Dubious SHS Statistics

Here's the relevant part of Gio Batta Gori's recent Washington Post essay on the dubious methodology behind the determination of secondhand smoke death statistics:

Typically, the studies asked 60–70-year-old self-declared nonsmokers to recall how many cigarettes, cigars or pipes might have been smoked in their presence during their lifetimes, how thick the smoke might have been in the rooms, whether the windows were open, and similar vagaries. Obtained mostly during brief phone interviews, answers were then recorded as precise measures of lifetime individual exposures.

In reality, it is impossible to summarize accurately from momentary and vague recalls, and with an absurd expectation of precision, the total exposure to secondhand smoke over more than a half-century of a person's lifetime. No measure of cumulative lifetime secondhand smoke exposure was ever possible, so the epidemiologic studies estimated risk based not only on an improper marker of exposure, but also on exposure data that are illusory.

Don't get me wrong. Secondhand smoke can be dangerous, especially if breathed in large quantities over long period of time. But there is some great doubt about putting precise statistics behind it.