Minimum Number Of Cases Research Articles

Training and the European Working Time Directive: a 7 year review of paediatric anaesthetic trainee caseload data

The implementation of the European Working Time Directive (WTD) has reduced the hours worked by trainees in the UK to a maximum of 56 h per week. With a further and final reduction to 48 h per week scheduled for August 2009, there is concern amongst doctors about the impact on training and on patient care. Paediatric anaesthesia is one of the specialist areas of anaesthesia for which the Royal College of Anaesthetists (RCoA) recommends a minimum caseload during the period of advanced training. We conducted a retrospective analysis of theatre logbook data from 62 Specialist Registrars (SpRs) who had completed a 12 month period of advanced training in paediatric anaesthesia in our institution between 2000 and 2007. After the implementation of the WTD 56 h week in 2004, the mean total number of cases performed by SpRs per year decreased from 441 to 336, a 24% reduction. We found a statistically significant reduction across all age groups with the largest reduction in the under 1 month of age group. The post-WTD group did not meet the RCoA recommended total minimum caseload or the minimum number of cases of <1 yr of age. Since the implementation of the WTD, there has been a significant reduction in the number of cases performed by SpRs in paediatric anaesthesia and they are no longer achieving the RCoA recommended minimum numbers for advanced training.

Lymphatic mapping and sentinel lymph node detection in women with cervical cancer

Lymphatic mapping and sentinel node detection have been applied to almost every solid tumor and sentinel node status have become part of the American Joint Commission on Cancer (AJCC) staging criteria in both breast cancer and malignant melanoma. As the presence of metastatic disease in lymph nodes is the most important prognostic factor on survival in women with cervical cancer, the ability to reliably detect sentinel nodes might triage women to adjuvant radiotherapy without the need for full lymphadenectomies and their associated morbidity. To date, multiple international investigators have performed single institution investigations with promising results. Overall, 831 women have been undergoing lymphatic mapping and sentinel node detection as part of their cervical cancer therapy as reported in the literature. Combining results from all these studies, a sentinel node was identified in 90% of cases with an overall sensitivity of detecting metastatic disease of 92% with an 8% false negative rate. The overall negative predictive value was over 97%. There remain controversies in moving forward with accepting sentinel node biopsy as the standard in treating women cervical cancer including 1) determining an acceptable false-negative rate, 2) establishing the importance of micrometastatic disease or isolated tumor cells in sentinel nodes, and 3) discovering the minimum number of cases a surgeon needs to become proficient in mapping techniques. Large, multi-institutional studies in both Europe and the United States are nearing completion and their results should help guide the future direction for sentinel node technologies in the treatment of cervical cancer.

Transplants in Foreign Countries Among Patients Removed from the US Transplant Waiting List

Transplant tourism, where patients travel to foreign countries specifically to receive a transplant, is poorly characterized. This study examined national data to determine the minimum scope of this practice. US national waiting list removal data were analyzed. Waiting list removals for transplant without a corresponding US transplant in the database were reviewed via a data validation query to transplant centers to identify foreign transplants. Additionally, waiting list removal records with text field entries indicating a transplant abroad were identified. We identified 373 foreign transplants (173 directly noted; 200 from data validation); most (89.3%) were kidney transplants. Between 2001 and 2006, the annual number of waiting list removals for transplant abroad increased. Male sex, Asian race, resident and nonresident alien status and college education were significantly and independently associated with foreign transplant. Recipients from 34 states, plus the District of Columbia, received foreign transplants in 35 countries, led by China, the Philippines and India. Transplants in foreign countries among waitlisted candidates in the US are increasingly performed. The data reported here represent the minimum number of cases and the full extent of this practice cannot be determined using existing data. Additional reporting requirements are needed.

Proficiency of GI Trainees in Achieving Quality Benchmarks in the Performance of Colonoscopy

Background: The American Society for Gastrointestinal Endoscopy (ASGE) quality indicators for colonoscopy include: 1) Adenoma detection rate (ADR) ≥25% among men over the age of 50, and 2) Cecal intubation rate (CIR) ≥95%. Aims: 1) Determine if graduating GI fellows meet ASGE goals for ADR and CIR. 2) Compare graduating trainees and attendings for ADR and CIR 3) Determine the point in training at which goals for ADR and CIR are achieved. Methods: This study analyzed colonoscopies performed at the San Diego VA for colorectal cancer screening or polyp surveillance. A total of 2573 trainee colonoscopies conducted with minimal attending supervision and 758 colonoscopies performed by attendings alone were included. Cecal intubation was determined by photo-documentation of anatomic landmarks. Pathology was accessed to assess for adenomas and mean ADR and CIR for trainees and attendings were calculated. Because 96% of VA patients were male, only ADR for men ≥age of 50 was used. Fellows' ADR and CIR were compared to ASGE benchmarks and to attendings' ADR and CIR. Results: Trainee ADR was 44% (95% CI: 41-47%) and CIR was 95% (95% CI: 93-96%). Fellows met both benchmarks by the end of the first year (Figure 1) with an average of 149 cases completed. ADR and CIR were 44% and 95% throughout all levels of training. Performance measures among trainees and attendings were not statistically different. Conclusions: Trainees achieved ASGE benchmarks in the performance of colonoscopy by the end of the first year when 149 cases were completed. This validates the minimum number of cases (140) established by the ASGE for competency assessment. Further studies will need to assess other measures that should be incorporated in teaching trainees the performance of quality colonoscopy.

Standards for Gastroenterologists for Performing and Interpreting Diagnostic Computed Tomographic Colonography

Standards for Gastroenterologists for Performing and Interpreting Diagnostic Computed Tomographic Colonography

Evolving Practice Patterns in Colon and Rectal Surgery

Minimum numbers of cases required for certification by the American Board of Colon and Rectal Surgery (ABCRS) have been determined from a prospective database of all applicants applying for examination since 1989. These data represent the longitudinal evolution of practice patterns in tertiary colorectal training programs. After obtaining permission from the ABCRS, access to the database was obtained and data from the 12-year period 1994 to 2005 were analyzed. The database contains the operative and endoscopic case numbers of 673 residents. The number of training programs increased from 28 to 39 (28%) and the number of residency positions from 50 to 66 (24%). Median numbers of anorectal patients per resident remained remarkably constant over the period of study. Both rigid sigmoidoscopy (67 to 44 per resident) and flexible sigmoidoscopy (135.5 to 39 per resident) decreased substantially; colonoscopy volume increased (209 to 264 per resident). Perineal procedures for rectal prolapse consistently comprise 50% to 60% of the total procedures for prolapse. Low anterior resection for rectal cancer outnumber abdominoperineal resections by a 3/1 ratio. Coloanal anastomoses have steadily increased. Laparoscopic approaches for all abdominal operations have increased substantially, with the greatest increase being in diverticular resections (6.5% to 44.7%). Prospective data collection by ABCRS has permitted calculation of minimum numbers of operative cases for training colorectal surgeons, with the advantage of a rolling average that reflects evolving practice patterns in teaching programs. Analysis of these data allows planning of needs-based educational programs and may ultimately be involved in designing the maintenance of certification process.

Geographic Pathology of Helicobacter pylori Gastritis

Helicobacter pylori is etiologically associated with gastritis and gastric cancer. There are significant geographical differences between the clinical manifestation of H. pylori infections. The aim of this study was to compare gastric mucosal histology in relation to age among H. pylori-infected patients from different geographical areas using the same grading system. The prevalence of atrophy and intestinal metaplasia were also compared with the respective gastric cancer incidence in the different countries. A total of 1906 patients infected with H. pylori from seven countries were evaluated. Entry criteria included H. pylori positive cases with antral and corpus biopsies between the ages of 18 and 75 years. The minimum number of cases required from a country was 100. Hematoxylin-eosin stained biopsies from antrum and corpus were scored semiquantitatively using the parameters suggested by the Sydney Classification System. Statistical evaluation was performed using Kruskal-Wallis test and Spearman's rank correlation test. The severity of gastric atrophy varied among the different groups with the highest scores being present in Japan. The lowest scores were found in four European countries and in Thailand. The scores for intestinal metaplasia were low in general except for Xi-an, Japan, and Shanghai. For all the countries, the presence of atrophy in the antrum correlated well (r = 0.891) with the incidence of gastric cancer. Using a standardized grading system in a large study of H. pylori-related geographic pathology, we found major differences in the overall prevalence and severity of H. pylori gastritis in relation to age. These differences mirrored the respective incidences of gastric cancer in those geographical areas.

From the many to the few: changes in urological cancer surgery provision

From the many to the few: changes in urological cancer surgery provision

Surgical death rates are not a reliable measure of hospital quality

Question Are enough surgical procedures performed to use surgical mortality rates as a reliable measure of hospital quality? Study design Cohort study Main results In a 3-year observation period, 90% of hospitals performing coronary artery bypass graft (CABG) surgery exceeded the minimum number of cases needed to reliably detect poor performance (see Results table). However, only a small proportion of hospitals exceeded the minimum number of cases for craniotomy, paediatric heart surgery, repair of abdominal anuerysum, pancreatic resection, oesophageal resection and hip replacement. Altering the definition of poor performance from twice to 1.5 times the national average death rate for each procedure significantly reduced the number of hospitals that exceeded the minimum number of cases (data not shown). When the observation period was increased to 5 years, CABG surgery was still the only procedure that exceeded the minimum number of cases (data not shown). Authors’ conclusions Mortality from CABG surgery may be a useful measure of hospital quality. Craniotomy, paediatric heart surgery, repair of abdominal aneurysm, pancreatic resection, oesophageal resection or hip replacement are not performed frequently enough and an alternative quality indicator for these procedures should be found.

Use of tissue microarray for interlaboratory validation of HER2 immunocytochemical and FISH testing

Aims: To evaluate the use of tissue microarray (TMA) technology as a validation tool for HER2 testing by both immunocytochemistry (ICC) and fluorescence in situ hybridisation (FISH) in the diagnostic...

The problems of sclerosing encapsulating peritonitis on long-term CAPD

Consideration of psychiatric and psychosocial factors is important for the management and prevention of dermatologic disorders. Dermatology patients suffer commonly from psychiatric comorbidity.To study pattern and prevalence of psychiatric disorders among patient attending dermatology OPD.The study was carried out in Psychiatry department of NIMS Medical College, Jaipur, Rajasthan, a north State of India. The sample was taken from Dermatology department of Medical College. All the participants were diagnosed/confirmed cases of skin diseases. Socio-demographic data was collected. Patients scoring more than 12 on GHQ were examined for presence of psychiatric illness. Clinical interview & Mental Status Examination (MSE) of these patients was carried out to ascertain diagnosis according to ICD-10.As per ICD-10 diagnosis 34.2% of total sample were diagnosed with definite Psychiatric comorbidity. Maximum number of cases were of Depression 36.32% (N = 146) followed by Anxiety disorder 18.41% (74) and 7.96% (N = 32) with Somatoform disorder. Obsessive compulsive disorder was diagnosed in 6.47% (N = 26) followed by Adjustment disorder 4.98% (N = 20) and Alcohol dependence syndrome 4.98% (N = 20). Minimum number of cases belonged to Schizophrenia 2.99% (N = 12) and Bipolar Affective Disorder 2.99% (N = 12). No diagnosis was found in 14.93% (N = 60).Significant psychiatric comorbidity exists in patients of dermatology. Biopsychosocial approach to patients with skin disease should be sought by liaison between psychiatrist and dermatologist.

Is the incidence of fetal-to-maternal hemorrhage increased in patients with third-trimester bleeding?

Objective: If a pregnancy is complicated by third-trimester bleeding, is there a higher risk of fetal-to-maternal hemorrhage that might necessitate the administration of additional anti-D immune globulin to prevent alloimmunization in the patient who is Rh D-negative? The study objective was to analyze prospectively the incidence of fetal-to-maternal hemorrhage in pregnancies that were complicated by third trimester bleeding compared with three control groups. Study Design: Pregnancies that were complicated by third-trimester bleeding, preterm premature rupture of the membranes, and preterm labor were identified prospectively on admission. A group of preterm patients with no complications was also collected prospectively. Patients with any history and/or clinical evidence of trauma were excluded. Kleihauer-Betke tests were performed with all patients, and the results were blinded until study completion. Sample size calculations were performed to determine the minimum number of cases needed in each group. Results: A total of 403 patients were collected during the study period: 91 patients had third-trimester bleeding, 101 patients had preterm premature rupture of the membranes, 116 patients had preterm labor, and 95 patients were in the no complication group. There was no statistical difference identified in the Kleihauer-Betke test results between any of the study groups. Conclusion: The incidence of fetal-to-maternal hemorrhage does not appear to be increased in pregnancies that are complicated by third-trimester bleeding when compared to noncomplicated control subjects or to other obstetrically complicated pregnancies. This information would suggest that the routine administration of additional anti-D immune globulin (beyond the current recommended protocol) to women who are Rh D-negative whose pregnancies are complicated by third-trimester bleeding is not indicated. (Am J Obstet Gynecol 2003;188:1615-21.)

Congenital heart disease outcome analysis: Methodology and rationale

Congenital heart disease outcome analysis: Methodology and rationale

The learning curve and sentinel node biopsy

Background: The ability of sentinel node biopsy (SNB) to replace axillary node dissection for accurate breast cancer staging is absolutely dependent on the consistent and accurate determination and removal of the “true” sentinel node. There are a wide variety of variables that affect the ability of the physician to achieve this goal. One important and potentially controllable variable is physician training and competence to employ the available techniques successfully. There is a large diversity of opinion regarding the minimum number of cases required under supervision prior to independent utilization of the technique but there are data to support at least 20 cases done in conjunction with axillary dissection or under direct supervision. Methods: Data from single institution and multicenter trials are reviewed and the learning curves are described. An overview of surgical education methods, testing, and credentialing is also addressed. Results: A review of single institution series show that the false negative rate and identification rates vary considerably. In all cases where authors published a second series success rate improved compared with their initial series. Of the four multicenter trials only two can provide reliable learning curves and these have shown a decrease in the false negative rate to ≤5% after 20 to 30 procedures are performed. Conclusions: There are data to show that there is a definite learning curve for SNB that cannot be ignored. It is possible that other factors, (ie, a skin injection with technetium-99, Sappeys plexus injection, and mentoring) could decrease this learning curve but until compelling evidence to suggest otherwise is available, surgeons should obtain a minimum experience of 20 cases.

A prospective analysis of 13,580 colonoscopies. Reevaluation of credentialing guidelines.

The aims of this study were to assess the safety and efficacy of surgeons performing colonoscopy, and to use the results to reevaluate currently available credentialing guidelines. A prospective outcomes study was designed to include all members of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES). End points were related to the efficacy and safety of colonoscopy. Credentialing guidelines were reviewed. Between April 1998 and September 1999 13,580 colonoscopies were prospectively entered into a database. The most common indications were rectal bleeding, colonic polyps, and change in bowel habits. The colonoscopy was normal or revealed only diverticulosis or nonspecific inflammation in 8,473 (62.4%), lower gastrointestinal bleeding in 4 (0.03%), polyps in 4,645 (34.2%), and tumors in 458 (3.4%) patients. The most common biopsy methods for polyps or tumors were the snare (n = 1,728; 34%), the hot (n = 1,600; 31%), and the cold (n = 1,340; 22%) procedures. The colonoscopy was complete in 12,495 cases (92%), requiring a mean procedure time of 22.7 min (range, 1-170 min). Intraprocedural complications included arrhythmia (n = 14; 0.1%), bradycardia (n = 115; 0.8%), hypotension (n = 171; 1.2%), and hypoxia (n = 806; 5.6%). Postprocedural complications were seen in 27 patients (0.2%). Bleeding (n = 10; 0.07%) was managed by observation alone (n = 9; 0.06%) and repeat colonoscopy with transfusion (n = 1; 0.01%). Perforation (n = 10; 0.07%) was treated successfully by observation with conservative management (n = 5; 0.05%) and surgery (n = 5; 0.05%); severe abdominal pain (n = 4; 0.03%) was managed by observation and conservative therapy; and bronchospasm (n = 2; 0.015%) was managed by observation and supportive care. One single mortality (0.007%) was that of a 70-year-old man with a massive lower gastrointestinal hemorrhage who had a cardiac arrest in the recovery room following colonoscopy. The complication rate was not significantly associated statistically with either the level of experience or the number of prior or annual colonoscopies. However, prior colonoscopic experience did have an impact on the completion rate (p < 0.001) and was inversely proportional to the time to completion (p < 0.001). Similarly, the number of annual colonoscopies affected the completion rate and was inversely correlated with the time to completion (p < 0.001). This large prospective outcomes study showed that colonoscopy performed by surgeons can be rapidly and successfully done with acceptably low morbidity and mortality. There was no association between experience and complications. However, a minimum of 50 prior colonoscopies and 100 annual colonoscopies were associated with a significant improvement in the rate of completion. There was also a significant correlation between both prior and ongoing annual experience and the time required for the examination. No minimum number of cases can be mandated for credentialing to perform "safe" colonoscopies.

Proficiency in neurosurgery.

This evaluation of proficiency is a comparison of other high performance occupations with neurosurgeons, an attempt to understand the minimal number of cases required for proficiency during both residency training and after, and the effect of human factors.

Dispelling the myths and misconceptions about transumbilical breast augmentation.

Since its invention in 1991, the transumbilical breast augmentation (TUBA) technique has gained popularity, and it has been proven safe and effective. In addition, the technique has several advantages over other methods of breast augmentation. Nevertheless, the method has often been the subject of a great variety of criticisms. Careful examination of those criticisms reveals that most are, in fact, untrue; they are misconceptions at best and falsehoods at worst. In this article, the author examines the 20 most common misconceptions about this procedure, clarifies or corrects them as appropriate, and suggests possible reasons for their having arisen in the first place. In addition, the actual drawbacks of the technique are reviewed. The author also outlines what he considers to be the criteria necessary for a surgeon to criticize any technique being used successfully by others: the surgeon must have proper plastic surgical training and certification, have completed training in the specific technique, and have a personal experience with performing a minimum number of cases.

Elemental Subsets: The Building Blocks of Regression

In a regression dataset an elemental subset consists of the minimum number of cases required to estimate the unknown parameters of a regression model. The resulting elemental regression provides an exact fit to the cases in the elemental subset. Early methods of regression estimation were based on combining the results of elemental regressions. This approach was abandoned because of its computational infeasibility in all but the smallest datasets and because of the arrival of the least squares method. With the computing power available today, there has been renewed interest in making use of the elemental regressions for model fitting and diagnostic purposes. In this paper we consider the elemental subsets and their associated elemental regressions as useful “building blocks” for the estimation of regression models. Many existing estimators can be expressed in terms of the elemental regressions. We introduce a new classification of regression estimators that generalizes a characterization of ordinary least squares (OLS) based on elemental regressions. Estimators in this class are weighted averages of the elemental regressions, where the weights are determined by leverage and residual information associated with the elemental subsets. The new classification incorporates many existing estimators and provides a framework for developing new alternatives to least squares regression, including the trimmed elemental estimators (TEE) proposed in this paper.

Volume requirements for cardiac surgery credentialing: A critical examination

New volume requirements for coronary artery bypass grafting are being imposed on cardiac surgeons by hospitals, managed care groups, and others. The rationale for this is unclear. The available literature as well as additional sources relating volume and outcomes in cardiac surgery were extensively reviewed and reexamined. There are no data to conclusively indicate that outcomes of cardiac operations are related to a specific minimum number of cases performed annually by a cardiac surgeon. Each cardiothoracic surgeon should participate in a national database that permits comparison of his or her outcomes on a risk-adjusted basis with other surgeons. Until conclusive data become available that link volume to outcome, volume should not be used as a criterion for credentialing of cardiac surgeons by hospitals, managed care groups, or others. Instead, each surgeon should be evaluated on his or her individual results.

Future etiologic research in occupational cancer.

Research focused on occupational exposure has been one of the cornerstones of epidemiological research into the etiology of cancer. It is appropriate to critically assess the contribution of this research effort and to assess the potential for making significant progress in the future in unraveling the etiology of cancer by studying the occupational environment. The study of the occupational environment has indeed been very fruitful. It is likely that there remain many more carcinogens to be discovered, but we have not deployed adequately sensitive study methods. The two major obstacles to quality research have been inadequate exposure assessment and insufficient sample sizes. Quality exposure assessment requires the participation of trained experts (industrial hygienists, chemists, etc.); it also requires an adequate information base on the exposures that occur in different workplaces. We need structures and career paths that facilitate the participation of exposure experts in epidemiological research. We need active large-scale industrial hygiene surveys to better characterize the U.S. workplace. This will be useful for epidemiological studies and for public health purposes. Community-based case-control studies will need to be much larger than they have been traditionally, with 1000 as a minimum number of cases and controls.