It depends on the program itself. Some programs are more flexible about the changes that can be made. Once you’ve zeroed in on a possible program, refer to the Core Components and Adaptation Guidelines documents to learn more about whether the program can be adapted for your population. These can be found under Programs, on the "Adaptation Guidelines & Tools" tab on the page that describes the EBP.
Be sure to check FOA guidelines as to whether prior approval is required for any adaptations you are considering.
In addition, please note that ETR owns the original and derivative rights to its evidence-based programs. Developers making significant adaptations to these programs or materials are encouraged to register their efforts with ETR, and must understand that adaptation of an ETR program does not grant the developer of the adaptation the right to disseminate or commercialize the work in any way or represent such work as approved by ETR.