Measures of nutrition intake and growth reported in preterm nutrition studies: A scoping review

There are inconsistent recommendations in available guidelines and uncertainty regarding the exact nutrient requirements for preterm infants, partly because of inconsistent outcome reporting in nutrition intervention studies. To support development of a minimum reporting set, we undertook a scoping review to identify measures of nutrition intake and growth outcomes reported in recent preterm nutrition studies. We searched for publications from 2018 to 2023 reporting individuals born preterm at any gestational age and study location whose nutrition intake was assessed before first hospital discharge and whose growth was assessed at any age. One reviewer screened articles and extracted the measures. Any uncertainties were resolved by a second reviewer. The results were tabulated and analyzed descriptively. We identified 6365 records, and included 250 studies. Only 10 of 236 studies (4%) reported how nutrition intake was calculated. There were five different ways of reporting weight and 13 of weight gain, each at many different time points. Furthermore, 27 of 105 studies (26%) did not report how weight gain was calculated, and those that did reported five different calculation methods. Our findings demonstrate significant variation and incomplete reporting of nutrition intake and growth outcomes in preterm nutrition studies. This lack of standardization limits the utility of existing evidence and highlights the need for a standardized reporting framework to improve comparability and support evidence-based guidelines in preterm nutrition.