Appendix A.
Control variables used in the creation of the propensity score for gang membership.
| Wave 1 variable | Coding description |
|---|---|
| Age | Age of respondent in years |
| Race | Dummy variables for white, black, hispanic, and other race/ethnicity |
| First-generation | Coded 1 if not born in the U.S. and 0 otherwise |
| Both parents in the home | Coded 1 if both biological parents present in-home and 0 otherwise |
| Number in household | Number of residents in the household |
| Same residence | Coded 1 if reside in the same residence as 5 years ago and 0 otherwise |
| Parental permissiveness | Summed 7-item parental permissiveness scale |
| Maternal attachment | Averaged 2-item maternal attachment scale |
| Maternal involvement | Summed 10-item maternal involvement scale |
| Grade point average | Coded as the average 4-point GPA for English, history, math, and science |
| School bond | Averaged 3-item school/student bond scale |
| School engagement | Averaged 3-item school engagement scale |
| Depression | Averaged 19-item depression scale |
| Thought about suicide | Coded 1 if seriously thought about suicide past 12 months and 0 otherwise |
| Negative future outlook | Averaged 3-item negative future outlook scale |
| Impulsivity | Averaged 4-item impulsivity scale |
| Drug use | Summed 3-item drug use scale |
| Friend drug use | Summed 3-item peer drug use scale |
| Delinquency | Averaged 15-item delinquency involvement scale |
| Victimization | Coded 1 if jumped/assaulted and 0 otherwise |
| Witnessed violence | Coded 1 if saw someone shot/stabbed and 0 otherwise |
| Safe in neighborhood | Coded 1 if usually feel safe in neighborhood and 0 otherwise |
| Neighborhood density | Persons per square mile in responden’s census tract |
| Neighborhood disadvantage | A standardized score of socioeconomic status for responden’s census tract |
| Ever sex | Coded 1 if ever had sexual intercourse and 0 otherwise |
| Recent sex | Coded 1 if sexual intercourse prior 12 months and 0 otherwise |
| Romance sex | Coded 1 if sexual intercourse with a romantic partner and 0 otherwise |
| Romantic partners | Number of romantic sexual partners prior 12 months (range 0 to 3) |
| Nonromance sex | Coded 1 if the sexual relationship with nonromantic partner and 0 otherwise |
| Nonromance partners | Number of nonromantic sexual partners prior 12 months (range 0 to 10) |
| Region | Dummy variables for Northeast, Midwest, South, and West |
| Sampling weight | Add Health sampling weight at Wave II |