The kind of subject vulnerability that lies at the core of the partial entrustment between researcher and subject stems from the fact that it will he affected by subjects' health how researchers exercise the discretion that subjects indirectly grant them.
That is because the more subjects have been willing to expose themselves to possible risks or discomforts, the more researchers owe them a debt of gratitude; and the more that gratitude is owed, the stronger the case is for their entrustment responsibilities.
Desperately ill people who turn to research protocols as their "last, best hope" are quite dependent upon the resulting relationship of entrustment.
As with the scope of entrustment, these strengthening factors will vary with the evolving depth and intensity of the relationship between a researcher and subject.
First, one must decide if a given type of ancillary care falls within the scope of the subjects' evolving, partial entrustment of their health to the researchers.
Care for these injuries is not within the scope of entrustment, however, at least when the common sequelae leave visible traces in limps or deformed limbs.
Certainly diagnostic reading is within the scope of entrustment.
The scope of the entrustment depends on the nature of each study, and specifically on the needed range of permissions that subjects grant researchers.
Partly because she intends her account of entrustment as a basis for understanding trust more generally, she does not distinguish as we do between grants of discretionary authorization and simply placing one's head inside the lion's jaws.
On the difficulty of eliminating this element of discretion from entrustment relationships, see Baier, "Trust and Antitrust," 237n.