The relationship of clinical and academic productivity in a university hospital radiology department

OBJECTIVE

The purpose of this study was to evaluate the relationship between clinical and academic productivity over a 2-year period in a university hospital radiology department.

MATERIALS AND METHODS

Clinical productivity, as determined by the number of total professional relative value units generated, was compared with academic productivity, which was determined by the number of published peer-reviewed articles, published non-peer-reviewed articles, published abstracts, and presentations delivered by each full-time clinical faculty member. The relationships of age, academic rank, administrative position, and division within the department were also assessed for their effect on relative value units and academic productivity.

RESULTS

We found a significant inverse relationship between relative value units and the number of published peer-reviewed articles, published abstracts, and presentations. Age, academic rank, and administrative responsibilities had no effect on the number of relative value units. Faculty in the neuroradiology and cardiovascular-interventional radiology divisions generated more relative value units than did other faculty members.

CONCLUSION

Faculty members with higher levels of clinical productivity showed significantly lower levels of academic productivity. This finding is consistent with the idea that increases in the clinical workload may diminish research output.

I.v. devices and related infections: causes and complications

The use of intravenous devices has long been established as a life-saving and important part of total patient management. However, such devices are not without risk and their use is frequently complicated by local or systemic infections and complications. Twenty-five million patients are estimated to enter the NHS annually and receive some form of intravenous therapy by the peripheral route (Campbell, 1998). It behoves all staff who are involved in the management of intravenous devices to base their practice on what is agreed by consensus in the literature as being effective in reducing the risk of hospital-acquired infections. This article draws together such literature and presents recommendations for good practice for the management of intravenous-related devices.

Size of colorectal liver metastases at abdominal CT: comparison of precontrast and postcontrast studies

PURPOSE

To investigate whether measurements of hepatic metastases from colorectal carcinoma before contrast material administration are significantly different statistically from measurements after contrast material administration.

MATERIALS AND METHODS

Twenty-four patients with hepatic metastases from colorectal carcinoma underwent spiral computed tomography (CT) with 7-mm collimation. The liver was imaged before and in the portal-dominant phase after intravenous contrast material administration. For each scan, one to three discrete liver lesions were selected for measurement (n = 49). Three experienced radiologists performed independent measurements of the selected lesions on both pre- and postcontrast images at a computer workstation. A three-way analysis of variance (ANOVA) was performed: subjects by raters (the three independent radiologists) by pre- or postcontrast status. The dependent variable was the product of bidimensional measurements.

RESULTS

Sixty-seven percent (33 of 49) of the lesions were measured as larger on precontrast images; 33% (16 of 49), as smaller. There was high interrater reliability, with an intraclass correlation coefficient greater than 0.9 ANOVA showed significant subject, rater, and contrast material effects (P < .001) for the largest lesions in each liver. Contrast material status was a significant factor for all lesion sizes (P < .003).

CONCLUSION

On average, hepatic metastases from colorectal carcinoma are significantly smaller after contrast material administration.

Stillbirths among offspring of male radiation workers at Sellafield nuclear reprocessing plant

BACKGROUND

Ionising radiation is a known mutagen, but few studies have examined transgenerational effects of paternal exposure in human beings. The workforce at the Sellafield nuclear reprocessing plant in the county of Cumbria, UK, is the most highly exposed workforce in western Europe and North America. This study, which is part of a larger programme of work investigating the health of the children of the Sellafield workforce, set out to find whether there was evidence of an association between stillbirth risk and paternal exposure to ionising radiation.

METHODS

We collected details from birth registration documents for all singleton 248,097 livebirths and 3715 stillbirths in the county of Cumbria 1950-89. Within this cohort the 130 stillbirths and 9078 livebirths to partners of male radiation workers employed at Sellafield were identified. Logistic regression was used to analyse the relation between stillbirth risk and father's preconceptional radiation exposure, with adjustment for social class, year of birth, father's age, and birth order.

FINDINGS

A significant positive association was found between the risk of a baby being stillborn and the father's total exposure to external ionising radiation before conception (adjusted odds ratio per 100 mSv 1.24 [95% CI 1.04-1.45], p=0.009). The risk was higher for stillbirths with congenital anomaly and was highest for the nine stillbirths with neural-tube defects. The statistical models predicted that, were the association to be interpreted as causal, between 0 and 31.9 of the 130 stillbirths to the workforce may be attributable to father's radiation exposure.

INTERPRETATION

The findings of an increased risk of stillbirth with increasing paternal occupational exposure to external radiation are qualitatively consistent with those from animal models, though the risk estimate is higher. Although we cannot exclude the possibility of an unmeasured risk factor for stillbirth, confounded with paternal preconceptional irradiation, extensive checks confirmed that the statistical models were a good fit to the data and there was not statistical evidence of unmeasured factors.

Do interventional radiologists pose a significant threat to the practice of vascular surgery?

PURPOSE

Vascular surgeons have become concerned recently about perceived threats to their practices posed by the growth of interventional radiology. The authors studied nationwide 1996 Medicare Part B procedure data to determine the seriousness of these threats.

MATERIALS AND METHODS

The national Health Care Financing Administration (HCFA) Physician/Supplier Procedure Summary Master File for 1996 was searched. Two hundred thirteen distinct Current Procedural Terminology (CPT-4) codes were identified for therapeutic surgical and percutaneous interventional procedures performed to treat noncardiac vascular diseases. For each code, determination was made of total volume, specialty of the physician providers, and Medicare Part B reimbursement dollars paid to the providers as professional fees. In view of the conflicts among various specialties over peripheral vascular interventions, the authors also determined the percentages of these procedures performed by radiologists, surgeons, cardiologists, and other physicians.

RESULTS

A total of 759,548 noncardiac therapeutic vascular procedures (operations or percutaneous interventions) were performed during 1996 in patients receiving Medicare benefits. Radiologists performed 135,103 (17.8%) of these procedures but received only 10.4% of professional reimbursements. By contrast, surgeons performed 510,871 (67.3%) procedures, but received 78.0% of professional reimbursements. Cardiologists performed 4.7% of procedures and other specialists performed the remaining 10.3%. Radiologists performed 75.5% of percutaneous transluminal angioplasties, the majority of thrombolysis procedures, stent placements, and portal decompression procedures, and approximately half of inferior vena cava interruptions. Cardiologists performed 12.6% of percutaneous transluminal angioplasties, surgeons performed 6.3%, and other specialists performed 5.6%.

CONCLUSIONS

In terms of overall physician workload and professional reimbursements paid for invasive treatment of all types of noncardiac vascular disease, surgeons predominate and do not appear to be seriously threatened by interventional radiologists. Radiologists perform three-fourths of noncardiac percutaneous transluminal angioplasties and a majority of other percutaneous interventional therapies for vascular disease, but some inroads have been made by cardiologists and surgeons, particularly the former.

Quantifying the effect of population mixing on childhood leukaemia risk: the Seascale cluster

A statistical model was developed based on Poisson regression of incidence of childhood leukaemia and non-Hodgkin's lymphoma (NHL) in relation to population mixing among all 119 539 children born 1969-1989 to mothers living in Cumbria, north-west England, (excluding Seascale). This model was used to predict the number of cases in Seascale (the village adjacent to the Sellafield nuclear installation) children, born 1950-1989 and diagnosed before 1993. After allowing for age, the incidence of acute lymphoblastic leukaemia (ALL) and NHL was significantly higher among children born in areas with the highest levels of population mixing, relative risk (RR) = 11.7 (95% confidence interval (CI) 3.2-43) and was highest among children of incomers. The model predicted up to 3.0 (95% CI 1.3-6.0) cases of ALL/NHL in children born in Seascale compared to six observed and 2.0 (95% CI 1.0-3.4) cases in children resident, but not born, in Seascale compared to two observed. Population mixing is a significant risk factor for ALL/NHL, especially in young children, accounting for over 50% of cases in Cumbria and most cases in Seascale.

Cell-autonomous and non-autonomous requirements for the zebrafish gene cloche in hematopoiesis

Vertebrate embryonic hematopoiesis is a complex process that involves a number of cellular interactions, notably those occurring between endothelial and blood cells. The zebrafish cloche mutation affects both the hematopoietic and endothelial lineages from an early stage (Stainier, D. Y. R., Weinstein, B. M., Detrich, H. W. R., Zon, L. I. and Fishman, M. C. (1995) Development 121, 3141–3150). cloche mutants lack endocardium, as well as head and trunk endothelium, and nearly all blood cells. Cell transplantation studies have revealed that the endocardial defect in cloche is cell-autonomous: wild-type cells can form endocardium in mutant hosts, but mutant cells never contribute to the endocardium in wild-type or mutant hosts. In this paper, we analyze the cell-autonomy of the blood defect in cloche. The blood cell deficiency in cloche mutants could be an indirect effect of the endothelial defects. Alternatively, cloche could be required cell-autonomously in the blood cells themselves. To distinguish between these possibilities, we cotransplanted wild-type and mutant cells into a single wild-type host in order to compare their respective hematopoietic capacity. We found that transplanted wild-type cells were much more likely than mutant cells to contribute to circulating blood in a wild-type host. Furthermore, in the few cases where both wild-type and mutant donors contributed to blood in a wild-type host, the number of blood cells derived from the wild-type donor was always much greater than the number of blood cells derived from the mutant donor. These data indicate that cloche is required cell-autonomously in blood cells for their differentiation and/or proliferation. When we assessed early expression of the erythropoietic gene gata-1 in transplant recipients, we found that mutant blastomeres were as likely as wild-type blastomeres to give rise to gata-1-expressing cells in a wild-type host. Together, these two sets of data argue that cloche is not required cell-autonomously for the differentiation of red blood cells, as assayed by gata-1 expression, but rather for their proliferation and/or survival, as assayed by their contribution to circulating blood. In addition, we found that transplanted wild-type cells were less likely to express gata-1 in a mutant environment than in a wild-type one, suggesting that cloche also acts non-autonomously in red blood cell differentiation. This non-autonomous function of cloche in red blood cell differentiation may reflect its cell-autonomous requirement in the endothelial lineage. Thus, cloche appears to be required in erythropoiesis cell non-autonomously at a step prior to gata-1 expression, and cell-autonomously subsequently.

Stillbirths in relation to the coastline of Cumbria, 1950-89

The nuclear installation at Sellafield, in west Cumbria in the north of England, has discharged radioactive waste into the Irish Sea since 1952. The objective of this paper was to investigate whether women living near to the coast in Cumbria had an increased risk of having stillborn children. A retrospective cohort analysis was carried out using all 259,050 births (4017 stillbirths) to women normally resident in Cumbria during 1950-89, allowing for year of birth, social class and birth order using (i) comparison of observed and expected numbers of stillbirths in distance bands relative to the coast, (ii) comparison of cumulative observed and expected numbers of stillbirths by distance from the coast, and (iii) logistic regression analysis of stillbirth risk in relation to distance from the coast. Comparison of observed and expected numbers of stillbirths in distance bands within 10 km of the coast did not provide evidence of an excess risk of stillbirth closer to the coast. The comparison of the cumulative observed and expected numbers of stillbirths within 10 km of the coast supported this result. Logistic regression analysis of all births in Cumbria showed that distance from the coast did not significantly influence stillbirth risk (P > 0.05). There was no evidence to suggest an increased risk of stillbirth in mothers resident nearer to the coast.

Repeat tear of postoperative meniscus: potential MR imaging signs

PURPOSE

To determine the usefulness of five magnetic resonance (MR) signs of repeat tears of the postoperative meniscus.

MATERIALS AND METHODS

Fat-saturated proton-density-weighted and T2-weighted MR images in 20 patients who had undergone at least two knee surgeries were reviewed. Second-look arthroscopic confirmation of meniscal status was available in all patients. MR images of 39 menisci (10 repeat tears, 11 postoperative menisci without repeat tears, three tears in previously normal menisci, and 15 normal menisci) were evaluated for (a) a linear area of abnormal signal intensity extending to an articular surface on intermediate-weighted images, (b) abnormal meniscal morphology, (c) likelihood of a typical postoperative appearance, (d) fluid extending into the linear area on T2-weighted images, and (e) cartilage defects. Two radiologists rated their confidence on a five-point scale for the presence of these signs and were compared for level of agreement.

RESULTS

The intraclass correlation coefficient (range, 0.75-0.91) indicated a high level of agreement. Areas under the receiver operating characteristic curves were large (range, 0.70-0.87) for all five signs, with a line (grade 3 signal intensity) and fluid within a line having the highest areas. These two signs also had the highest statistical scores (chi 2 = 14.12 and 13.30; P < .002; odds ratio, 1.588 and 1.599 for the line and the fluid within the line, respectively).

CONCLUSION

The two best MR signs of repeat tear of the postoperative meniscus were the presence of a line and fluid within the line extending to an articular surface.

Increased soft-tissue blood flow in patients with reflex sympathetic dystrophy of the lower extremity revealed by power Doppler sonography

OBJECTIVE

We evaluated the ability of power Doppler sonography to show increased soft-tissue blood flow in patients with reflex sympathetic dystrophy of the lower extremity.

SUBJECTS AND METHODS

Power Doppler sonography was performed in 30 patients with reflex sympathetic dystrophy of the lower extremity and in 26 asymptomatic control subjects. The bilateral power Doppler sonograms that were obtained of the soft tissues of the dorsum of the foot of each subject were grouped in pairs, and three sonologists who were unaware of clinical information independently reviewed the images. Images were evaluated for the amount of power Doppler signal shown on the following scale: 1 = no flow or minimal flow; 2 = mild flow; 3 = moderate flow; and 4 = marked flow.

RESULTS

More power Doppler flow was seen in the patients with reflex sympathetic dystrophy than in the control subjects (p < .005). In addition, side-to-side asymmetry of flow was seen in patients, but this trend was not statistically significant (p < .20). Receiver operating characteristic (ROC) analysis showed that combined flow and asymmetry were more related to reflex sympathetic dystrophy than either parameter alone (area under the ROC curve: for flow, 0.748; for asymmetry, 0.566; for both, 0.799). We found that when the sum of power Doppler flow in both feet was greater than or equal to five, and asymmetry of flow was greater than or equal to one, the sensitivity of power Doppler sonography for reflex sympathetic dystrophy was 73% and the specificity was 92%.

CONCLUSION

Patients with reflex sympathetic dystrophy of the lower extremity have increased power Doppler flow compared with asymptomatic control subjects. Patients may also exhibit more side-to-side asymmetry of flow than control subjects.

Moving beyond content validation of nursing diagnoses

TOPIC

Studies to establish construct and criterion-related validity of nursing diagnoses.

PURPOSE

The overwhelming majority of previous studies addressed content validation by nurse experts. This paper describes strategies to move beyond content validation research to construct and criterion-related validation.

SOURCES

The range of studies that should be conducted for development of nursing diagnoses are reviewed with examples drawn from the field of psychology. Existing studies on the diagnoses of ineffective breathing pattern, ineffective airway clearance and impaired gas exchange are used as examples.

CONCLUSIONS

Many types of studies are needed for each nursing diagnosis. Increased funding and support for nursing diagnosis research will be facilitated by attention to the accuracy of nurses' diagnoses and outcomes of the diagnostic process.

Neuroblastoma in Europe: differences in the pattern of disease in the UK. SENSE. Study group for the Evaluation of Neuroblastoma Screening in Europe

BACKGROUND

Neuroblastoma is a major contributor to childhood cancer mortality, but its prognosis varies with age and stage of disease, and some tumours regress spontaneously. Urinary screening programmes or clinical examination may detect the disease before symptoms appear, but the benefit of early diagnosis is uncertain. We examined the incidence, pattern, and presentation of neuroblastoma in four European countries.

METHOD

Population-based incidence rates were derived for France, Austria, Germany, and the UK. Age, sex, and stage distribution were analysed by Mantel-Haenszel techniques and Poisson regression. The proportion of incidental diagnoses (cases without symptoms found at routine health checks or during investigation of other disorders) and mortality rates were also compared.

FINDINGS

Between 1987 and 1991, 1672 cases of neuroblastoma were diagnosed in children under 15 years old (France, 624; Austria, 69; Germany, 493; UK, 486). Age-standardised annual incidence was significantly lower in the UK (10.1/million) than in France (12.5) and Germany (11.4). In the UK a deficit of low-stage disease in infants was accompanied by an excess of stage IV in older children. The UK had significantly fewer incidental diagnoses (8%) than Austria (27%) and Germany (34%). UK mortality rates were significantly higher than German or French rates.

INTERPRETATION

In the UK, neuroblastoma diagnosis is delayed, possibly because of a less rigorous system of health checks for children. Although some overdiagnosis occurs in mainland Europe, our data suggest that in the UK some low-stage cases, undetected in infancy, may later present as advanced disease. This finding has implications for screening programmes and organisation of routine surveillance of infant health in the UK.

10 years' neuroblastoma screening in Europe: preliminary results of a clinical and biological review from the Study Group for Evaluation of Neuroblastoma Screening in Europe (SENSE)

Between January 1986 and May 1996, 870,313 children were tested in European neuroblastoma (NB) screening programmes. Among these children, 82 cases of NB (age range 4-24 months, median 11 months) were detected by screening. 83% of the patients had localised NB and 17% were diagnosed with generalised NB (stage 4, 10%; stage 4s, 7%). Unfavourable biological markers (MYCN amplification, loss of heterozygosity (LOH) 1p36, DNA di/tetraploidy) were observed in 14% of 76 biologically examined cases. The median follow-up time of all the patients was 21.5 months (range 1-101 months). To date, 69 patients are in complete remission (CR) and 2 patients have died due to therapy (stage 4, 1 patient; stage 3, 1 patient with unfavourable markers). Apart from screened patients, 16 other patients with NB were found who had previously had a normal screening test, i.e. 'false negative' patients (age range 10-41 months, median 31.5 months). The median interval between screening and diagnosis was 24.5 months (range 6-35 months). 11 of the 'false negative' patients suffered from generalised NB (stage 4) and 5 had localised NB at diagnosis. Unfavourable biological markers were observed in 7/12 patients. 5 patients have died, 2 achieved partial remission and 9 CR. 9 of the 11 patients with unfavourable biological markers diagnosed due to NB screening are currently in CR. It is very likely that, among the patients without unfavourable biological markers, we detected tumours which may have regressed spontaneously. These children may have undergone 'unnecessary,' but unavoidable, diagnostic procedures and therapy. To reduce the number of 'false negative' patients, a later screening could be helpful and should be evaluated.

Type of health care coverage and the likelihood of being screened for cancer

OBJECTIVES

This study explored whether type of outpatient health coverage affected the likelihood of men and women aged 20 to 64 years receiving recommended cancer screening procedures.

METHODS

Data from the 1989 and 1990 California Behavioral Risk Factor Surveillance Surveys were used to compare Pap smear, mammogram, fecal occult blood test, and proctoscopic examination rates for adults with three different types of private health care coverage (Group/staff model health maintenance organization, Independent Practice Association Model health maintenance organization, indemnity plan) and no outpatient health insurance. Logistic regression models were used to control for sociodemographic and health characteristics and whether individuals had a usual health care provider.

RESULTS

Individuals with Group Model health maintenance organization coverage were significantly more likely than those with indemnity plans to have had recent cervical, breast, and colorectal cancer screening, whereas screening likelihood for those with Independent Practice Association model health maintenance organization coverage did not differ substantially from those with indemnity plans. Individuals with no outpatient coverage were less likely to be screened than those with outpatient coverage. The most consistently significant predictor across cancer screening procedures for both men and women was having a usual doctor who knew their medical history.

CONCLUSIONS

Adults who had private outpatient insurance were more likely to undergo recommended cancer detection procedures than those who did not. Adults who belonged to a health maintenance organization, which emphasizes and pays for a broader spectrum preventive care, were more likely to receive Pap smears, mammograms, and fecal occult blood tests than those covered by indemnity plans. Receiving care primarily from one doctor significantly increased the likelihood of having screening procedures, irrespective of type of health plan.

The North Cumbria Community Genetics Project

The aim of the North Cumbria Community Genetics Project is to establish a store of DNA, plasma, and viable cells from a cohort of around 8000 Cumbrian infants. To meet this objective, specimens of umbilical cord blood and tissue will be collected with maternal consent from babies born at the West Cumberland Hospital, Whitehaven over a five year period from January 1996. These samples will be used in a series of genetic and epidemiological studies investigating the interaction between genes, the environment, and health. There is little population movement in West Cumbria and so it will be possible to follow many of the babies throughout their childhood and to investigate the relationship between their genetic constitution and health outcome.