This review aims to provide a comprehensive synthesis and determine pooled effectiveness of nutritional interventions on the nutritional status of undernourished children ages 0-5 years old in low- and middle-income countries. This review included Randomized Controlled Trials, Pre-post Interventional, Case-Control, and Cohort Studies that were conducted from 2016-to 2019. The search and identification of literature, supplemented with the inclusion and exclusion criteria, was done through an online database (Pubmed, Ebscohost, ScienceDirect, and Google Scholar) and in the Ateneo de Zamboanga, School of Medicine Library. This study utilized four tools of appraisal: Risk of Bias-2 for Randomized Controlled Trials (RCTs), Risk of Bias in Non-Randomized Studies- of Interventions for Non-Randomized Studies (NRSI), and Heller’s Public Health Checklist for ADZU SOM’s quasi-experimental (within-group) designs. Out of thirty-one (31) studies, this review compiled seven (7) interventions: local and homemade food, nutritional education, food production, milk-based formula, reduced dose of RUTF, rehabilitation programs, and positive deviance approach. This review found that local and homemade food improves the nutritional status of undernourished children below five years old. Findings show that nutrition education has little to no effect, while food production needs more studies to increase its certainty. Other interventions mentioned need more similar studies to obtain a pooled effectiveness. This review has excluded studies that are of high risk of bias to minimize low certainty of evidence. However, this review was unable to examine the adverse effects of the interventions. This review has some studies not pooled due to missing values such as standard deviations and confidence intervals.

Keyword: Nutritional status of undernourished children