Final answer:
The Behavior Analyst should leave a business card with contact information at the individual's residence and avoid leaving any additional personal information to maintain confidentiality and comply with HIPAA.
Step-by-step explanation:
When a Behavior Analyst goes to an individual's residence to conduct a behavior assessment and finds no one home, it is important to respect the individual's privacy in line with the Health Insurance Portability and Accountability Act (HIPAA). He should leave a business card only, with contact information so that the individual can reach out to him. Leaving any additional information such as the name of the individual or the specifics of the services to be provided is not suggested, as it could result in a breach of confidentiality and potentially violate HIPAA regulations.