Objective assessment of learning curves for the Voxel-Man TempoSurg temporal bone surgery computer simulator.

INTRODUCTION: Simulators are becoming an increasingly important part of surgical training. Temporal bone surgery is one area in which simulators, such as the Voxel-Man TempoSurg simulator, are likely to play a significant role in training. We present learning curve data from novice trainees using this simulator to learn cortical mastoidectomy, exposure of the sigmoid sinus, and exposure of the short process of the incus. METHODS: We measured the time taken to perform the procedures, the volume of reference bone removed, and the structures damaged during dissection. RESULTS: We found improvement in a number of parameters over the course of the study. The overall scores, structural damage scores and time taken improved, to differing degrees, for each task. The volume of reference bone removed remained constant. CONCLUSION: These results indicate that the trainees' efficiency improved as they became more proficient at removing a given volume of reference bone.

Impact of a national external quality assessment scheme for breast pathology in the UK.

BACKGROUND: This article presents the results and observed effects of the UK National Health Service Breast Screening Programme (NHSBSP) external quality assurance scheme in breast histopathology. AIMS/METHODS: The major objectives were to monitor and improve the consistency of diagnoses made by pathologists and the quality of prognostic information in pathology reports. The scheme is based on a twice yearly circulation of 12 cases to over 600 registered participants. The level of agreement was generally measured using kappa statistics. RESULTS: Four main situations were encountered with respect to diagnostic consistency, namely: (1) where consistency is naturally very high-this included diagnosing in situ and invasive carcinomas (and certain distinctive subtypes) and uncomplicated benign lesions; (2) where the level of consistency was low but could be improved by making guidelines more detailed and explicit-this included histological grading; (3) where consistency could be improved but only by changing the system of classification-this included classification of ductal carcinoma in situ; and (4) where no improvement in consistency could be achieved-this included diagnosing atypical hyperplasia and reporting vascular invasion. Size measurements were more consistent for invasive than in situ carcinomas. Even in cases where there is a high level of agreement on tumour size, a few widely outlying measurements were encountered, for which no explanation is readily forthcoming. CONCLUSIONS: These results broadly confirm the robustness of the systems of breast disease diagnosis and classification adopted by the NHSBSP, and also identify areas where improvement or new approaches are required.

A structured assessment of newly qualified medical graduates.

INTRODUCTION: While there is extensive published experience with the assessment of procedural skills in undergraduate students, this is limited in newly qualified medical graduates at the time of entry to the pre-registration (internship) year. The few studies that have been published suggest that these skills are frequently deficient when objectively tested. We therefore chose to assess the competence of a group of South African medical graduates on entry to their pre-registration year. METHODS: A total of 58 graduates of South African medical schools were assessed. Each subject participated in a 7-station objective structured clinical examination (OSCE); 6 of these assessed individual competence in phlebotomy, intramuscular injection, female pelvic examination, bladder catheterisation, tracheal intubation and prescription writing, while competence in cardiopulmonary resuscitation was assessed in a seventh station in randomly allocated teams of 3 candidates. Candidates' opinions of their own competence was sought by questionnaire. RESULTS: There was a wide variation in competence between subjects and across the range of tasks studied. Mean scores ranged from 85.4% for phlebotomy to 55.3% for prescription writing. The average score across all stations was 67.5%, and no student obtained an overall cut-off score of 85% or more, which was established using a modified Angoff method. Subjects' assessment of their own performance was unduly optimistic; most believed that they had demonstrated competence despite clear shortcomings in technique. Objective scores for subjects who had been exposed to a structured skills laboratory programme were not significantly higher than for those who had not, although their self-assessed performance was indeed higher. DISCUSSION: Most of the South African medical graduates who participated in this study were unable to satisfactorily perform technical procedures appropriate to the house officer on entry to the pre-registration year. This is in line with the conclusions of the few studies published in other countries. We suggest that the learning outcomes of undergraduate medical programmes should include an explicit statement of the competencies required for practice in the pre-registration year, and that these should be adequately taught and rigorously assessed before graduation.

Assessment of myocardial hypertrophy by echocardiography in adult patients receiving tacrolimus or cyclosporine therapy for prevention of acute GVHD.

The incidence of myocardial hypertrophy was determined in a comparative study of tacrolimus-based immunosuppression with cyclosporine-based immunosuppression for prevention of acute graft-versus-host disease (GVHD) after unrelated donor bone marrow transplantation. Patients were evaluated for clinical and echocardiographic abnormalities at baseline (prior to pretreatment conditioning and the first dose of study drug) and at 5-8 weeks after transplant when stable levels of oral tacrolimus or cyclosporine had been achieved. Left ventricular geometry and performance were assessed by echocardiography which included 2-D measurements and one Doppler measurement. Derived echocardiographic measurements and left ventricular mass index (LVMI) were also determined. A cut-off of <111 g/m(2) was used for the upper limit of normal for LVMI. Forty-four patients were included in this study (21 tacrolimus and 23 cyclosporine), of which 31 were evaluable for a comparison with both baseline and post-transplant values. There was no significant difference in the changes from baseline for mean left ventricular mass (LVM) or LVM index (LVMI) between treatment groups. Also, within the tacrolimus group there were no significant changes for these variables from baseline to post-transplant evaluations. Within the cyclosporine group there were significant increases from baseline for mean LVM (P = 0.011) and LVMI (P = 0.007). The incidence of myocardial hypertrophy (change of LVMI from <111 g/m(2) baseline to >111 g/m(2) post transplant) was 20% in the tacrolimus group and 56% in the cyclosporine group (P = 0.109). Changes in the LVMI from baseline to post baseline were greater with cyclosporine than with tacrolimus therapy, and there was no evidence that tacrolimus causes myocardial hypertrophy or significant clinical changes in adult bone marrow transplant patients. The increase in LVMI after transplant in the cyclosporine group was greater than in the tacrolimus group but was not associated with any significant clinical events.

Reduced dose intravenous immunoglobulin does not decrease transplant-related complications in adults given related donor marrow allografts.

Graft-vs.-host disease (GVHD) and infection are major complications of allogeneic bone marrow transplantation. Intravenous immunoglobulin (IVIg) given at a dose of 500 mg/kg/wk has been shown to decrease the risk of acute GVHD, interstitial pneumonia, and infection in adults early after allogeneic transplantation. The current study is a controlled trial to determine whether a lower total dose of IVIg given with pretransplant loading reduces the incidence of transplant-related complications. In a randomized trial of 241 patients > or =20 years of age who were given related donor marrow allografts, 121 individuals receiving Ig prophylaxis (500 mg/kg/d loading from day -6 to -1 and then 100 mg/kg every 3 days from day 3 to 90) were compared with 120 control patients who did not receive IVIg. Randomization was stratified by human leucocyte antigen-matching, remission status of malignancy, GVHD prophylaxis, and cytomegalovirus (CMV) serology. The study was powered to detect a reduction in acute GVHD by 18% and a decrease in transplant-related mortality by 17%. Pretransplant IVIg loading and posttransplant maintenance achieved median serum IgG levels >1350 mg/dL, which were approximately twofold greater than the untreated controls (p<0.01). White blood cell and platelet recoveries were similar for the two groups, although control patients required fewer units of platelets per day (2.5 vs. 3.3, p = 0.008). No significant differences in the incidence of CMV infection, interstitial pneumonia, or bacteremia were observed. The incidence of acute GVHD did not differ between the two groups; however, acute GVHD was less frequent among IVIg recipients achieving maximum serum IgG levels >3000 mg/dL (60 vs. 79%). Neither transplant-related mortality nor disease-free survival was significantly altered by Ig prophylaxis. However, the cumulative incidence of relapse of malignancy was higher in IVIg recipients than in controls (31 vs. 18%, p = 0.03). Multivariable regression analysis demonstrated a 1.89 increased relative risk of relapse for individuals given IVIg (p = 0.021). We conclude that pretransplant loading and a shorter course and lower total dose of IVIg prophylaxis did not appear to decrease the risk of acute GVHD or mortality among adults receiving related donor marrow transplants. Note, IVIg administration may be associated with an increased risk of recurrent malignancy, a finding that warrants further investigation.

Stability of a perturbed Leslie model.

A small perturbation introduced in the stochastic Leslie model leads to a long-lived stable population in a region or parameter space where the stochastic model predicts the demise of the population. This somewhat surprising result is understood by considering a related model with a density-dependent sex ratio which exhibits similar features.

Core competencies create value.

In the past, healthcare providers have created value by delivering care on demand to their patients. In the future, however, providers will create value by mastering four core competencies: effective management of health and wellness, effective care delivery, effective population enrollment, and effective management of financial risk.