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This Statistics Note by Altman and Schulz rightly stresses the
importance of concealing the treatment allocation, prior to randomising a
patient into a study. However, it seems to neglect one sure way to do
this: not having a prespecified allocation sequence. If the trialist waits
until the person has been entered into the study before determining her or
his allocation, this will be more
secure than trying to hide a pre-existing allocation sequence. For
example, in some central telephone randomisations, the patient details are
collected not simply to confirm eligibility but also so that a computer
programme can generate the patient's allocation, based on the information
collected. In this way, the patient's allocation cannot be obtained until
her or his details have been entered. Is it possible to use random number
generators in off-the-shelf computer packages to do something similar?
Last moment randomisation and concealment
This Statistics Note by Altman and Schulz rightly stresses the
importance of concealing the treatment allocation, prior to randomising a
patient into a study. However, it seems to neglect one sure way to do
this: not having a prespecified allocation sequence. If the trialist waits
until the person has been entered into the study before determining her or
his allocation, this will be more
secure than trying to hide a pre-existing allocation sequence. For
example, in some central telephone randomisations, the patient details are
collected not simply to confirm eligibility but also so that a computer
programme can generate the patient's allocation, based on the information
collected. In this way, the patient's allocation cannot be obtained until
her or his details have been entered. Is it possible to use random number
generators in off-the-shelf computer packages to do something similar?
Competing interests: No competing interests