Table 2.

Inclusion and exclusion criteria.

Criterion	Inclusion	Exclusion
Age limit	Seniors aged 60 years and above	Children and Adults younger than 60 years
Population	Community-dwelling seniors	Institutionalized seniors
Study design	All study designs	Cross-sectional studies and commentaries
Association of interest	Poor oral health (exposure) and a broad range of outcomes including general health, Quality of life, mortality, etc.	Studies measuring the association in a reverse direction, or studies that are not relevant to the study scope
Time limit	January 2000 up to May 2019	Studies prior to 2000
Language	English	Non-English
Study location	OECD* countries	Non-OECD countries

^*Organization for Economic Co-operation and Development.