Things Your Friends Have Done

The 16 items of Things Your Friends Have Done tap domains of delinquent behavior and illicit drug use. (Elliott, D.S., Huizinga, D., & Ageton, S.S., 1985).


The Things Your Friends Have Done (TFD) interview was first administered in Year 5. The 16 items tap domains of delinquent behavior and illicit drug use. It was administered as part of the child interview which is administered in the home setting during the summer. For each item, the child is asked to give a yes/no answer.

The measure was scored based on a conceptual scoring system reflecting the behavioral domains of interest to the investigators, and was divided into four scales; delinquency, alcohol use, tobacco use, and other drug use (marijuana, heroin, crack, cocaine, LSD, or sniffing the fumes of harmful substances).

Note that all four scales are skewed (see Technical Report dated July, 1997). The Del scale can be transformed using a square-root transformation to reduce the skew values, but a square-root transformation was not successful for the Oth scale. The single-item scales of Alc and Tob can not be meaningfully transformed, so these three scales (Oth, Alc, and Tob) may be recoded into dichotomous variables (0=absent, 1=present). Thus ordinary least squares regression can be used for the recoded Del scale, whereas logistic regression is required for the Oth, Alc, and Tob scales.

Dataset Names

Raw Dataset Name: CyN
Scored Dataset Name: TFDySCc


Physical Aggression, Theft, Smoking, Tobacco, Substance Abuse, Gangs, Vandalism, Alcohol, Drugs, Illegal Activity.