AMEE Guide No. 123 - How to read studies of educational costs.

Healthcare and health professions education share many of the same problems in decision making. In both cases, there is a finite amount of resources, and so choices need to be made between alternatives. To navigate the options available requires effective decision making. Choosing one option requires consideration of its opportunity cost - the benefit forgone of the other competing options. The purpose of this abridged AMEE guide is to introduce educational decision-makers to the economic concept of cost, and how to read studies about educational costs to inform effective cost-conscious decision-making. This guide leads with a brief review of study designs commonly utilized in this field of research, followed by an overview of how study findings are commonly presented. The tutorial will then offer a four-step model for appraising and considering the results of an economic evaluation. It asks the questions: (1) Can I trust the results? (2) What are the results telling me? (3) Could the results be transferred to my context? (4) Should I change my practice?

Antimicrobial Properties of α-Dicarbonyl and Related Compounds.

By surface plating on plate count agar, 0.005 M (430 ppm) of the α-dicarbonyl compound, diacetyl, inhibited 28 of 40 organisms with the medium at pH 6 but only 11 at pH 8. Diacetyl was more effective against gram-negative bacteria and yeasts than non-lactic gram-positive bacteria and least effective against lactic acid bacteria. Acetoin, butanedioldiacetate and five butanediol isomers were considerably less effective than diacetyl, although all were more effective at pH 6 than 8. Diacetylmonoxime and diacetyldioxime were more effective than the diols and were less affected by pH of medium than diacetyl. Phenylglyoxal (PG) and 1,2-cyclohexanedione (CHD) ranked closest to diacetyl but, unlike the latter, they were more effective against gram-positive bacteria and less so against fungi and gram-negative bacteria. All 12 compounds were more effective against selected organisms by pour plating and in broth culture than by surface plating. Like diacetyl, CHD and PG are α, α-dicarbonyls and are widely used as arginine reactive agents resulting in the blockage of enzyme-substrate reactions. Although their antimicrobial activity may be due to this property, they apparently affect different enzymes than diacetyl because their antimicrobial spectra were different. The possibility of a class of food-use antimicrobial agents bearing α-dicarbonyl groups is suggested by the findings of this study.