Table 1.

Human and animal PECO (population, exposure, comparator, outcome) statements.

PECO element	Human evidence	Animal evidence
Study question	Does developmental exposure to PFOA affect fetal growth in humans?	Does developmental exposure to PFOA affect fetal growth in animals?
Participants	Humans that are studied during the reproductive/developmental time period (before and/or during pregnancy or development)	Animals from non­human species that are studied during the reproductive/developmental time period (before and/or during pregnancy for females or during development for embryos)
Exposure	Exposure to PFOA (CAS# 335-67-1) or its salts during the time before pregnancy and/or during pregnancy for females or directly to fetuses	One or more oral, subcutaneous, or other treatment(s) of any dosage of PFOA (CAS# 335-67-1) or its salts during the time before pregnancy and/or during pregnancy for females or directly to embryos
Comparators	Humans exposed to lower levels of PFOA than the more highly exposed humans	Experimental animals receiving different doses of PFOA or vehicle-only treatment
Outcomes	Effects on fetal growth, birth weight, and/or other measures of size, such as length	Changes in fetal weight near term (e.g., embryonic day 18 for mice, embryonic day 21 for rats), birth weight, and/or other measures of size at term or birth, such as length