Abdulkadir et al. (2016)
Reason for exclusion	Study conducted in a high income country (UK)
Abrahamse‐Berkeveld et al. (2016)
Reason for exclusion	Study conducted in a high income country (Germany and Italy)
Abrahamsson et al. (2005)
Reason for exclusion	No relevant outcomes were found
ADAPTS trial (2019)
Reason for exclusion	Wrong settings: Ongoing study in Australia
Agarwal et al. (2003)
Reason for exclusion	No relevant clinical outcomes were reported
Agarwal (2018)
Reason for exclusion	Study conducted in a high income country (Australia)
Ahmadipour et al. (2019)
Reason for exclusion	Study conducted to treat neonatal Jaundice.
Ahmadpour Kacho et al. (2005)
Reason for exclusion	No relevant outcomes were reported
Al‐Hosni et al. (2012)
Reason for exclusion	Study conducted in a high income country (USA)
Ala‐Houhala et al.(1988)
Reason for exclusion	Study conducted in a high income country (Finland)
Allen et al. (2010)
Reason for exclusion	Study conducted in high income country (UK)
Armanian et al. (2014)
Reason for exclusion	Study participants were given only Prebiotics and no probiotics
Arthur et al. (1992)
Reason for exclusion	Study population did not include Neonates
Aryayev et al. (2018)
Reason for exclusion	Study conducted in high income country
Athalye‐Jape et al. (2018)
Reason for exclusion	Study conducted in high income country
Awad et al. (2010)
Reason for exclusion	Study was retracted
Ayah et al. (2007)
Reason for exclusion	Vitamin A was given at 14 weeks
Aydin et al. (2012)
Reason for exclusion	Population included children with Congential Heart disease only
Baglatzi et al. (2016)
Reason for exclusion	Study conducted in a high income country
Bakker (2005)
Reason for exclusion	Study continued supplementation of probiotics for 4 months
Bakker Zierikzee (2005)
Reason for exclusion	Study conducted in a high income country (Netherland)
Bin‐Nun et al. (2005)
Reason for exclusion	Study conducted in Israel
Bocquet et al. (2013)
Reason for exclusion	Study conducted in a high income country (France)
Bonati (1993a)
Reason for exclusion	Study conducted in a high income country (Italy)
Bonati (1996b)
Reason for exclusion	Study conducted in a high income country (Italy)
Bora & Deori (2019)
Reason for exclusion	Study compared two forms of the same intervention
Cekola et al. (2015)
Reason for exclusion	Study conducted in a high income country (USA)
Chabra et al. (2013)
Reason for exclusion	Study conducted in a high income country (USA)
Chandel et al. (2017)
Reason for exclusion	No relevant clinical outcomes were available
Chi (2019)
Reason for exclusion	No clinical outcomes were available
Chouraqui et al. (2008)
Reason for exclusion	Study conducted in a high income country (France)
Chrzanowska‐Liszewska (2011)
Reason for exclusion	Study conducted in a high income country (Poland)
Chua et al. (2017)
Reason for exclusion	Study conducted in a high income country (Netherland)
Corkins & Kovacevich (2001)
Reason for exclusion	Study conducted UK
Costalos et al. (2003)
Reason for exclusion	Study conducted in a high income country (Greece)
Costeloe (2016)
Reason for exclusion	Study conducted in a high income country (UK)
Coutsoudis et al. (1996)
Reason for exclusion	No clinical outcomes were available
Dani et al. (2002)
Reason for exclusion	Study conducted in high income country (
Darboe et al. (2007)
Reason for exclusion	Study conducted on wrong study population (infants)
Delimont et al. (2019)
Reason for exclusion	Study conducted on older children and used Sorghum‐Based and Corn‐Based Fortified Blended Foods
Delvin et al. (2000)
Reason for exclusion	Study conducted in a high income country (US)
Deng & Chen (2010)
Reason for exclusion	No abstract or full text available and no relevant outcomes were available.
Denkel et al. (2017)
Reason for exclusion	Study conducted in a high income country (Germany)
Deshpande 2016
Reason for exclusion	Study conducted in high income country
Diaby et al. (2018)
Reason for exclusion	Observational study assessing the coverage of vitamin A supplementation
Dilli et al. (2013)
Reason for exclusion	Study conducted on wrong patient population (infants with congenital heart diseases)
Elom et al. (2019)
Reason for exclusion	Wrong study population
Escribano et al. (2018)
Reason for exclusion	Study conducted in a high income country (Spain)
Galderisi et al. (2016)
Reason for exclusion	The study investigated glucose monitoring and not the dextrose gel
Garg et al. (2017)
Reason for exclusion	Wrong study design (retrospective cohort study)
Garland et al. (2011)
Reason for exclusion	Study conducted in a high income country (Australia)
Garofoli et al. (2018)
Reason for exclusion	Wrong setting
Gomber (1996)
Reason for exclusion	Wrong study design
Gomez‐Rodriguez et al. (2019)
Reason for exclusion	Compared two different regimens of probiotics. No placebo group was included.
Gonchar et al. (2016)
Reason for exclusion	No relevant outcomes were available. Study only available in the form of abstract. Authors were contacted for full text but no response
Guo‐Qiang et al. (2016)
Reason for exclusion	Wrong study design
Hammerman & Bin‐nun (2007)
Reason for exclusion	Wrong intervention
Harris et al. (2016)
Reason for exclusion	Study conducted in New Zealand
Hays (2015)
Reason for exclusion	Study conducted in a high income country
Hoy‐Schulz et al. (2016)
Reason for exclusion	Study conducted on wrong patient population
Hoyos (1999)
Reason for exclusion	Wrong study design
Hua et al. (2014)
Reason for exclusion	Only abstract available and no relevant clinical outcomes were available
Huang et al. (2016)
Reason for exclusion	No relevant outcomes were available
Hunter et al. (2012)
Reason for exclusion	Wrong study design
Härtel (2019)
Reason for exclusion	The study is being conducted in a high income country (Germany)
Idindili et al. (2007)
Reason for exclusion	Study conducted on wrong patient population
Indrio et al. (2008)
Reason for exclusion	Study conducted in a high income country
IRCT (2015)
Reason for exclusion	Wrong comparison
Jacobs (2017)
Reason for exclusion	Study conducted in a high income country
Janvier et al. (2014)
Reason for exclusion	Study conducted in a high income country
Kahbazi et al. (2019)
Reason for exclusion	Wrong study population
Kanic et al. (2015)
Reason for exclusion	Study conducted in a high income country
Karthikeyan & Bhat (2017)
Reason for exclusion	Study conducted in a high income country
Kiatchoosakun (2014)
Reason for exclusion	No relevant outcomes were available
Kirkwood et al. (2010)
Reason for exclusion	Wrong study design
Kliegman (2005)
Reason for exclusion	Wrong study design
Koksal et al. (2015)
Reason for exclusion	Only abstract was available and no analyzable data were reported
Kukkonen et al. (2008)
Reason for exclusion	Wrong study design
Leele et al. (2015)
Reason for exclusion	Study conducted in a high income country (Singapore)
Li (2019)
Reason for exclusion	The intervention continued for 4 months
Lin (2009)
Reason for exclusion	Study conducted in a high income country (Taiwan)
Long & Dempsey (2018)
Reason for exclusion	Study conducted in a developed country
Lozano (2008)
Reason for exclusion	Study conducted in a high income country
Lund et al. (2014)
Reason for exclusion	The control group did not receive the placebo but polio vaccine. It is difficult to tease out the effect of vitamin A supplementation vs. No vitamin A supplementation.
Lundelin et al. (2017)
Reason for exclusion	Study conducted in a high income country
Mactier et al. (2012)
Reason for exclusion	Study conducted in a high income country
Maldonado‐Lobon (2015)
Reason for exclusion	Study conducted in a high income country
Manzano et al. (2017)
Reason for exclusion	Study conducted in a high income country (Spain)
Manzoni et al. (2006)
Reason for exclusion	Study conducted in a high income country (Italy)
Manzoni et al. (2009)
Reason for exclusion	Study conducted in a high income country (italy)
Marissen et al. (2019)
Reason for exclusion	This is an ongoing study in Germany which is a high income country.
Martins et al. (2009)
Reason for exclusion	Wrong study population
Materna (2010)
Reason for exclusion	Study conducted in a high income country
McCulloch et al. (2012)
Reason for exclusion	Study conducted in a high income country (UK)
McKinlay (2016)
Reason for exclusion	Study conducted in a high income country
Meyer & Gortner (2014)
Reason for exclusion	Study conducted in a high income country (Germany)
Mg (2011)
Reason for exclusion	Study conducted in a high income country (Italy)
Mihatsch et al. (2010)
Reason for exclusion	Study conducted in a high income country (Germany)
Millar (2017)
Reason for exclusion	Study conducted in a high income country
Moles et al. (2015)
Reason for exclusion	Study conducted in high income country
Nadella et al. (2019)
Reason for exclusion	Wrong intervention
Nct (2006)
Reason for exclusion	Study conducted in high income country
Nct (2016)
Reason for exclusion	Wrong settings
Papagaroufalis et al. (1991)
Reason for exclusion	Study conducted in high income country (Greece)
Papagaroufalis et al. (2014)
Reason for exclusion	Study conducted in high income country (Greece)
Patole et al. (2016)
Reason for exclusion	Study conducted in a high income country (Australia)
Pearson et al. (1992)
Reason for exclusion	Study conducted in a high income country (USA)
Plummer et al. (2018)
Reason for exclusion	Study conducted in a high income country (Australia)
Puccio et al. (2007)
Reason for exclusion	Study conducted in a high income country (Italy)
Qiao et al. (2017)
Reason for exclusion	No relevant outcomes were available
Radke et al. (2017)
Reason for exclusion	Study conducted in a high income country (Germany)
Raguž et al. (2016)
Reason for exclusion	Wrong study design
Rakshasbhuvankar et al. (2017)
Reason for exclusion	Study conducted in a high income country (Australia)
Rawat et al. (2016)
Reason for exclusion	Study conducted in the USA
Repa et al. (2015)
Reason for exclusion	Study conducted in a high income country (Austria)
Robbins & Fletcher (1993)
Reason for exclusion	wrong comparator
Rodriguez‐Herrera et al. (2019)
Reason for exclusion	Study conducted in a high income country
Rodríguez (2015)
Reason for exclusion	Study compared two forms of Probiotics and no comparison with placebo was available
Rohan (2016)
Reason for exclusion	Study conducted in a high income country (UK)
Ross et al. (1993)
Reason for exclusion	Study included children 6 months and older
Rouge et al. (2009)
Reason for exclusion	Study conducted in a high income country (France)
Rubaltelli et al. (2000)
Reason for exclusion	Study conducted in a high income country (Italy)
Sadowska‐Krawczenko et al. (2012)
Reason for exclusion	Study conducted in a high income country (Germany)
Samuels et al. (2016)
Reason for exclusion	Study conducted in a high income country (Netherland)
Shenai et al. (1987)
Reason for exclusion	Study conducted in a high income country (USA)
Smilowitz et al. (2017)
Reason for exclusion	Study conducted in a high income country (USA)
Storm et al. (2019)
Reason for exclusion	Study conducted in a high income country USA
Stratiki et al. (2007)
Reason for exclusion	Study conducted in a high income country (Greece)
Strus et al. (2018)
Reason for exclusion	Study conducted in a high income country (Poland)
Ter (2017)
Reason for exclusion	Study conducted in Australia
Thanhaeuser et al. (2014)
Reason for exclusion	Study conducted in a high income country (Austria)
Totsu et al. (2014)
Reason for exclusion	Study conducted in a high income country (Japan)
Tyson et al. (1999)
Reason for exclusion	Study conducted in a high income country (USA)
Venkatarao et al. (1996)
Reason for exclusion	Infant received vitamin A at 6 months
Vlieger et al. (2009)
Reason for exclusion	Study conducted in high income country (Netherland)
Wardle et al. (2001)
Reason for exclusion	Study conducted in high income country (UK)
West et al. (1991)
Reason for exclusion	Study included children 6‐59 months of age
Yang et al. (2011)
Reason for exclusion	Full text not available and no abstract was available either so no relevant outcomes were available.