02/12/2025
What if you could test a new HIV prevention method without giving anyone a placebo?
Scientists at MRC/UVRI and LSHTM Uganda Research Unit have demonstrated a way. By creating counterfactual control groups from well‑matched data (either from past trial placebo groups or contemporary observational cohorts), using a statistical technique called propensity‑score matching.
Their findings suggest that when done right, this approach can give reliable estimates of how well a prevention method works — without risking participants’ health.
But using old or unmatched data can overestimate the benefit.
Read the full paper for more details: https://doi.org/10.3390/vaccines13080844