Table 1 Inclusion and exclusion criteria

Population

Aged ≥ 18 years

Underwent surgery (all surgical settings including elective/emergency/major or minor surgeries or procedures)

Used a valid frailty measure and majority of the sample classified as frail.

Aged < 18 years

Did not undergo surgery

Did not use a valid frailty measure.

Used a valid frailty measure but majority of the sample not classified as frail or data for frail group unable to be extracted.

Intervention

Perioperative multicomponent intervention

Interventions targeting a single health domain

Interventions forming part of established standard of care protocols, such as ERAS.

Comparator

Standard/usual care

Alternative intervention (superiority trial)

Outcome

Examined relationship between intervention/comparator and one or more outcome(s)

Study design

Randomised controlled trials, quasi-experimental studies

Observational studies

Publication Criteria

Published and “in press” articles reporting original research results

Conference abstract only, reviews, book chapters, editorials, theses

Full text not available

Language

Studies written in English