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STUDY OBJECTIVE: To create new versions of the written, multiple-choice examination used in the American Heart Association (AHA) Advanced Cardiac Life Support course, evaluate their reliability and difficulty, and then design revised versions with improved reliability and of standardized difficulty. DESIGN: Psychometric evaluation of new versions of the AHA Advanced Cardiac Life Support test and revisions. SETTING: AHA Advanced Cardiac Life Support courses. PARTICIPANTS: Candidates for completion of AHA Advanced Cardiac Life Support provider courses in five states. INTERVENTION: The course content was divided into 11 content areas that were weighted for importance and appropriateness for testing in a multiple-choice format. The weights were used to construct a blueprint for a 50-question, multiple-choice examination. Five versions of the examination were then constructed based on the content blueprint, drawing from new questions and expert revision of previously written questions. Reliability and difficulty were assessed using 915 administrations at five different sites nationwide. The initial test versions differed in their degree of difficulty, which was not explained by demographic factors. The results were used to revise three of the versions to improve reliability and equalize difficulty of the versions. MEASUREMENTS AND MAIN RESULTS: The final five versions have estimated reliability ranging from Cronbach's alpha of .62 to .86. Mean scores ranged from 87.4% to 89.1%. CONCLUSION: After field testing and revision, five examinations with acceptable reliability and roughly equal difficulty were constructed. The new examinations test the participants' knowledge of important aspects of resuscitation science and practice based on a blueprint of the course content.

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Medical education faces increasing criticism because of the perception that it is difficult to produce physicians who are both technically competent and compassionate. One approach to addressing this problem is to train physicians to address the emotional concerns that patients experience as a result of their medical problems. Results of the authors' randomized, controlled experiment in training medical students to respond to patients' emotional concerns provide evidence of the efficacy and feasibility of such training. Only students who received small-group instruction in addition to large-group lectures exhibited statistically significant (p less than .001) improvement in their ability to respond to the emotional concerns of patients in hypothetical cases. The students who received only the lectures exhibited significant improvement (p less than .001) in their preference for responses that addressed patients' emotional concerns but not in their responses to written, hypothetical patient cases. Even though these students' preferences for responses to emotional concerns on the average did increase significantly, the preferences were significantly (p less than .001) less favorable than the preferences of the students who received small-group instruction. The small group instruction consisted of both interviews with elderly nursing home residents, who served as simulated patients, and structured practice and review sessions.

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During the aerobic conversion of xanthine to uric acid by xanthine oxidase, superoxide anion and hydrogen peroxide are produced along with the hydroxyl radical. Our studies demonstrate that washed human platelets incubated with xanthine and xanthine oxidase aggregated and released [14C]serotonin. Aggregation and release were dependent on the duration of exposure to xanthine oxidase as well as the concentration of enzyme. Both reactions were inhibited by the superoxide scavenger enzyme superoxide dismutase but not by catalase, or the free radical scavenger mannitol, suggesting that they were induced by superoxide anion. Superoxide-dependent release was inhibited by prior incubation of platelets with 1 mM EDTA, 1 micronM prostaglandin E1, or 1 mM dibutyryl cyclic AMP, but was unaffected by 1 mM acetylsalicylic acid or 1 micronM indomethacin. After prolonged incubation with xanthine and xanthine oxidase there was also efflux of up to 15% of intraplatelet 51Cr, a cytosol marker. This leakage was prevented by the addition of catalase to the media but not by superoxide dismutase. Incubation with xanthine and xanthine oxidase did not produce malonyldialdehyde, the three-carbon fatty acid fragment produced during prostaglandin endoperoxide synthesis and lipid peroxidation. Prior exposure of platelets to low fluxes of superoxide anion lowered the threshold for release by subsequent addition of thrombin, suggesting a synergistic effect. We conclude that superoxide-dependent aggregation and release may be a physiologically important method to modulate hemostatic reactions particularly in areas of inflammation or vessel injury which could have high local concentrations of superoxide anion.

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Platelets in an infant with Chediak-Higashi (C-H) syndrome without bleeding manifestations and not in the accelerated phase showed abnormal function consistent with storage pool disorder as shown by abnormal aggregation, decreased storage capacity and release of [14C]5-HT, low endogenous 5-HT, reduced ATP and ADP with an increased ATP/ADP ratio, increased specific radioactivity of ADP after [14C]adenine labelling, decreased release of adenine nucleotides after stimulation, impaired secretion of acid hydrolases despite normal stores, and decreased calcium content. Incorporation of [14C]adenine into metabolic pool adenine nucleotides was normal. Nucleotide conversion to hypoxanthine in stimulated platelets was mildly impaired. Platelet cyclic-AMP (c-AMP) was initially elevated, but even when c-AMP returned to normal levels after ascorbate treatment, platelet function was not improved. Elevated intracellular c-AMP was not solely responsible for the abnormal platelet function.

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Serologic tests for antineutrophil antibodies were used to determine if autoantibodies cause neutropenia. The serums of five patients with idiopathic neutropeniaopsonized normal neutrophils, causing them to be ingested by rabbit macrophages or else to activate glucose oxidation rates of other normal neutrophils by at least twice the rate of controls. Some of the serums inhibited the ability of normal neutrophils to ingest by 62 to 56 per cent. At splenectomy in two of the patients splenic macrophages contained ingested neutrophils, suggesting that the opsonic activity of the serum demonstrated in vitro had pathogenetic importance. In two adults, and possibly in an infant, corticosteroids raised the neutrophil count, although antibody activity remained in the serum of the adults. The findings indicate that autoantibodies are the basis of some cases of idiopathic neutropenia, and that they act by promoting the clearance of neutrophils by mononuclear phagocytes.

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