Table 1.

A Summary of the Inclusion and Exclusion Criteria Based on the PEO Format

PEO Strategy	Inclusion	Exclusion
Population	Cross-sectional studies, case-control studies and prospective and retrospective cohort studies; full test publications; studies published in English; reported effect size (odds ratio OR, hazard ratio HR, risk ratio RR with confidence intervals CIs) of the relationship between CM in childhood and MetS in adulthood. Agency reports, self-reports, interviews, and agency records in studies using any CM measurement; human studies and published in English.	Abstracts, Case reports, duplicate studies, editorials, reviews, grey literature, commentary, conference papers and books; studies not published in English; non-human studies.
Exposure	The exposure was CM, including type (physical abuse, emotional/psychological, sexual abuse and neglect) or number (one or more) of maltreatment and comparison made with individuals who did not experience CM; maltreatment happened before the age of 18 years.	Maltreatment occurred after the age of 18 years; neither physical, sexual, emotional/psychological abuse nor neglect; maltreatment happened after the age of 18 years.
Outcome	MetS as an outcome; a measure of MetS as defined by either WHO, NCEP or IDF; MetS occurred after age 18. Diagnosis of MetS was based on medical records. MetS happened after the age of 18 years.	The measure of MetS is not defined by eitherWHO, NCEP, or IDF. The diagnosis of MetS is not based on medical records; MetS occurs before the age of 18.

Abbreviations: IDF, International Diabetes Federation; NCEP, National Cholesterol Education Program; WHO, World Health Organisation.