Table 1 Application of PICOS criteria for study inclusion

Participants

Inclusion criteria:

1)  ≥ 18 years adults

2) With or without cancer

Exclusion criteria:

1) Have any mental disorders

2) Whose blood sample cannot be got for any reason, etc.

Intervention/exposure

Patients with cancer or patients with high level SFA

Comparison

Patients without cancer or patients with low level SFA

Outcome

A dichotomous outcome: cancer or no cancer diagnosis. (can be overall or site-specific cancer)

Study design

Observational study, mainly case-control and cohort. Only human studies were considered, no animal studies