National Survey of Youth in Custody, 2008-2009

Response Rates: Calculating facility-level response rates Within each facility a base weight was created for each youth in the sexual victimization survey by taking the inverse of each youth's probability of selection. In most facilities youth selection probabilities were the same. However, in some sampled facilities (e.g. where females were oversampled and where rosters contained duplicate records) selection probabilities varied. An initial facility response rate was calculated by summing the base weights for all youth completing the sexual victimization survey and dividing it by the sum of the base weights for all sampled youth (minus ineligible youth) in each facility. A final response rate was calculated to account for the deletion of interviews containing extreme or inconsistent responses. This was achieved by multiplying the initial facility response rate by an adjustment ratio. In each facility this ratio represented the sum of final weights for all interviewed youth excluding those with extreme or inconsistent responses divided by the sum of final weights for all interviewed youth including those with extreme or inconsistent responses. This final adjusted response rate was then multiplied by 100. Calculations for Mt. Meigs Campus (Alabama) illustrate the calculation of these weighted facility-level response rates. The facility listed 278 youth on its roster. Of these listed, 193 were subsampled. Thirteen of the sampled youth were roster errors (and were excluded from the sample). Of the remaining 180 sampled youth, 32 were discharged prior to the visit, leaving 132 sampled for the sexual victimization survey and 16 for supplemental survey. Of the 132 eligible youth, 121 completed the NSYC survey. After adjusting for the probability of selection for each youth, the 121 youth who completed the sexual victimization survey represented 208 youth (or 91.7 percent of the 227 eligible youth in the facility). Three of the youth provided extreme or three or more inconsistent responses and were excluded. After adjusting for the probability of selection for each youth, a ratio adjustment of .974 was applied to the initial response rate, resulting in an overall facility response rate of 89.3 percent (.974 times .917 times 100 percent).