bb Mastrangelo 2000.

Methods	Case‐control study assessing the association between influenza vaccines and cutaneous melanoma
Participants	99 cases and 104 controls
Interventions	Influenza vaccine exposure is not described.
Outcomes
Notes	The authors report a protective effect of repeated influenza vaccination on the risk cutaneous melanoma (OR 0.43, 95% CI 0.19 to 1.00). The study is at high risk of bias due to the selective nature of cases (all patients in the authors' hospital), attrition bias (4 cases and 4 controls eliminated because of "failure to collaborate"), recall bias (up to 5 years' exposure data were based on patients' recollection), and ascertainment bias (non‐blinded exposure survey). Rare events (safety) Government funded
Risk of bias
Bias	Authors' judgement	Support for judgement
CC ‐ case selection All outcomes	Low risk	Low
CC ‐ control selection All outcomes	Unclear risk	Insufficient information
CC ‐ comparability All outcomes	Unclear risk	Insufficient information
CC ‐ exposure All outcomes	Low risk	Low
Summary assessment	Unclear risk	Unclear