medical errors in primary care clinics--a cross sectional study

BACKGROUND

Patient safety is vital in patient care. There is a lack of studies on medical errors in primary care settings. The aim of the study is to determine the extent of diagnostic inaccuracies and management errors in public funded primary care clinics.

METHODS

This was a cross-sectional study conducted in twelve public funded primary care clinics in Malaysia. A total of 1753 medical records were randomly selected in 12 primary care clinics in 2007 and were reviewed by trained family physicians for diagnostic, management and documentation errors, potential errors causing serious harm and likelihood of preventability of such errors.

RESULTS

The majority of patient encounters (81%) were with medical assistants. Diagnostic errors were present in 3.6% (95% CI: 2.2, 5.0) of medical records and management errors in 53.2% (95% CI: 46.3, 60.2). For management errors, medication errors were present in 41.1% (95% CI: 35.8, 46.4) of records, investigation errors in 21.7% (95% CI: 16.5, 26.8) and decision making errors in 14.5% (95% CI: 10.8, 18.2). A total of 39.9% (95% CI: 33.1, 46.7) of these errors had the potential to cause serious harm. Problems of documentation including illegible handwriting were found in 98.0% (95% CI: 97.0, 99.1) of records. Nearly all errors (93.5%) detected were considered preventable.

CONCLUSIONS

The occurrence of medical errors was high in primary care clinics particularly with documentation and medication errors. Nearly all were preventable. Remedial intervention addressing completeness of documentation and prescriptions are likely to yield reduction of errors.

Primary care practitioners' views on test result management in EHR-enabled health systems: a national survey

Context

Failure to notify patients of test results is common even when electronic health records (EHRs) are used to report results to practitioners. We sought to understand the broad range of social and technical factors that affect test result management in an integrated EHR-based health system.

Methods

Between June and November 2010, we conducted a cross-sectional, web-based survey of all primary care practitioners (PCPs) within the Department of Veterans Affairs nationwide. Survey development was guided by a socio-technical model describing multiple inter-related dimensions of EHR use.

Findings

Of 5001 PCPs invited, 2590 (51.8%) responded. 55.5% believed that the EHRs did not have convenient features for notifying patients of test results. Over a third (37.9%) reported having staff support needed for notifying patients of test results. Many relied on the patient's next visit to notify them for normal (46.1%) and abnormal results (20.1%). Only 45.7% reported receiving adequate training on using the EHR notification system and 35.1% reported having an assigned contact for technical assistance with the EHR; most received help from colleagues (60.4%). A majority (85.6%) stayed after hours or came in on weekends to address notifications; less than a third reported receiving protected time (30.1%). PCPs strongly endorsed several new features to improve test result management, including better tracking and visualization of result notifications.

Conclusions

Despite an advanced EHR, both social and technical challenges exist in ensuring notification of test results to practitioners and patients. Current EHR technology requires significant improvement in order to avoid similar challenges elsewhere.