Reconsidering "good teaching" across the continuum of medical education.

There is no shortage of sustained inquiry into the nature and evaluation of teaching in medical education. For the most part, however, this growing and respectable body of inquiry has uncritically adopted a single model of effective teaching that is assumed to be appropriate across variations in context, learners, and teachers. This article presents five alternative views of "good teaching" and challenges the trend toward any single, dominant view of what constitutes good teaching. Based on 10 years of research, in five different countries, studying hundreds of educators in adult and higher education across a wide range of disciplines, contexts, and cultures, we have evidence of five different perspectives on good teaching: transmission, developmental, apprenticeship, nurturing, and social reform. Each perspective represents a philosophical orientation to knowledge, learning, and the role and responsibility of being an educator. A "snapshot" of each perspective is provided, including an example from continuing medical education (CME), a set of key beliefs, primary responsibilities, typical strategies, and common difficulties. Readers are encouraged to use the five perspectives as a means of identifying, articulating, and revisiting assumptions and beliefs they hold regarding their view of effective teaching. They are also encouraged to resist a "one-size-fits-all" approach to the investigation, improvement, or evaluation of teaching in CME.

Double-blind placebo-controlled pilot trial of acemannan in advanced human immunodeficiency virus disease.

SUMMARY: We assessed the safety and surrogate markers' effect of acemannan as an adjunctive to antiretroviral therapy among patients with advanced HIV disease receiving zidovudine (ZDV) or didanosine (ddI) in a randomized, double-blind, placebo-controlled trial of acemannan (400 mg orally four times daily). Eligible patients of either sex had CD4 counts of 50-300/microl twice within 1 month of study entry and had received 26 months of antiretroviral treatment (ZDV or ddI) at a stable dose for the month before entry. CD4 counts were made every 4 weeks for 48 weeks. P24 antigen was measured at entry and every 12 weeks thereafter. Sequential quantitative lymphocyte cultures for HIV and ZDV pharmacokinetics were performed in a subset of patients. Sixty-three patients were randomized. All were males (mean age 39 years). The mean baseline CD4 counts were 165 and 147/microl in the placebo and acemannan groups, respectively; 90 percent of the patients were receiving ZDV at entry. Six patients in the acemannan group and five in the placebo group developed AIDS-defining illnesses. There was no statistically significant difference between the groups at 48 weeks with regard to the absolute change or rate of decline at CD4 count. Among ZDV-treated patients, the median rates of CD4 change (ACD4) in the initial 16 weeks were - 121 and - 120 cells per year in the placebo and acemannan groups, respectively ( p = 0.45), ACD4 from week 16 to 48 was 0 and - 61 cells per year in the acemannan and placebo groups (p = .11), respectively. There was no statistical difference between groups with regard to adverse events, p24 antigen, quantitative virology, or pharmacokinetics. Twenty-four patients, 11 receiving placebo and 13 receiving acemannan, discontinued study therapy prematurely, none due to serious adverse reactions. Our results demonstrate that acemannan at an oral daily dose of 1600 mg does not prevent the decline in CD4 count characteristic of progressive HIV disease. Acemannan showed no significant effect on p24 antigen and quantitative virology. Acemannan was well tolerated and showed no significant pharmacokinetic interaction with ZDV.

Exit rounds: a reflection exercise.

This paper questions the long-held assumption that "experience is the best teacher". Reflection, it is argued, is the element that turns experience into learning. Unfortunately, reflection is the experiential learning skill in which student are most deficient. Further, clinical teachers may not appreciate the reciprocal and synergistic relationship of experience and reflection, and therefore they may not exploit its full potential. This paper argues for the formal and explicit use of reflection to clinical teaching. In addition to providing a theoretical rationale for the use of reflection is learning, one example of a reflection exercise--exit rounds--is described. Exit rounds focus on recently discharged patients and provide students with an opportunity to reflect on what they have learned from working with these patients. In addition to being a learning exercise, exit rounds provide attending physicians with an opportunity to address emotional issues, to evaluate students' learning and performances, to deal with "housekeeping" details, and to provide closure.

Clinical significance of scintillation camera electronics capable of high processing rates.

The use of larger scintillation detectors with high-efficiency converging collimators has greatly increased the photon input rate to the crystals of scintillation cameras in many clinical studies. To process these high-count-rate data accurately, modifications have been made by some manufacturers in the electronics of scintillation cameras. Cameras with new electronic design were compared with earlier models with respect to count rate processing capability and the effect of high input rate on spatial resolution, pulse-pair pileup, image size, and instability of the amplification of energy pulses. The improvements with the new electronic design result in shorter imaging times, better preservation of resolution, increased statistical reliability, and reduced distortion of dynamic tracer curves used for quantitative analysis.