Increased portion size leads to a sustained increase in energy intake over 4 d in normal-weight and overweight men and women.

Large food portions may be facilitating excess energy intake (EI) and adiposity among adults. The present study aimed to assess the extent to which EI and amounts of foods consumed are influenced by the availability of different-sized food portions. A randomised within-subject cross-over, fully residential design was used, where forty-three (twenty-one men and twenty-two women) normal-weight and overweight adults were randomly allocated to two separate 4 d periods where they were presented with either 'standard' or 'large' food portions of the same foods and beverages. The main outcome measures were the amount of food (g) and EI (MJ) consumed throughout each study period. Mean EI over 4 d was significantly higher on the large portion condition compared with the standard condition in the total group (59.1 (sd 6.6) v. 52.2 (sd 14.3) MJ; P = 0.020); men and women increased their EI by 17 % (10 (sd 6.5) MJ; P < 0.001) and 10 % (4 (sd 6.5) MJ; P = 0.005) respectively when served the large food portions relative to the standard food portions. The increased intakes were sustained over the 4 d in the large portion condition with little evidence of down-regulation of EI and food intake being made by subjects. Increased food portion size resulted in significant and sustained increases in EI in men and women over 4 d under fully residential conditions. The availability and consumption of larger portions of food may be a significant factor contributing to excess EI and adiposity.

What is a 'generic' hospital model?--a comparison of 'generic' and 'specific' hospital models of emergency patient flows.

The paper addresses the question in the title via a survey of experienced healthcare modellers and an extensive literature review. It has two objectives. 1. To compare the characteristics of 'generic' and 'specific' models and their success in hospitals for emergency patients 2. To learn lessons about the design, validation and implementation of models of flows of emergency patients through acute hospitals First the survey and some key papers lead to a proposed 'spectrum of genericity', consisting of four levels. We focus on two of these levels, distinguished from each other by their purpose. Secondly modelling work on the flow of emergency patient flows through and between A&E, Bed Management, Surgery, Intensive Care and Diagnostics is then reviewed. Finally the review is used to provide a much more comprehensive comparison of'generic' and 'specific' models, distinguishing three types of genericity and identifying 24 important features of models and the associated modelling process. Many features are common across model types, but there are also important distinctions, with implications for model development.