Prevalence of underweight in Iranian children: a systematic review and meta-analysis

Background: Children's health, preserving and promoting it is a health priority of any society. Malnutrition affects all age groups, but malnutrition in children is one of the most common nutritional problems that can delay body growth, shortened height, frequent infections, mental retardation, the prevalence of mental disorders, lack of academic achievement and reduced efficacy. Because of the importance and impact of this issue in children, the purpose of this study was a systematic review and meta-analysis of the prevalence of underweight in Iranian children, in order to highlight the importance of this issue to health policy-makers. Methods: A meta-analysis was performed for relevant articles in scientific databases including Scientific Information Database (SID), ScienceDirect, PubMed and Google Scholar. Entrance criteria included cross-sectional studies (March 1996 to February 2017) that had a low incidence of underweight in Iranian children in different parts of Iran. Non-relevant articles included review articles, interventions, cohorts and case studies, and studies that looked at obesity, overweight and the relationship between these factors and other diseases, excluded from the study list. Reference lists of identified articles were reviewed for additional articles. Heterogeneity of study was checked using I2 index and the possibility of publication bias by funnel plot and Begg and Mazumdar's rank correlation test and a significance level of 0.1. Data were analyzed using the comprehensive meta-analysis software, version 3 (Biostat, Englewood, NJ, USA). Results: In 26 articles reviewed in the study, total number of participants was 142938  persons at the age of 1 month to 12 years. The overall prevalence of underweight in Iranian children was 15.5% (Cl 95%: 12%-19.7%) during 1996 to 2017. The highest prevalence of underweight in was recorded in Birjand city in 2006 and Zahedan city in 2009, 68.6% (Cl 95%: 63.3%-72.9%) and the lowest prevalence of underweight in was found in city of Jahrom in 2013, 1.8% (Cl 95%: 1.2%-2.9%). Conclusion: According to the results of this study, the prevalence of low-birth-weight in the country is high and requires interventional measures