Medicalising normality? Using a simulated dataset to assess the performance of different diagnostic criteria of HIV-associated cognitive impairment.


Underwood J, De Francesco D, Leech R, Sabin CA, Winston A; Pharmacokinetic and Clinical Observations in PeoPle Over fiftY (POPPY) study.

Lay summary

Published research suggests that there is a very high rate of brain problems in people with HIV.  However, the reported rate of brain problems depends very heavily on the way in which we interpret the tests that are performed.  We used a simulated dataset, generated so that it is very similar to the data collected in the POPPY study, to show that the usual approaches to defining brain problems will dramatically over-estimate the proportion of people with real problems.  This will have important implications for people with HIV (some of whom may be falsely told that they have brain problems)