Abstract: Four studies (187 children) met the inclusion criteria. Three studies were carried out in children with cystic fibrosis and one study included children with paediatric malignant disease. Overall there was a low risk of bias for blinding and incomplete outcome data.Two studies had a high risk of bias for allocation concealment. Few statistical differences were found in the outcomes we assessed between treatment and control groups, except change in total energy intake at six and 12 months, mean difference 304.86 kcal per day (95% confidence interval 5.62 to 604.10) and mean difference 265.70 kcal per day (95% confidence interval 42.94 to 485.46), respectively. However, these were based on the analysis of just 58 children in only one study. Only two chronic diseases were included in these analyses, cystic fibrosis and paediatric malignant disease. No other studies were identified which assessed the effectiveness of oral protein calorie supplements in children with other chronic diseases. Oral protein calorie supplements are widely used to improve the nutritional status of children with a number of chronic diseases. We identified a small number of studies assessing these products in children with cystic fibrosis and paediatric malignant disease, but were unable to draw any conclusions based on the limited data extracted. We recommend a series of large, randomised controlled trials be undertaken investigating the use of these products in children with different chronic diseases. Until further data are available, we suggest these products are used with caution.

Plain-language summary: We looked for trials of oral protein calorie supplements compared to usual treatment or no alternative treatment where the children took the supplements for at least one month. The review included four trials with 187 children; in three of these the children had cystic fibrosis and in one they had cancer. Studies lasted from three months to one year. We recorded the results and judged whether the trials were at risk of being biased based on the design or the way it was run. We looked at outcomes such as weight and height, calorie intake, behaviour and also side effects. One study (with 58 children) showed increases in the total calories consumed at both six and 12 months. None of the other outcomes we looked at showed any difference between treatments. This is an updated version of the review, which found no conclusive evidence to support the use of oral protein supplements. We suggest that at least one high quality trial be conducted.Therefore, we suggest that these products are used sparingly and with caution. Overall the included studies had a low risk of bias, except for two studies in which it was possible that the organisers knew which treatment group in which the children would be placed. These issues are unlikely to change the results as knowing which treatment one receives is unlikely to affect the results of body measurements (e.g. weight, height outcomes). All planned outcomes were reported on, with the exception of one study that did not report on eating behaviour and lipase intake which were measured. The quality of the results for the eating behaviour assessment was questionable and many of the children did not return the food diaries from which the lipase intake could be calculated.