The conduct problems could be measured via an adaptation of a questionnaire by Odgers, Moffitt, Broadbent, et al. (2008) that asked (yes/no) whether youths engaged in problematic behaviors such as stealing, bullying, threatening, assaulting, and damaging property, that represent diagnostic criteria of conduct disorder. The number of “yes” responses was averaged to create a total score reflecting youths’ average level of conduct-disorder symptoms. Higher scores indicate greater symptoms. Regarding juvenile offending, you could ask youths directly whether they had been arrested, convicted, or incarcerated because of a crime. Youths who responded “yes” to any of these were classifiable as having an arrest record.
And the reference is here:
Odgers, C. L., Moffitt, T. E., Broadbent, J. M., Dickson, N., Hancox, R. J., Harrington, H., Caspi, A. (2008). Female and male antisocial trajectories: From childhood origins to adult outcomes. Development and Psychopathology, 20, 673-716.