Selective recruitment designs try to estimate how much statistical information a person is likely to provide on a clinical study. Individuals that are considered to be sufficiently informative are recruited, otherwise they are rejected. A selective recruitment design results in a cohort that is enriched for statistically informative individuals.
The advantage of such an approach is that fewer recruits are required to achieve a successful clinical study. This can have potential economic savings and ethical advantages. Selective recruitment designs provide a flexible adaptive framework for efficiently establishing statistical associations between treatments and clinical outcomes.