A long story made too short: surrogate variables and the communication of HPV vaccine trial results

摘要

The story of epidemiologists and surrogate variables is one of a classic love-hate relationship. Epidemiologists love surrogates because many studies would not be possible without them. When events are rare or the time between an intervention and the outcome is long, surrogate variables are used to fill the gap. Epidemiologists hate surrogate variables because they introduce an additional step in the chain between intervention (or exposure) and outcome, and thus an additional source of error. To introduce surrogates means to increase uncertainty -and, perhaps, an error.