addition to the case families, a set of families, called “comparison” families, were recruited from a variety of community sources (e.g., dental clinic admissions and state drivers' registries) and assessed with the identical expanded protocol. Extensions to other family branches in the comparison families were also allowed as described above, although this was a rare occurrence. For the comparison families, there had to be two living parents and 3 (or more) children aged 14 or older. The presence of AUDs in the comparison families was not used as an exclusion criterion.
