Getting ethics into practice

During the editing process of this editorial by Michael J Parker, we tried to be helpful by adding, in the third paragraph, an explanation of what the Tuskegee study entailed (17 July, p 126). Unfortunately, our explanation was not strictly correct. The Tuskegee study was an observational study of patients who had contracted syphilis; it did not involve the deliberate infection of patients (which is what our explanation suggested).