The actual rate of non-paternity in western societies is closer to 3%. The 10-20% figures that appear regularly on the internet are largely derived from rates o

The actual rate of non-paternity in western societies is closer to 3%. The 10-20% figures that appear regularly on the internet are largely derived from rates of non-paternity in cases were paternity was questioned (i.e. pre-existing suspicions of infidelity). The higher ranges quoted (30% is the highest I have seen) are generally from small study populations with extended periods of partner absence, like central American itinerant laborers or African truck drivers.