Abbreviations, acronyms & symbols
6MWT	= Six-minute walk test
ATS	= American Thoracic Society
FAPITEC/SE	= Fundação de Apoio à Pesquisa e à Inovação
	Tecnológica do Estado de Sergipe, Brasil
IBECS	= Spanish Bibliographic Index on Health Sciences
LILACS	= Latin American and Caribbean Health Sciences
PAHO	= Collection of the Pan American Health Organization
PRISMA	= Preferred Reporting Items for Systematic Reviews
	and Meta-Analyses
SciELO	= Scientific Electronic Library Online
VHL	= Virtual Health Library
WHO	= World Health Organization