Novel Location-Based Survey Using Cognitive Interviews to Assess Geographic Networks and Hotspots of Sex and Drug Use: Implementation and Validation Study

Sean C Reid   ¹ , MA ;   Vania Wang   ¹ , MA ;   Ryan D Assaf   ² , PhD ;   Sofia Kaloper   ¹ ;   Alan T Murray   ¹ , PhD ;   Steven Shoptaw   ³ , PhD ;   Pamina Gorbach   ⁴ , DrPH ;   Susan Cassels   ¹ , PhD

¹ Department of Geography, University of California, Santa Barbara, Santa Barbara, CA, United States

² Benioff Homelessness and Housing Initiative, Center for Vulnerable Populations, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States

³ Family Medicine and Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, United States

⁴ Department of Epidemiology, University of California, Los Angeles, Los Angeles, CA, United States