Evaluation of the Performance of GFR Estimating Equations in HIV Positive Patients

General description: The overall study procedure requires assessment of eligibility and safety for inclusion in the study (through a "screening questionnaire" and "health screening visit") and if eligible, a one day study visit ("Study visit").

Screening questionnaire All subjects, whether they are interviewed during a clinic visit or call in response to fliers, will be give the pre-screening questionnaire. This will be given to people who voluntarily express interest in the study. Participants who do not disclose any conditions that would exclude them from participating will be invited to a health screening visit.

Health screening visit The purpose of the pre-study health screening is to perform a more detailed assessment than is provided in the screening questionnaire to determine if potential subjects are eligible to participate in the study. A member of the research team will first read the consent form with the subject, describe the health screening and study visits, and answer any questions that the subject has regarding the nature of the study and/or study procedures. The screening visit will consist of the following:

• Reading and signing the study consent. The subject will be given a copy of the consent.
• Collection of information on demographics and current and past health history.
• Ascertain participants medical history through participant interview and a review of his/her medical record
• A physical exam, which will include measuring and recording vital signs (temperature, blood pressure, heart rate, breathing rate), height, weight (if not documented in medical record in past 3 months).
• Collection of a blood sample for laboratory testing, if required, as described in Table 4.
• Pre-menopausal women of child-bearing potential we will undergo a serum pregnancy test, using a small amount of blood from the sample collected above.
• Ascertainment of current and recent past medications.

If the subject is a patient at Tufts Medical Center, a research team member may access the potential participant's medical record after the subject has signed the consent form to further screen for potential exclusion criteria, ascertain laboratory test results that are necessary for determining eligibility, and confirm the medical history provided by the potential participant and medication list. If the participant is not a patient at Tufts Medical Center, then the research team member will obtain permission to obtain the participant's medical record from his/her physician.