Collateral Interviews
Interviews with collateral informants (parent, family member or friend) were also completed at the time of the baseline interview and annually for the first three years of follow-up
- At baseline, the collateral informant was usually a parent (in order to provide rich background information regarding the study participant)
- A follow-up, the collateral informant was usually a peer (in order to provide more accurate information about deviant behavior)
We have a collateral report for 89% of the subjects at the baseline interview. At the baseline interview, 69% of the collateral reporters are a mother, 12% a father, 7% a grandparent, 4% a sibling and 7% some "other" relative or friend.
At the 12-month interview we have a collateral report for 89% of the completed subject interviews (83% of 1,354). At this wave, 56% of the collateral reporters are a peer/friend, 22% a sibling, 15.5% a parent, 2% a grandparent and 4% "other".
At 24 months we have a collateral report for 91% of the completed subject interviews (83% of the 1,354). 53% of these collateral reporters are a peer/friend, 20% are a sibling, 20% are a parent, 3% are a grandparent and 4% "other".
Finally, at 36 months we have a collateral report for 93% of the completed subject interviews (85% of the 1,354) with 54% of those reporters a peer/friend, 17% a sibling, 22% a parent, 3% a grandparent and 4% "other".
Collateral interviews are discontinued at the point where we shift to annual subject interviews (after 36-months) because the cost becomes prohibitive and the value of this information declines.
Baseline Collateral Reference List