system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
An investigator into the life expectancy of IV drug abusers divides a sample of patients into HIV positive and HIV negative groups. What type of data does this division constitute?
assistant
The correct answer is  In the question, data has been divided into two groups, i.e. HIV positive/HIV negative → Data should be measured on the nominal scale especially Dichotomous type of nominal scale.