The NCS-2 sought to trace and re-interview all Part II NCS respondents a decade after the NCS. Of the 5463 respondents successfully traced, 166 were deceased and 5001 re-interviewed, for a conditional response rate of 87.6%. The unconditional response rate is 72.2% (0.876 × 0.824). NCS-2 respondents were assessed using an expanded version of the baseline interview that assessed onset and course of disorders between the two surveys. Relative to other baseline NCS respondents, NCS-2 respondents were significantly more likely to be female, well educated, and residents of rural areas. A propensity score adjustment weight30 corrected for these discrepancies. Importantly, there was no difference between NCS-2 respondents and non-respondents in their reports of SROs at the baseline assessment.31
