Factors and impact of physicians' diagnostic errors in malpractice claims in Japan

BACKGROUND

Diagnostic errors are prevalent and associated with increased economic burden; however, little is known about their characteristics at the national level in Japan. This study aimed to investigate clinical outcomes and indemnity payment in cases of diagnostic errors using Japan's largest database of national claims.

METHODS

We analyzed characteristics of diagnostic error cases closed between 1961 and 2017, accessed through the national Japanese malpractice claims database. We compared diagnostic error-related claims (DERC) with non-diagnostic error-related claims (non-DERC) in terms of indemnity, clinical outcomes, and factors underlying physicians' diagnostic errors.

RESULTS

All 1,802 malpractice claims were included in the analysis. The median patient age was 33 years (interquartile range = 10-54), and 54.2% were men. Deaths were the most common outcome of claims (939/1747; 53.8%). In total, 709 (39.3%, 95% CI: 37.0%-41.6%) DERC cases were observed. The adjusted total billing amount, acceptance rate, adjusted median claims payments, and proportion of deaths were significantly higher in DERC than non-DERC cases. Departments of internal medicine and surgery were 1.42 and 1.55 times more likely, respectively, to have DERC cases than others. Claims involving the emergency room (adjusted odds ratio [OR] = 5.88) and outpatient office (adjusted OR = 2.87) were more likely to be DERC than other cases. The initial diagnoses most likely to lead to diagnostic error were upper respiratory tract infection, non-bleeding digestive tract disease, and "no abnormality."

CONCLUSIONS

Cases of diagnostic errors produced severe patient outcomes and were associated with high indemnity. These cases were frequently noted in general exam and emergency rooms as well as internal medicine and surgery departments and were initially considered to be common, mild diseases.

Costs analysis of a training intervention for the reduction of preanalytical errors in primary care samples

BACKGROUND

To perform a cost-error analysis based on a quasi-experimental pre-post study of the preanalytical errors in 2 hospital laboratories. The real cost and theoretical cost are defined as the cost resulting from errors with or without the training intervention. The real impact associated to the training program was estimated, calculated as the total associated to the preanalytical errors cost difference. The costs were measured using Andalusian Public Health Service fees. Cost analysis of an educational intervention presented in a previous study from 2017. Preanalytical errors were detected in the laboratories of the University Hospital Virgen de la Victoria (Málaga, Spain) and in the University Hospital Juan Ramón Jiménez (Huelva, Spain).

METHODS

The founded errors were divided into blood and urine samples. Univariate sensitivity analysis was used to assess how parameter uncertainty impacted on overall results. Variations of parameters between 0% and 5% were substituted into the base case.

RESULTS

The real impact associated with educational intervention in LAB1 was an increase of &OV0556;16,961.378, and the expected impact was an increase &OV0556;78,745.27 (difference of &OV0556;61,783.9). In LAB2, the real impact in the same period amounted to &OV0556;260,195.37, and the expected impact was &OV0556;193,905.83 (difference of -&OV0556;66,289.54). The results were different in the 2 laboratories, proving the intervention in only one of them to be more effective.

CONCLUSIONS

Costs analysis determined that this training intervention can provide saves in the costs, as the effectiveness of the educational sessions in reducing preanalytical errors currently results in a significant decrease of the costs associated with these errors.

Is pelvis x-ray essential in stable trauma patients? Step towards lowering the treatment cost

OBJECTIVE

To determine the diagnostic accuracy of clinical examination in detecting pelvic fractures in patients with blunt trauma..

METHODS

The cross-sectional prospective study was conducted at Aga Khan University Hospital, Karachi, from January to June 2015, and comprised alert, awake blunt-trauma patients. Pelvis examination findings were compared to routine pelvic X-rays. SPSS 19 was used for data analysis..

RESULTS

Of the 133 patients, 122 (92%) were males. Overall mean age was 37 ±14.2 years. There were 14 (10%) patients who were true positives with pelvic fracture diagnosis on both clinical examination and pelvic X-ray, while 14 (10%) were false negative on examination. Clinical examination missed 2 patients with evidence of fracture on X-ray and were considered false positive. Besides, 103 (77.4%) patients were true negative as both clinical exam and X-ray showed no evidence of fracture.

CONCLUSION

Omitting pelvic X-ray in the recommended protocol can avoid unnecessary financial burden and reduce undesirable radiation exposure..

The Cost of Not Retesting: Human Immunodeficiency Virus Misdiagnosis in the Antiretroviral Therapy "Test-and-Offer" Era

We compared estimated costs of retesting human immunodeficiency virus (HIV)-positive persons before antiretroviral therapy (ART) initiation to the costs of ART provision to misdiagnosed HIV-negative persons. Savings from averted unnecessary ART costs were greater than retesting costs within 1 year using assumptions representative of HIV testing performance in programmatic settings. Countries should implement re-testing before ART initiation.

The global burden of diagnostic errors in primary care

Diagnosis is one of the most important tasks performed by primary care physicians. The World Health Organization (WHO) recently prioritized patient safety areas in primary care, and included diagnostic errors as a high-priority problem. In addition, a recent report from the Institute of Medicine in the USA, 'Improving Diagnosis in Health Care', concluded that most people will likely experience a diagnostic error in their lifetime. In this narrative review, we discuss the global significance, burden and contributory factors related to diagnostic errors in primary care. We synthesize available literature to discuss the types of presenting symptoms and conditions most commonly affected. We then summarize interventions based on available data and suggest next steps to reduce the global burden of diagnostic errors. Research suggests that we are unlikely to find a 'magic bullet' and confirms the need for a multifaceted approach to understand and address the many systems and cognitive issues involved in diagnostic error. Because errors involve many common conditions and are prevalent across all countries, the WHO's leadership at a global level will be instrumental to address the problem. Based on our review, we recommend that the WHO consider bringing together primary care leaders, practicing frontline clinicians, safety experts, policymakers, the health IT community, medical education and accreditation organizations, researchers from multiple disciplines, patient advocates, and funding bodies among others, to address the many common challenges and opportunities to reduce diagnostic error. This could lead to prioritization of practice changes needed to improve primary care as well as setting research priorities for intervention development to reduce diagnostic error.

An analysis of the most common types of hand injury mistakes and their cost in the acute setting

This study aimed to explore the most common hand injury errors occurring in Emergency Departments in England. A Freedom of Information request was made to the NHS Litigation Authority for claims data related to hand injuries in English Emergency Departments from 2004 to 2014. All successful hand injury claims against an individual DGH ED were also analysed. Two hundred and eighteen successful claims were made, costing a total of £6,273,688.22. Diagnosis error was the most common successful claim (97). Four successful claims were brought against the Emergency Department. Causes of error included the use of inappropriate views and failure to correlate imaging with clinical findings. Hand injury diagnostic error has been the most common cause of successful litigious claims against Emergency Departments over the past 10 years. This paper demonstrates that fracture recognition and clinical diagnosis of hand injuries are key areas to target to reduce error rates.

Cost-effectiveness of noninvasive liver fibrosis tests for treatment decisions in patients with chronic hepatitis B in the UK: systematic review and economic evaluation

We compared the cost-effectiveness of various noninvasive tests (NITs) in patients with chronic hepatitis B and elevated transaminases and/or viral load who would normally undergo liver biopsy to inform treatment decisions. We searched various databases until April 2012. We conducted a systematic review and meta-analysis to calculate the diagnostic accuracy of various NITs using a bivariate random-effects model. We constructed a probabilistic decision analytical model to estimate health care costs and outcomes quality-adjusted-life-years (QALYs) using data from the meta-analysis, literature, and national UK data. We compared the cost-effectiveness of four decision-making strategies: testing with NITs and treating patients with fibrosis stage ≥F2, testing with liver biopsy and treating patients with ≥F2, treat none (watchful waiting) and treat all irrespective of fibrosis. Treating all patients without prior fibrosis assessment had an incremental cost-effectiveness ratio (ICER) of £28,137 per additional QALY gained for HBeAg-negative patients. For HBeAg-positive patients, using Fibroscan was the most cost-effective option with an ICER of £23,345. The base case results remained robust in the majority of sensitivity analyses, but were sensitive to changes in the ≥ F2 prevalence and the benefit of treatment in patients with F0-F1. For HBeAg-negative patients, strategies excluding NITs were the most cost-effective: treating all patients regardless of fibrosis level if the high cost-effectiveness threshold of £30,000 is accepted; watchful waiting if not. For HBeAg-positive patients, using Fibroscan to identify and treat those with ≥F2 was the most cost-effective option.

Colon Capsule Endoscopy for the Detection of Colorectal Polyps: An Economic Analysis

BACKGROUND

Colorectal cancer is a leading cause of mortality and morbidity in Ontario. Most cases of colorectal cancer are preventable through early diagnosis and the removal of precancerous polyps. Colon capsule endoscopy is a non-invasive test for detecting colorectal polyps.

OBJECTIVES

The objectives of this analysis were to evaluate the cost-effectiveness and the impact on the Ontario health budget of implementing colon capsule endoscopy for detecting advanced colorectal polyps among adult patients who have been referred for computed tomographic (CT) colonography.

METHODS

We performed an original cost-effectiveness analysis to assess the additional cost of CT colonography and colon capsule endoscopy resulting from misdiagnoses. We generated diagnostic accuracy data from a clinical evidence-based analysis (reported separately), and we developed a deterministic Markov model to estimate the additional long-term costs and life-years lost due to false-negative results. We then also performed a budget impact analysis using data from Ontario administrative sources. One-year costs were estimated for CT colonography and colon capsule endoscopy (replacing all CT colonography procedures, and replacing only those CT colonography procedures in patients with an incomplete colonoscopy within the previous year). We conducted this analysis from the payer perspective.

RESULTS

Using the point estimates of diagnostic accuracy from the head-to-head study between colon capsule endoscopy and CT colonography, we found the additional cost of false-positive results for colon capsule endoscopy to be $0.41 per patient, while additional false-negatives for the CT colonography arm generated an added cost of $116 per patient, with 0.0096 life-years lost per patient due to cancer. This results in an additional cost of $26,750 per life-year gained for colon capsule endoscopy compared with CT colonography. The total 1-year cost to replace all CT colonography procedures with colon capsule endoscopy in Ontario is about $2.72 million; replacing only those CT colonography procedures in patients with an incomplete colonoscopy in the previous year would cost about $740,600 in the first year.

LIMITATIONS

The difference in accuracy between colon capsule endoscopy and CT colonography was not statistically significant for the detection of advanced adenomas (≥ 10 mm in diameter), according to the head-to-head clinical study from which the diagnostic accuracy was taken. This leads to uncertainty in the economic analysis, with results highly sensitive to changes in diagnostic accuracy.

CONCLUSIONS

The cost-effectiveness of colon capsule endoscopy for use in patients referred for CT colonography is $26,750 per life-year, assuming an increased sensitivity of colon capsule endoscopy. Replacement of CT colonography with colon capsule endoscopy is associated with moderate costs to the health care system.

Measure oriented cost-sensitive SVM for 3D nodule detection

The class imbalance issue occurs when training a computer-aided detection (CAD) system for nodules. This imbalance causes poor prediction performance for true nodules. Moreover, the misclassification costs are different between two classes and high sensitivity of true nodules is essential in the detection. In order to eliminate or reduce the false positives while keeping high sensitivity, we present an effective wrapper framework incorporating the evaluation measure of imbalanced data into the objective function of cost sensitive SVM. We improve the performance of classification by simultaneously optimizing the best pair of misclassification cost parameter, feature subset and intrinsic parameters. We evaluated the method on a 3D Lung nodule dataset, showing that the proposed method outperforms many other exiting common methods, as well as specific imbalanced data learning methods, which indicates the effectiveness of our method on the imbalanced and unequal misclassification cost data classification.

Non-tuberculous mycobacterial infections of veterinary relevance

Mycobacteria play an important role in human and animal health fields. We here examine the place of non tuberculous mycobacteria (NTM) infections in the veterinary context. Relevant aspects of a reference laboratory experience and a literature review are presented in this article. Importance is given both to productivity and to economic losses due to misdiagnosis with bovine tuberculosis and paratuberculosis. The impact NTM may have is relative to geographical location, ecology, husbandry, extent of surveillance programs and bovine tuberculosis and paratuberculosis prevalence. The role of the most relevant NTM in animal disease is summarized with a special focus on Mycobacterium avium subsp. paratuberculosis, given its role as causative agent of paratuberculosis, a disease with huge economic consequences for ruminant livestock.

The consequences of chronic kidney disease mislabeling in living kidney donors

Despite numerous studies that substantiate its long-term safety, barriers to kidney donation persist. These include issues of insurability after donation and its consequent financial and emotional burdens. We present 2 cases in which mislabeling of kidney donors as having chronic kidney disease shortly after kidney donation adversely affected their insurability. A concerted effort should be made to affect public policy such that insurability and the psychosocial well-being of living donors are protected.

Cost-effectiveness of the carbon-13 urea breath test for the detection of Helicobacter pylori: an economic analysis

OBJECTIVES

This analysis aimed to evaluate the cost-effectiveness of various testing strategies for Helicobacter pylori in patients with uninvestigated dyspepsia and to calculate the budgetary impact of these tests for the province of Ontario.

DATA SOURCES

Data on the sensitivity and specificity were obtained from the clinical evidence-based analysis. Resource items were obtained from expert opinion, and costs were applied on the basis of published sources as well as expert opinion.

REVIEW METHODS

A decision analytic model was constructed to compare the costs and outcomes (false-positive results, false-negative results, and misdiagnoses avoided) of the carbon-13 (¹³C) urea breath test (UBT), enzyme-linked immunosorbent assay (ELISA) serology test, and a 2-step strategy of an ELISA serology test and a confirmatory ¹³C UBT based on the sensitivity and specificity of the tests and prevalence estimates.

RESULTS

The 2-step strategy is more costly and more effective than the ELISA serology test and results in $210 per misdiagnosis case avoided. The ¹³C UBT is dominated by the 2-step strategy, i.e., it is more costly and less effective. The budget impact analysis indicates that it will cost $7.9 million more to test a volume of 129,307 patients with the ¹³C UBT than with ELISA serology, and $4.7 million more to test these patients with the 2-step strategy.

LIMITATIONS

The clinical studies that were pooled varied in the technique used to perform the breath test and in reference standards used to make comparisons with the breath test. However, these parameters were varied in a sensitivity analysis. The economic model was designed to consider intermediate outcomes only (i.e., misdiagnosed cases) and was not a complete model with final patient outcomes (e.g., quality-adjusted life years).

CONCLUSIONS

Results indicate that the 2-step strategy could be economically attractive for the testing of H. pylori. However, testing with the 2-step strategy will cost the Ministry of Health and Long-Term Care $4.7 million more than with the ELISA serology test.

Preimplantation genetic diagnosis: a systematic review of litigation in the face of new technology

OBJECTIVE

To study legal cases against IVF facilities pertaining to preimplantation genetic diagnosis (PGD) misdiagnosis.

DESIGN

Systematic case law review.

SETTING

University medical center using US legal databases.

PATIENT(S)

The IVF recipients using PGD services.

INTERVENTION(S)

Lawsuits pertaining to PGD against IVF facilities.

MAIN OUTCOME MEASURE(S)

Lawsuits, court rulings, damage awards, and settlements pertaining to PGD after the birth of a child with a genetic defect.

RESULT(S)

Causes of action pertaining to PGD arise from negligence in performing the procedure as well as failure to properly inform patients of key information, such as inherent errors associated with the PGD process, a facility's minimal experience in performing PGD, and the option of obtaining PGD. Courts have sympathized with the financial burden involved in caring for children with disabilities. Monetary damage awards are based on the costs of caring for children with debilitating defects, including lifetime medical and custodial care.

CONCLUSION(S)

Facilities offering PGD services expose themselves to a new realm of liability in which damage awards can easily exceed the limits of a facility's insurance policy. Competent laboratory personnel and proper informed consent--with particular care to inform patients of the inherent inaccuracies of PGD--are crucial in helping deter liability.

Diagnostic accuracy in patients admitted to hospitals with cellulitis

Misdiagnosis of non-infectious conditions such as cellulitis is a common error and can result in unnecessary hospitalization and antibiotic use. We sought to prospectively determine the misdiagnosis rate of cellulitis among hospitalized patients and to determine if a visually-based computerized diagnostic decision support system (VCDDSS, also named VisualDx) could generate an improved differential diagnosis (DDx) for misdiagnosed patients. In two separate institutions, attending dermatologists or infectious disease specialists evaluated all consecutive patients hospitalized for "cellulitis" by the emergency department. Among 145 subjects enrolled, misdiagnosis occurred in 41 (28%) patients. The diagnosis most commonly mistaken as cellulitis was stasis dermatitis (37%). At one center, in cases that were misdiagnosed by the emergency department, the VCDDSS included the correct diagnosis in the DDx more frequently than the admitting team (18/28 cases (64%) compared to 4/28 cases (14%), p=0.0003). These results demonstrate the capability of this VCDDSS to assist primary care physicians with generating a more accurate DDx when confronted with patients presenting with possible skin infections. Misdiagnoses may result in a significant source of healthcare costs and misdiagnosis-related patient harm. Inclusion of decision support tools early in the diagnostic workflow may reduce misdiagnosis and result in more efficient healthcare management.

Non-melanoma skin cancers in New Zealand--a neglected problem

Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the commonest types of non-melanoma skin cancer (NMSC). The incidence of NMSC has been increasing globally with Australia recording a 1.5-fold increase over the last 17 years. Given that Australia and New Zealand share similar latitude, sun exposure levels, population skin types, and other risk factors, it is conceivable that this increase has also occurred in New Zealand. However, the incidence of NMSC in New Zealand is unknown. The cost of treating NMSC in New Zealand is estimated to be more than NZ$50 million annually, based on extrapolated Australian data. In Australia, NMSC is the most costly burden to its healthcare system, and therefore the Australian Government has allocated resources to improve epidemiological research, and preventative efforts. Currently within New Zealand there is a lack of focus on the NMSC problem. The absence of New Zealand data on the incidence of NMSC has hampered the development of consistent healthcare policies (including preventative measures), that achieve an integrated and sustainable service delivery. A critical analysis of this problem based on longitudinal data is now vitally important to address this neglected problem.

The economic costs of undiagnosed diabetes

The objective is to estimate the national economic costs associated with undiagnosed diabetes mellitus (UDM). UDM is defined as unknowingly having an elevated glucose level that meets the definition of diabetes. National Health and Nutrition Examination Survey (NHANES) data are used to estimate the prevalence of UDM. Because UDM cannot be directly observed in medical claims for analyzing per capita patterns of health care use, we analyze annual medical claims from a proxy population--people within 2 years of first diagnosis of diabetes. For a commercially insured population first diagnosed with diabetes in 2006 (n = 29,770), we compare their annual health care use in 2004 and 2005 to that of patients with no history of diabetes between 2004 and 2006 (n = 3.2 million). We combine estimates of UDM prevalence from NHANES with health care use patterns from the proxy population to estimate etiological fractions that reflect the portion of national health care use associated with UDM. Approximately 6.3 million adults in the United States have UDM in 2007. Annual per capita use of health care services for the UDM proxy population is higher than for a comparable group with no history of diabetes, but lower than for a comparable group with a history of diabetes. The estimated economic costs of UDM in 2007 is $18 billion ($2864 per person with UDM), including medical costs of $11 billion and indirect costs of $7 billion. Although the high prevalence of UDM makes it an important health issue to be studied, data limitations have contributed to a dearth of information on the health care use patterns and economic costs of UDM. By omitting UDM, estimates of the total national cost of diabetes are underestimated.

An examination of economic outcomes associated with misdiagnosis or undertreatment of TIA

Transient ischemic attack (TIA) is a common cerebrovascular event that is associated with a high risk for secondary stroke, possibly higher than stroke itself. Nevertheless, a TIA is often described as a "mini-stroke," implying a less serious event requiring less urgent treatment. In reality, TIA and subsequent secondary stroke are associated with a very high economic burden. Cerebrovascular disease is the most financially costly of all major disease states, while morbidity and mortality risk is highly elevated in TIA patients. TIA is also associated with a very severe quality-of-life burden, which manifests both in terms of diminished functional independence and high rates of depression. Furthermore, TIA is commonly misdiagnosed and underdiagnosed, often leading to inappropriate treatment. More than half of patients who experience TIA are undiagnosed, while those who do receive a diagnosis are often offered neither diagnostic imaging nor hospital admission. Much of the morbidity and mortality associated with TIA and secondary stroke might be avoided by the application of timely and appropriate treatment. Clinical data have shown that accelerated treatment of TIA during its acute phase is associated with an 80% reduction of secondary stroke risk for the following 3 months, the period of greatest risk.

Research malpractice and the issue of incidental findings

Human subject research involving brain imaging is likely to reveal significant incidental findings of abnormal brain morphology. Because of this fact and because of the fiduciary relationship between researcher and subject, board-certified or board-eligible radiologists should review the scans to look for any abnormality, the scans should be conducted in accordance with standard medical practice for reviewing the clinical status of the whole brain, and the informed consent process should disclose the possibility that incidental findings may be revealed and what consequences will follow. In the event such findings are revealed, qualified physicians should explain to the subject the significance of the findings and the alternatives available.

The ECG dilemma: guidelines on improving interpretation

The "ECG Dilemma" was recognized by the American College of Cardiology (ACC) and the American Heart Association more than 10 years ago. Estimates put the number of patients suffering from significant ECG interpretation errors every year in the same range as deaths from diabetes. Missed MI ranks in the top tier of malpractice dollars lost. Guidelines have been put forth to reduce these losses and improve patient safety and quality of care. These guidelines, and suggestions towards implementing them, are discussed.

Role of radiologic imaging at the time of initial diagnosis of stage T1b-T3b melanoma

BACKGROUND

In patients with T1b-T3b cutaneous melanoma the utility of radiologic imaging at the time of diagnosis is unclear. Whether initial imaging led to a change in stage or treatment plan was investigated.

METHODS

The melanoma database was searched for patients with T1b-T3b primary lesions, clinically N0, and asymptomatic for metastatic disease. Radiologic studies conducted before wide local excision +/- sentinel lymph node biopsy as well as all further imaging and investigations were analyzed. Outcome measures included upstaging, change in initial surgical management, true-positive, false-positive, true-negative, and false-negative rates of each imaging modality.

RESULTS

In all, 344 preoperative imaging studies (chest x-ray [CXR], computed tomography [CT], positron emission tomography [PET]/CT) were performed on 158 patients, resulting in 49 findings suspicious for metastatic melanoma and 134 findings suggestive of nonmelanoma pathology. Only 1 of 344 (0.3%) studies, a PET/CT, correlated with confirmed metastatic melanoma. The false-positive rates were CXR 5 of 7 (71.4%), chest CT 21 of 24 (87.5%), abdomen/pelvis CT 10 of 11 (90.9%), head CT 2 of 2 (100.0%), PET/CT 3 of 5 (60.0%). No patient was upstaged or had a change in initial surgical management based on preoperative imaging. The cost of all initial imaging and imaging to follow-up abnormal findings was estimated as $555,308 for the 158 patients studied.

CONCLUSIONS

Imaging at the time of initial diagnosis of T1b-T3b, clinically N0, M0 melanoma was of low yield with a high false-positive rate, and did not lead to upstaging or change in initial surgical management. These findings suggest that imaging of asymptomatic patients at the time of diagnosis may not be warranted.

Medical errors arising from outsourcing laboratory and radiology services

OBJECTIVE

Document errors and the nuisance factor inherent in the informational exchange that occurs with the outsourcing of laboratory and radiology examinations.

METHODS

Three infectious diseases physicians at a tertiary care hospital recorded problems involving data transmitted by telephone or fax from outsource providers for 4 months. This included in- and outpatients, and those in transition from one status to another.

RESULTS

Outsourcing laboratory and radiology examinations of insured outpatients is a common practice. Insurance companies determine which healthcare facility performs these tests based on contractual agreements with outsource providers. This leads to confusion and frustration for the doctor and patient alike, and occasionally, to medical error.

CONCLUSIONS

The exchange of patient data involved in outsourcing is subject to systemic errors that do not allow of easy solution.

Detecting Occult Malignancy in Prophylactic Mastectomy: Preoperative MRI Versus Sentinel Lymph Node Biopsy

BACKGROUND

High-risk patients undergoing prophylactic mastectomy (PM) may have unsuspected cancers identified on pathology. The optimum way to identify and manage them is controversial. Magnetic resonance imaging (MRI) may identify occult cancer preoperatively. Sentinel lymph node biopsy (SLNB) allows intraoperative staging and axillary dissection during the same operation. We determined the efficacy and cost of MRI and/or SLNB in managing high-risk PM patients.

METHODS

We reviewed 192 PMs in 173 patients from 1999 to 2005. Costs were estimated for MRI and SLNB during PM by the 2005 Medicare Resource-Based Relative Value Scale. We also estimated costs and procedures for the four strategies in a larger hypothetical cohort.

RESULTS

A total of 19 (10%) of 192 PMs contained occult cancers, 14 ductal carcinoma-in-situ (DCIS) and 5 invasive ductal carcinoma (IDC). In 59 patients, MRI detected an IDC but missed two DCIS and an IDC. Positive MRIs generated an additional average cost of $1,207 per patient. In 56 PMs with SLNB, 6 occult cancers were found, 5 DCIS and 1 IDC, all with negative SLNBs. Adding a SLNB costs an additional average of $644. A theoretical analysis demonstrated that PM alone costs $808 per patient, PM with SLNB costs $1,420, PM with MRI and selective SLNB costs $1,774, and PM with routine MRI and SLNB costs $2,379.

CONCLUSIONS

MRI adds great cost and misses most occult cancers in PMs. SLNB allows the rare patient with occult IDC to avoid axillary dissection but adds cost. Given the low rate of unsuspected invasive cancers and the costs of MRI and SLNB, neither is recommended as standard practice for PM patients.

LITIGATION OF MISSED CERVICAL SPINE INJURIES IN PATIENTS PRESENTING WITH BLUNT TRAUMATIC INJURY

BACKGROUND

Approximately 800,000 cervical spines are cleared in emergency departments each year. Errors in diagnosis of cervical spine injury are a potentially huge medicolegal liability, but no established protocol for clearance of the cervical spine is known to reduce errors or delays in diagnosis.

METHODS

The Lexis-Nexis, Westlaw, and Medline databases were queried for cases of missed cervical injury. Errors were categorized according to a novel system of classification. Type I errors occurred when inadequate or improper tests were ordered. Type II errors occurred when adequate tests were ordered, but were either misread or not read. Type III errors occurred when adequate tests were ordered and read accurately, but the ordered test was not sensitive enough to detect the injury.

RESULTS

Twenty cases of missed or delayed diagnosis of cervical spine injury were found in 10 jurisdictions. Awards averaged $2.9 million (inflation adjusted to 2002 dollars). Eight cases resulted in verdicts in favor of the defendant, but none of these cases involved an alleged Type II error.

CONCLUSION

Fear of lawsuits encourages defensive medicine and complicates the process of clearing a patient's cervical spine. This analysis adds medicolegal support for the judicious use of imaging studies in current cervical spine clearance protocols. However, exposure to significant liability suggests that a low threshold for computed tomography is a reasonable alternative.

The impact of unrecognized bipolar disorders among patients treated for depression with antidepressants in the fee-for-services California Medicaid (Medi-Cal) program: a 6-year retrospective analysis

INTRODUCTION

The cost of unrecognized bipolar disorders over time is unknown.

METHODS

Ten years of data from the California Medicaid program were used to identify depressed patients initiating new episodes of antidepressant therapy and with 6+ years of post-treatment data. Recognized bipolar (RBP) patients received a BP diagnosis or used mood stabilizers in the pre-index period. Unrecognized bipolar (UBP) patients received an initial BP diagnosis or used a mood stabilizer in the post-index period. Depression-only (MDD) patients had no BP diagnosis or mood stabilizer use. Three analyses were conducted: (1) regression models of cost per year, (2) a regression model of aggregate cost over 6 years and (3) a time trend analysis of the costs for UBP patients.

RESULTS

14,809 patients were identified: RBP 14.5%, UBP 28.2% and MDD 57.3%. The growth in costs per month for UBP patients over 6 years (171%) far exceeds the growth for RBP and MDD patients (82% and 95%, respectively). RBP and MDD patients cost 2316 dollars and 1681 dollars less per year in the 6th year relative to UBP patients (p<0.0001 for both estimates). The cost per month increased by 91 dollars for each month of delayed diagnosis (p=0.011). Costs for UBP patients increased by 10 dollars per month prior to their initial BP diagnosis (p<0.001) and by -1.01 dollars thereafter (p=0.006 for the change in slope).

LIMITATIONS

Classification of patients based on diagnosis or mood stabilizer use using paid claims data is inexact.

CONCLUSIONS

Early diagnosis of bipolar disorders may significantly reduce health care cost.

The costs of epilepsy misdiagnosis in England and Wales

BACKGROUND

The management of epilepsy incurs significant costs to the United Kingdom (UK) National Health Service (NHS). Making a diagnosis of epilepsy can, however, be difficult and misdiagnosis frequently occurs when patients are seen by non-specialists. This study estimates the financial costs of epilepsy misdiagnosis in the NHS in England and Wales.

METHODS

Standard costing methods were applied to estimate the costs attributable to epilepsy misdiagnosis. The primary data were published in UK studies on the prevalence of epilepsy, epilepsy misdiagnosis and costs identified from Medline, Cinahl and Embase (1996-May 2006).

RESULTS

An estimated total of 92,000 people were misdiagnosed with epilepsy in England and Wales in 2002. The average medical cost per patient per year of misdiagnosis was 316 pounds sterling, with the chief economic burdens being inpatient admissions (45%), inappropriate prescribing of antiepileptic drugs (AEDs) (26%), outpatient attendances (16%) and general practitioner (GP) care (8%). The estimated annual medical costs in England and Wales were 29,000,000 pounds sterling, while total costs could reach up to 138,000,000 pounds sterling a year.

CONCLUSIONS

Allowing for uncertainty, and considering the analysis exclusively from the NHS/CBS (community based services) perspective the opportunity costs of misdiagnosis are substantial. There is a need for health care commissioners to ensure that misdiagnosis is kept to a minimum by ensuring that individuals with a recent onset suspected seizure are seen as soon as possible by a specialist medical practitioner with training and expertise in epilepsy.

The financial and clinical implications of adult malaria diagnosis using microscopy in Kenya

OBJECTIVE

A recent observational study undertaken at 17 health facilities with microscopy in Kenya revealed that potential benefits of malaria microscopy are not realized because of irrational clinical practices and the low accuracy of routine microscopy. Using these data, we modelled financial and clinical implications of revised clinical practices and improved accuracy of malaria microscopy among adult outpatients under the artemether-lumefantrine (AL) treatment policy for uncomplicated malaria in Kenya.

METHODS

The cost of AL, antibiotics and malaria microscopy and the expected number of malaria diagnosis errors were estimated per 1,000 adult outpatients presenting at a facility with microscopy under three scenarios: (1) current clinical practice and accuracy of microscopy (option A), (2) revised clinical practice with current accuracy of microscopy (option B) and (3) revised clinical practice with improved accuracy of microscopy (option C). Revised clinical practice was defined as performing a blood slide for all febrile adults and prescribing antimalarial treatment only for positive results. Improved accuracy of routine microscopy was defined as 90% sensitivity and specificity. In the sensitivity analysis, the implications of changes in the cost of drugs and malaria microscopy and changes in background malaria prevalence were examined for each option.

RESULTS

The costs of AL, antibiotics and malaria microscopy decreased from 2,154 dollars under option A to 1,254 dollars under option B and 892 dollars under option C. Of the cost savings from option C, 72% was from changes in clinical practice, while 28% was from improvements in the accuracy of microscopy. Compared with 638 malaria overdiagnosis errors per 1,000 adults under option A, 375 and 548 fewer overdiagnosis errors were estimated, respectively, under options B and C. At the same time, the number of missed malaria diagnoses remained generally low under all options. Sensitivity analysis showed that both options B and C are robust to a wide range of assumptions on the costs of drugs, costs of blood slides and malaria prevalence.

CONCLUSIONS

Even with the imperfect microscopy conditions at Kenyan facilities, implementation of revised clinical practice (option B) would substantially reduce the costs and errors from malaria overdiagnosis. Additional interventions to improve the accuracy of microscopy (option C) can achieve further benefits; however, improved microscopy in the absence of revised clinical practice is unlikely to generate significant cost savings. Revision of guidelines to state explicitly age-specific indications for the use and interpretation of malaria microscopy is urgently needed. Further prospective studies are required to evaluate the effectiveness and costs of interventions to improve clinical practice and the accuracy of malaria microscopy.

Delayed recognition of a pseudo-outbreak of Mycobacterium terrae

Pseudo-outbreaks of mycobacteria are difficult to recognize because of long incubation periods for growth and species identification. We report our experience with one clinical microbiology laboratory that isolated a species of nontuberculous mycobacteria from 14 patient specimens. These specimens came from 12 patients at 2 hospitals over a 6-day period and included 6 different fluids or tissues. Because of the delay between mycobacterial specimen submission and growth in culture, the outbreak was not noted until more than a month later. Initial species determination by a reference laboratory indicated that these isolates were Mycobacterium fortuitum. One patient received treatment for presumed M fortuitum brain infection, and it was not effective in changing her clinical course. The isolates were sent to the Centers for Disease Control and Prevention (CDC) for identification and typing by pulsed-field gel electrophoresis. The CDC determined that the isolates were an identical strain of M terrae, thus confirming a pseudo-outbreak. Combining pseudo-outbreak isolates with those correctly identified initially as M terrae during the 6-day period in question, there were 22 samples from 20 patients with M terrae. Since the pseudo-outbreak, the number of cultures of M terrae in the clinical laboratory has returned to baseline levels without any specific intervention.

Value of quantitative D-dimer assays in identifying pulmonary embolism: implications from a sequential decision model

OBJECTIVES

To examine the cost-effectiveness of a quantitative D-dimer assay for the evaluation of patients with suspected pulmonary embolism (PE) in an urban emergency department (ED).

METHODS

The authors analyzed different diagnostic strategies over pretest risk categories on the basis of Wells criteria by using the performance profile of the ELISA D-dimer assay (over five cutoff values) and imaging strategies used in the ED for PE: compression ultrasound (CUS), ventilation-perfusion (VQ) scan (over three cutoff values), CUS with VQ (over three cutoff values), computed tomography (CT) angiogram (CTA) with pulmonary portion (CTP) and lower-extremity venous portion, and CUS with CTP. Data used in the analysis were based on literature review. Incremental costs and quality-adjusted-life-years were the outcomes measured.

RESULTS

Computed tomography angiogram with pulmonary portion and lower-extremity venous portion without D-dimer was the preferred strategy. CUS-VQ scanning always was dominated by CT-based strategies. When CTA was infeasible, the dominant strategy was D-dimer with CUS-VQ in moderate- and high-Wells patients and was D-dimer with CUS for low-Wells patients. When CTP specificity falls below 80%, or if its overall performance is markedly degraded, preferred strategies include D-dimer testing. Sensitivity analyses suggest that pessimistic assessments of CTP accuracy alter the results only at extremes of parameter settings.

CONCLUSIONS

In patients in whom PE is suspected, when CTA is available, even the most sensitive quantitative D-dimer assay is not likely to be cost-effective. When CTA is not available or if its performance is markedly degraded, use of the D-dimer assay has value in combination with CUS and a pulmonary imaging study. These conclusions may not hold for the larger domain of patients presenting to the ED with chest pain or shortness of breath in whom PE is one of many competing diagnoses.

Pseudo-Latex Allergy Associated With ???Latex??? Paint Exposure: A Potential Cause of Iatrogenic Disability

OBJECTIVE

We sought to describe outcomes for three health care workers with natural rubber latex (NRL) allergy reporting illness after exposure to latex paint.

METHODS

We undertook a retrospective review of medical and occupational histories, diagnostic, treatment, and work recommendations. Outcomes included lost time, workers compensation indemnity costs, and return to work.

RESULTS

None of the paints contained NRL. Cases 1 and 2 initially were misdiagnosed as suffering allergic reactions to NRL, resulting in 7 and 23 months lost time, $15,790 and $139,000 indemnity costs, respectively, and both failing to return to work. Case 3 was correctly diagnosed as not exposed to NRL, with only several lost days, no indemnity costs, and continued to work.

CONCLUSIONS

The failure to recognize that synthetic paints do not contain NRL can lead to misdiagnosis, inappropriate exposure, and work avoidance recommendations and iatrogenic disability.

Applying Taguchi methods to health care

PURPOSE

The aim of this article is to show how Taguchi methods can be applied to health care.

DESIGN/METHODOLOGY/APPROACH

The quadratic loss function is at the heart of Taguchi methods. It is a powerful motivator for a quality strategy and can be used to adequately model the loss to society in health care. It also establishes a relationship between cost and variability. Therefore, it can be integrated with the performance and parameters of the design of medical applications. Signal-to-noise ratios give a sense of how close is the performance to the ideal. By maximizing the signal-to-noise ratio, quality-engineering activities can be aimed at identifying near-optimum levels of factors and making quality equal to zero.

FINDINGS

This article shows that, when the patients' requirements are consistently met, lower losses can provide an impetus to improve patient satisfaction.

ORIGINALITY/VALUE

The article outlines areas in health care where Taguchi methods can easily be applied.

Cervical spine evaluation in urban trauma centers: Lowering institutional costs and complications through helical CT scan1

BACKGROUND

In the evaluation of the cervical spine (c-spine), helical CT scan has higher sensitivity and specificity than plain radiographs in the moderate- and high-risk trauma population, but is more costly. We hypothesize that institutional costs associated with missed injuries make helical CT scan the least costly approach.

STUDY DESIGN

A cost-minimization study was performed using decision analysis examining helical CT scan versus radiographic evaluation of the c-spine. Parameter estimates were obtained from the literature for probability of c-spine injury, probability of paralysis after missed injury, plain film sensitivity and specificity, CT scan sensitivity and specificity, and settlement cost of missed injuries resulting in paralysis. Institutional costs of CT scan and plain radiography were used. Sensitivity analyses tested robustness of strategy preference, accounted for parameter variability, and determined threshold values for individual parameters on strategy preference.

RESULTS

C-spine evaluation with helical CT scan has an expected cost of US 554 dollars per patient compared with US 2,142 dollars for plain films. CT scan is the least costly alternative if threshold values exceed US 58,180 dollars for institutional settlement costs, 0.9% for probability of c-spine fracture, and 1.7% for probability of paralysis. Plain films are least costly if CT scan costs surpass US 1,918 dollars or plain film sensitivity exceeds 90%.

CONCLUSIONS

Helical CT scan is the preferred initial screening test for detection of cervical spine fractures among moderate- to high-risk patients seen in urban trauma centers, reducing the incidence of paralysis resulting from false-negative imaging studies and institutional costs, when settlement costs are taken into account.

A cost-effectiveness analysis of four management strategies in the determination and follow-up of atypical squamous cells of undetermined significance

Atypical squamous cells of undetermined significance (ASC-US) are the most common abnormal cytological result on Papanicolaou (Pap) smear. We analyzed four management strategies in a hypothetical cohort of women divided by age group: (1) immediate colposcopy, (2) repeat cytology after an ASC-US Pap smear result, (3) conventional Pap with reflex human papillomavirus (HPV) testing, and (4) liquid-based cytology with reflex HPV testing. Parameter variables were collected from previously published data. Strategies that included reflex HPV testing had the lowest overall costs for all age groups combined. Repeat Pap smears had the highest number of true positive results throughout all stages but also had the uppermost number of missed cancers and highest costs. Immediate colposcopy had the second highest overall costs and detected fewer true positive results than liquid-based cytology. Younger women (aged 18-24 yr) consistently had higher total costs for all strategies investigated. Using the incremental cost-effectiveness (CE) ratio, the immediate colposcopy strategy was more costly and less effective than liquid-based cytology and, therefore, was dominated. The incremental CE ratio was lowest for liquid-based cytology compared with conventional cytology and liquid-based cytology with reflex HPV testing was the most cost-effective strategy.

The role of the clinical immunology laboratory in the diagnosis and monitoring of connective tissue diseases

Connective tissue diseases (CTD) are a group of autoimmune systemic diseases that can affect any organ-system in the body. The initial clinical presentations of these diseases overlap, not only with each other, but also with a wide range of other rheumatological and non-rheumatological disorders. Due to these reasons, clinicians depend heavily on the use of the clinical immunology laboratory for the diagnosis of CTD. A large number of tests exist in the laboratory for the investigation of CTD and each test can be performed by a number of different methods, each with its own limitations. Consequently, the significance of the results generated not only has to be interpreted in relation to the clinical picture, but also to the method used to generate the results. Moreover, within the laboratory, there is a hierarchical testing system for the investigation of CTD and if this system is used appropriately, in conjunction with the clinical picture, can result in the diagnosis/exclusion of CTD more efficiently and economically. In contrast, random use of the laboratory tests, combined with limited knowledge of the methods used to carry out these tests, can lead to delay or even misdiagnosis, as well as can lead to wastage of resources. In the following review, we have discussed the various tests that are used in the investigation of CTD, as well as the different methods used to carry out these tests, with the hope that such knowledge would lead to a more efficient and economical use of the clinical immunology laboratory in the investigation of CTD.