Reliability and validity of an objective structured clinical examination for assessing the clinical performance of residents.

Clinical performance of residents should be assessed as reliably and validly as possible. This study investigated the reliability and validity of an objective structured clinical examination (OSCE) for assessing clinical performance of internal medicine residents. Residents were required to take a 17-patient OSCE in their first and second year. Reliability of the OSCE was 0.40. Validity studies indicated second-year students were significantly better than third-year students for five of six OSCE skill scores; first-year students were significantly better for three scores. Resident's scores for diagnosis, plan, and total significantly increased on their second OSCE. Generally faculty overall ratings of residents' clinical performance did not correlate with OSCE scores. American Board of Internal Medicine certifying examination scores were consistently positively correlated only with diagnosis. This 17-case OSCE is a feasible method for obtaining moderately reliable, valid data not available from other sources about the clinical performance of residents. More cases should be added to increase its reliability.

Review article: gastroduodenal bicarbonate secretion.

The gastroduodenal epithelium is covered by an adherent mucus layer into which bicarbonate is secreted by surface epithelial cells. This mucus-bicarbonate barrier is an important first line of defence against damage by gastric acid and pepsin, and has been demonstrated in all species including human. Similar to gastric acid secretion, regulation of gastric and duodenal bicarbonate secretion can be divided into three phases: cephalic, gastric and duodenal. In humans, sham-feeding increases bicarbonate secretion in both the stomach and duodenum which is mediated by cholinergic vagal fibres in the stomach, but seems to be noncholinergic in the duodenum. Gastric distention and luminal acidification increases gastric bicarbonate production. Whereas there are no data relating to the gastric phase of human duodenal bicarbonate secretion, in animals, food and acid in the stomach independently stimulate duodenal bicarbonate output. To date, the duodenal phase of human gastric bicarbonate secretion has not been studied, but data from animals reveal that duodenal acidification augments bicarbonate secretion in the stomach. In all species tested, direct acidification of the duodenum is a potent stimulant of local bicarbonate production. In humans, the pH threshold for bicarbonate secretion is pH 3.0. Mediation of gastroduodenal bicarbonate secretion is provided by a variety of agonists and antagonists, tested mainly in animals, but some have been evaluated in humans. Prostaglandins of the E class and VIP are major factors that control bicarbonate secretion. Bicarbonate secretion, and the mucus-bicarbonate layer in general, is adversely effected by ulcerogenic factors such as aspirin, NSAIDs, bile salts, and cigarette smoking. Furthermore, duodenal ulcer patients have an impairment in bicarbonate production within the duodenal bulb, at rest and in response to stimulation. These findings indicate that the mucus-bicarbonate barrier is an important first line of defence in the pathogenesis of peptic ulcer disease.

Setting standards and defining quality of performance in the validation of a standardized-patient examination format.

PURPOSE: To evaluate whether written standards increase the reproducibility of a physician-facilitated station in an objective structured clinical examination (OSCE) designed to assess history, physical-examination, and communication skills. METHOD: The OSCE examination at the University of Texas Medical Branch-Galveston consists of ten eight-minute stations. Six of these stations consist of three History, Physical-examination, Problem-solving, and Plan (HPPP) station pairs. Each existing clinical-problem HPPP station was given to two content experts to develop standards for faculty rating scales appropriate for the evaluation of third-year medical students. Three pairs of faculty members were used to determine interrater reliability by scoring videotapes of three HPPP stations' presentation and problem-solving components. Faculty pairs scored tapes of 15 students without using standards and tapes of 15 students using the standards developed. Differences between the reliabilities without and with the standards were tested for significance using Fisher's R to Z transformation. The reproducibility and standard error of measurement (SEM) were extrapolated for increasing amounts of testing time. The HPPP component scores were also correlated with the written examination scores and preceptors' ratings. Data were obtained from the three HPPP stations used in the 1995-96 internal medicine clerkship SP examination. RESULTS: In all, 196 students completed the OSCE examination. The standards developed improved interrater reliability and reached statistical significance (p < .01) for one HPPP station. Reproducibility for the presentation and problem-solving components of the HPPP stations were > .80 after five hours of testing. The problem-solving component correlated at .37 and .19 with written examinations and with ward grades, respectively. CONCLUSION: The data from this study suggest that standards increase the reproducibility of presentation and problem-solving components of an OSCE to a level as high as, or higher than, that associated with the history, physical-examination, and communication components of traditional standardized-patient examinations.

Creating and evaluating an independent ambulatory internal medicine clerkship.

Patient care is shifting from an inpatient setting to an ambulatory setting. Despite this shift, most internal medicine clerkships provide the majority of medical student training in inpatient settings or in university tertiary care clinics, which are not representative of patient care in a community setting. We created a separate ambulatory clerkship that used volunteer community faculty at local and distant sites. The steps involved are described here, including finding time within the clerkship, reaching consensus within the department, defining the curriculum, identifying sites, and developing preceptors. Various parameters were measured to ensure quality in educational design. Comparisons of the 1-year pilot program, the full implementation program, and the inpatient program revealed that use of community sites does not affect cognitive knowledge acquisition but does influence students' satisfaction level.

Dimensions of clinical competence as conceptualized by medical school faculty.

This study identified dimensions of clinical competence underlying faculty ratings of fourth-year student performance in a standardized patient examination and assessed the impact of these dimensions on faculty pass/fail decisions. Content review coupled with exploratory factor analysis was used to group 17 of 25 specific behavioral rating categories into four homogeneous clusters. Confirmatory factor analysis refined the clusters into four unidimensional scales that included 14 of the original ratings. The dimensions reflected relating to the patient, problem-solving skills, medical history skills, and physical examination skills. The factor structure was cross-validated in a separate data set. Logistic regression indicated problem solving was the only independent predictor of a student passing the exercise.

[Defence mechanisms of the gastroduodenal mucosa. The significance of epithelial and subepithelial factors for the development of acute and chronic ulceration]. / Gastroduodenalmukosaens forsvarsmekanismer. Betydningen af epiteliale og subepiteliale faktorer for udviklingen af akutte og kroniske ulcerationer.

Extra-epithelial, epithelial and sub-epithelial defence mechanisms protect the gastroduodenal mucosa against acid and pepsin. The epithelial mechanisms include epidermal growth factor, surface active phospholipids on the luminal membrane of the epithelial cells, sulfhydryl compounds and rapid epithelial restitution after damage. The sub-epithelial mechanisms include mucosal blood flow supplying the mucosa with bicarbonate needed for neutralization of the acid which penetrates the epithelium and the protective effect of the process of acid secretion. Prostaglandins, which partially protect the gastroduodenal mucosa against damaging agents, stimulate several of the abovementioned defensive factors but the precise mechanism of the action of prostaglandins is still unknown. The results of several experiments support the idea of the defensive factors being of importance in the development of acute and chronic gastroduodenal ulceration. At present, the therapeutic possibilities seem to be restricted and nothing indicates that stimulation of the defensive factors, only, is more effective in the treatment of peptic ulcer than inhibition of aggressive factors as acid and pepsin.

[Defense mechanisms of the gastroduodenal mucosa: the role of mucus and bicarbonate in the development of peptic ulcer]. / Gastroduodenalmucosa'ens forsvarsmekanismer: mucus' og bikarbonats betyndning for udviklingen af peptisk ulcus.

The existing knowledge of the mucus and bicarbonate production of the gastroduodenal mucosa is reviewed. Mucus and bicarbonate are produced in the surface epithelium of both duodenum and ventricle. The production is regulated by neural stimuli, gastrointestinal hormones and local synthesis of prostaglandins. Several of the factors suspected of being of importance to the development of peptic ulcers also have a negative influence on the production of mucus and bicarbonate. This indicates that mucus and bicarbonate are important in the pathogenesis of peptic ulcer. Two newly registered so-called mucosaprotective anti-ulcer drugs (De-Nol, Succralfat) both exert positive influences on the production of mucus and bicarbonate.

Genetic polymorphisms of tumour necrosis factor receptor superfamily 1b and fas ligand are associated with clinical efficacy and/or acute severe infusion reactions to infliximab in Crohn's disease.

BACKGROUND: Single nucleotide polymorphisms (SNPs) in TNF receptor superfamily (TNFRSF) 1A and 1B, and Fas ligand (FASLG) genes, have been associated with responsiveness to infliximab (IFX) in Crohn's disease. AIM: To investigate if SNPs in TNFRSF1A and 1B, and FAS (TNFRSF6) and FASLG (TNFSF6), associated with short- or long-term clinical and biological efficacy and with acute severe infusion reactions. METHODS: Observational, retrospective and explorative cohort study of IFX-treated Caucasian patients with Crohn's disease classified as primary nonresponders (n = 21), response failures on maintenance therapy (n = 37), maintained remission (n = 47) and occurrence of acute severe infusion reactions (n = 20). RESULTS: During IFX maintenance therapy, minor allele carriage of TNFRSF1B, rs976881 is associated with loss of response [OR 3.3 (1.2-9.1), P = 0.014]. Minor allele homozygosity increased the risk substantially (OR estimated 19, P = 0.006), and furthermore associated with a mean CRP increase of 17 mg/L as compared to a mean decrease of 17 mg/L in all others (P = 0.036). In contrast, minor allele carriage of TNFRSF1B, rs1061622 is associated with beneficial response to IFX induction [OR 4.2 (1.2-18.2), P = 0.014], and with persistence of remission during maintenance therapy [OR 5.5 (1.5-25.5), P = 0.007]. Carriage of the minor allele of FASLG, rs76110 increased risk of severe infusion reactions [OR 4.0 (1.1-22.4), P = 0.041]; minor allele carriage of TNFRSF1B, rs652625 decreased the risk (OR estimated 0.2, P = 0.043 ). CONCLUSIONS: The TNFRSF1B polymorphisms may contribute to predict efficacy of infliximab. Moreover, FASLG and TNFRSF1B polymorphisms may confer genetic susceptibility to severe infusion reactions. These findings could potentially aid clinical decisions if confirmed in larger studies.

Severe infusion reactions to infliximab: aetiology, immunogenicity and risk factors in patients with inflammatory bowel disease.

BACKGROUND: Infliximab (IFX) elicits acute severe infusion reactions in about 5% of patients with inflammatory bowel disease (IBD). AIM: To investigate the role of anti-IFX antibodies (Ab) and other risk factors. METHODS: The study included all IBD patients treated with IFX at a Danish university hospital until 2010 either continuously (IFX every 4-12 weeks) or episodically (reinitiation after >12 weeks). Anti-IFX Ab were measured using radioimmunoassay. RESULTS: Twenty-five (8%) of 315 patients experienced acute severe infusion reactions. Univariate analysis showed that patients who reacted were younger at the time of diagnosis (19 vs. 26 years, P=0.013) and at first IFX infusion (28 vs. 35 years, P=0.012). Furthermore, they more often received episodic therapy (72% vs. 31%, P<0.001) and logistic regression revealed this as the only significant predictor of reactions (OR 5 [2-13]; P<0.001). IFX reinitiation after 6 months intermission further increased the risk (OR 8 [3-20], P<0.001). Most reactions (n=14, 88%) occurred at 2nd infusion in the 2nd treatment series (P=0.006). Anti-IFX IgG Ab were highly positive in 19 of 20 patients (95%) shortly after the reactions (median 84 U/mL). Anti-IFX IgG Ab measured prior to the retreatment series were negative in 7 of 11 patients tested (64%). Anti-IFX IgE Ab were negative in all patients with reactions. CONCLUSIONS: Acute severe infusion reactions were strongly associated with development of anti-IFX IgG Ab, but not with anti-IFX IgE Ab. The risk was particularly high at the 2nd infusion in retreatment series. Negative anti-IFX Ab before reinitiation did not rule out reactions.