TABLE 4.

Overview of the main characteristics and necessary data for source attribution methods.

	Point of attribution				Pathogen data		Human data			Source data
Method	Reservoir∗	Exposure	Transmission route	Risk factor	Subtyping	Fitness	Subtyping	Sporadic or epidemic status	Exposure & risk factors∗∗	Subtyping	Prevalence and exposure∗∗∗	Need to consider all potential sources
Epidemiological (case-control study)	No	Yes	Yes	Yes	No	No	No	Sporadic	Yes	No	No	High
Epidemiological (outbreak investigation)	No	Yes	Yes	Yes	No	No	No‡	Epidemic	Yes	No	No	High
Microbiological (frequency-matching models)	Yes	Yes	Yes	No	Yes	No‡	Yes	Sporadic and epidemic	No‡	Yes	Yes	Medium
Microbiological (population genetics models)	Yes	Yes	Yes	No	Yes	No	Yes	Sporadic or epidemic	No	Yes	No	High
Quantitative exposure/risk assessment	Yes	Yes	Yes	Yes	No	Yes	No	N/A	Yes	No	Yes	Medium
Expert elicitations	Yes	Yes	Yes	Yes	No	No	No	Sporadic or Epidemic	No	No	No	Low

N/A, not applicable. ^∗Or amplifying hosts. ^∗∗Including travel status. ^∗∗∗In this case, food consumption weights. ^‡But can be used if available.