Paper Wall: The Law as a Tool of Social Division for Courtroom Officials

The legal system is implicit with biases that shape how it runs on a larger scale, even if its individual members are hesitant about discussing racial, gender, etc. bias

Complications of peripheral arteriography:A new system to identify patients at increased risk

AbstractPurpose: The most quoted literature on arteriographic complications is based on self-reports collected during the mid 1970s. We sought to determine whether those results remain valid despite changes in arteriographic practice and whether patient subgroups at increased risk could be identified.Methods: Five hundred forty-nine consecutive patients were examined after arteriography and twice over 72 hours. Patients were telephoned at least 2 weeks later to identify delayed complications. The sample was divided into two groups to allow independent validation of suspected prognostic factors.Results: The rate of major complications was 2.9% (16/549), but varied from 0.7% to 9.1% among three strata of relative risk. Rates were highest in patients studied for suspected aortic dissection, mesenteric ischemia, gastrointestinal bleeding, or symptomatic carotid artery stenosis and lowest in patients with trauma or aneurysmal disease. Patients studied for claudication or limb-threatening ischemia had intermediate risk (2.0%). Within these strata, congestive heart failure and furosemide use were the only variables independently associated with a significantly increased complication rate.Conclusions: Previous reports have overestimated the risk of arteriography for trauma or aneurysm but substantially underestimate the risk for patients with other common conditions. Such stratified complication rates are essential to understand relative costs and benefits of arteriography and other vascular imaging modalities in specific clinical situations. (J VASC SURG 1995;22:787-94.

Observer performance in Computed Tomography head reporting

Aim: To audit the reporting results of a cohort of radiographers (n=6) completing an accredited academic programme in clinical reporting of Computed Tomography (CT) head examinations. Methods: An audit of retrospective academic image case banks and prospective random clinical workload case banks. Both the academic test banks and clinical workload banks included a wide range of normal and abnormal cases of different levels of difficulty and pathology. Abnormalities included: haemorrhage, fractures, lesions, infarctions, degeneration, and normal variants from a variety of referral sources. True positive and negative, as well as false positive and negative fractions were used to mark the reports, which were analysed for accuracy against a reference standard. Further interobserver variability was assessed using Cohens Kappa, one-way analysis of variance and Tukey for multiple comparisons and significance testing at 95% confidence intervals. Results: The mean accuracy score for all radiographers (n=6) and reports (n=3,008) was 90.7% (95%CI 88.3%-93.0%). Mean sensitivity and specificity rate was 86.9% (95%CI 85.8%-88.2%), and 94% (95%CI 89.6%-98.3%) respectively. The most common errors were associated with herniation, lacunar infarctions and subtle fractures (false negatives) and involutional changes, subtle infarctions, and ventricular dilation (false positives). Conclusions: The results suggest appropriately trained radiographers can successfully undertake to report CT head examinations to a high standard. The adoption of both academic and clinical workload image banks that reflect disease examples and the prevalence that may logically be encountered in practice offers the potential for an accurate measure of performance of radiographer’s abilities

A Case of Intra- and Extra-Mural Hematomas During Recanalization for Chronic Total Occlusion

An intramural hematoma is an accumulation of blood between the internal and external elastic membranes within the medial space, whereas an extramural hematoma is a dilution and/or dissemination of blood throughout the adventitia. Intra- and extra-hematomas are observed by intravascular ultrasound during percutaneous coronary intervention (PCI). The patient described herein presented with angina pectoris. Her coronary angiogram showed diffuse narrowing of the mid-left anterior descending artery and total occlusion of the distal right coronary artery (RCA). Intra- and extra-mural hematomas developed during PCI of the RCA; however, the lesions were covered successfully using long drug-eluting stents

Adult chest radiograph reporting by radiographers: Preliminary data from an in-house audit programme

Aim To examine the adult chest radiograph (CXR) reporting performance of a reporting radiographer in clinical practice using different audit systems; single radiologist and two radiologists, with clinical review of discordant cases. Materials and methods 100 chest radiographs (CXRs) were drawn randomly from a consecutive series of 4800 CXRs which had been reported during a nine month period at a district general hospital by a radiographer after two years of training. Diagnostic outcomes were normal or abnormal, and agreement with the reporting radiographer or not. There was 50% duplication of CXRs reported between three radiologists. Concordance rates were determined for the radiographer-radiologist and inter-radiologist interpretations. Independent clinical review of discordant cases was performed to establish the final diagnosis. Results Ninety-nine cases were reviewed, with 40 cases deemed abnormal by at least one radiologist. Consensus was found with the radiographers report in 59 normal and 33 abnormal CXRs reviewed by two radiologists (96.7% and 86.8% respectively). Seven CXR reports were discrepant with clinical review: mediastinal lymphadenopathy was missed by both radiologist and radiographer; linear atelectasis was reported by two radiologists but not the radiographer. Three cases were over-interpreted and on two occasions at least one radiologist agreed with the radiographer. There was very high concordance between the radiographer and each radiologist, 96%, 96% and 92% respectively. Conclusions This study suggested that regular audit, which incorporates case note review and discrepant reporting within a multidisciplinary setting, should contribute to safe practice

A methodological framework to distinguish spectrum effects from spectrum biases and to assess diagnostic and screening test accuracy for patient populations: Application to the Papanicolaou cervical cancer smear test

<p>Abstract</p> <p>Background</p> <p>A spectrum effect was defined as differences in the sensitivity or specificity of a diagnostic test according to the patient's characteristics or disease features. A spectrum effect can lead to a spectrum bias when subgroup variations in sensitivity or specificity also affect the likelihood ratios and thus post-test probabilities. We propose and illustrate a methodological framework to distinguish spectrum effects from spectrum biases.</p> <p>Methods</p> <p>Data were collected for 1781 women having had a cervical smear test and colposcopy followed by biopsy if abnormalities were detected (the reference standard). Logistic models were constructed to evaluate both the sensitivity and specificity, and the likelihood ratios, of the test and to identify factors independently affecting the test's characteristics.</p> <p>Results</p> <p>For both tests, human papillomavirus test, study setting and age affected sensitivity or specificity of the smear test (spectrum effect), but only human papillomavirus test and study setting modified the likelihood ratios (spectrum bias) for clinical reading, whereas only human papillomavirus test and age modified the likelihood ratios (spectrum bias) for "optimized" interpretation.</p> <p>Conclusion</p> <p>Fitting sensitivity, specificity and likelihood ratios simultaneously allows the identification of covariates that independently affect diagnostic or screening test results and distinguishes spectrum effect from spectrum bias. We recommend this approach for the development of new tests, and for reporting test accuracy for different patient populations.</p