Table 1

Concepts and search items

Databases	Search items
MEDLINE ISI of Knowledge CENTRAL EMBASE SCOPUS LILACS PsycINFO CNKI	#1 ((‘Young’ (All Fields) OR ‘Young Adult’ (MeSH Terms) OR ‘Adult’ (MeSH terms))) #2 ((‘Coronavirus’ (MeSH terms) OR ‘Coronavirus’ (all fields)) OR (‘COVID-19’ (all fields) OR ‘Severe Acute Respiratory Syndrome Coronavirus 2’ (supplementary concept) OR ‘Severe Acute Respiratory Syndrome Coronavirus 2’ (all fields) OR ‘2019-nCoV’ (all fields) OR ‘SARS-CoV-2’ (all fields)) OR ‘Pandemics’ (MeSH terms)) #3 ((‘Mental Health’ (MeSH terms) OR (‘Mental’ (all fields) AND ‘Health’ (all fields)) OR ‘Mental Health’ (all fields)) OR (‘Mental Disorders’ (MeSH terms) OR (‘Mental’ (all fields) AND ‘Disorders’ (all fields)) OR ‘Mental Disorders’ (all fields)) OR ‘Mental Illness’ (all fields) OR ‘Psychological Distress’ (MeSH terms) OR ‘Distress, Psychological’ (all fields) OR ‘Emotional Distress’ (all fields) OR ‘Distress, Emotional’ (all fields)) #4 #1 AND #2 AND #3

Databases

Search items

MEDLINE
ISI of Knowledge
CENTRAL
EMBASE
SCOPUS
LILACS
PsycINFO
CNKI

#1 ((‘Young’ (All Fields) OR ‘Young Adult’ (MeSH Terms) OR ‘Adult’ (MeSH terms)))
#2 ((‘Coronavirus’ (MeSH terms) OR ‘Coronavirus’ (all fields)) OR (‘COVID-19’ (all fields) OR ‘Severe Acute Respiratory Syndrome Coronavirus 2’ (supplementary concept) OR ‘Severe Acute Respiratory Syndrome Coronavirus 2’ (all fields) OR ‘2019-nCoV’ (all fields) OR ‘SARS-CoV-2’ (all fields)) OR ‘Pandemics’ (MeSH terms))
#3 ((‘Mental Health’ (MeSH terms) OR (‘Mental’ (all fields) AND ‘Health’ (all fields)) OR ‘Mental Health’ (all fields)) OR (‘Mental Disorders’ (MeSH terms) OR (‘Mental’ (all fields) AND ‘Disorders’ (all fields)) OR ‘Mental Disorders’ (all fields)) OR ‘Mental Illness’ (all fields) OR ‘Psychological Distress’ (MeSH terms) OR ‘Distress, Psychological’ (all fields) OR ‘Emotional Distress’ (all fields) OR ‘Distress, Emotional’ (all fields))
#4 #1 AND #2 AND #3

MEDLINE, Medical Literature Analysis and Retrieval System Online; CENTRAL, Cochrane Central Register of Controlled Trials; EMBASE, Excerpta Medica Database; LILACS, Latin American and Caribbean Health Sciences Literature; PsycINFO, Psychology Information; CNKI, Chinese National Knowledge Infrastructure.