Validity of digital photography as a means of assessing dietary intake in post-operative colorectal surgery patients who are following the enhanced recovery after surgery (ERAS) protocol.

Introduction: Dietary assessment tools (e.g. 24-hour recall, diet diaries, food record charts, food frequency questionnaires, weighed food records) are widely used in acute, community and research settings to estimate the nutritional intake of service-users and/ or research participants. The outcome of dietary assessment directly impacts patient care plans therefore accurate and reliable assessment methods are needed. Utilising technology such as digital photography can help to improve dietary assessment in various settings. Aim: The primary goal of the study was to determine if digital photography can be used as a method of dietary assessment in the clinical setting. Methods and Materials: Lunch and evening meals were selected for analysis from a convenience sample of patients participating in a wider study on the colorectal surgery unit at the Western General Hospital, Edinburgh. The digital photography method was compared to the weighed intake as a reference. Soups and main courses were included in the data collection. Digital photographs were taken before and after the meals were served to the patients and any left-overs were weighed. The photographs were analysed to ascertain weight provision and left-overs using a photo atlas whilst the provision weights for the weighed intake for each meal were determined from a database of standard NHS Lothian recipes on the dietary analysis programme, Nutmeg. The provision and left-over of energy and protein in the photographs and the weighed intake were calculated from the nutrient analysis per 100g for each recipe on Nutmeg. Results: There was no significant difference between the two methods (p=>0.05) for both soups and main courses for provision and left-over weight, energy and protein. Overall, limits of agreement for soup were more acceptable (within + 1.96 SD) than main courses for provision and left-over weight, energy and protein. Conclusion: Digital photography is a feasible method of dietary assessment in the clinical setting. The results out with the limits of agreement can be explained by the differences between the 'standard recipes' on Nutmeg and those recipes and portion sizes served to patients. Key words: Digital photography; Diet; Assessment; Weighed intake; Clinical setting; Enhanced recovery after surgery (ERAS)bsc_dietunpub2161_ethesesunpu