An adaptive biased coin design (Hofmeijer et al, 2008) is one where the value of P for each patient allocation depends on the degree of imbalance in the number of patients previously enrolled to each arm.
Alternatively, one could perform simple random sampling as long as the imbalance in the number of patients previously enrolled to each arm overall, or within a centre or some other prognostic factor, is less than some value m, but switching to a biased coin design when the imbalance is m or larger.
Of this year's more than 4,300 visiting students — those not previously enrolled at Berkeley — 3,084 are from overseas and 1,224 are U.S. residents.
The authors suggest that "even though the previously enrolled perceive NHIS to be beneficial and convenient overall, it may be that they saw fewer advantages in NHIS than originally expected" [ 23].
Of those assessed for eligibility, 1049 did not meet eligibility criteria, 120 were previously enrolled, 527 refused to participate, 474 were unavailable in their hospital room at the time of enrolment and 954 were not approached because the maximum enrolled subject number was reached that day.
We included an equal number to the previously enrolled pregnant diabetic women, in order to obtain statistical equality.
If a previously enrolled control calf converted to a BRDC case, its phenotypic classification was changed from control to a case and two new matched control and case calves were enrolled.
Women who were unable to understand study procedures sufficiently to provide consent (eg, due to cognitive difficulties) had previously enrolled in the study, or were unable to read or understand the written questionnaires in English were not enrolled.
The numbers in the figure are derived from our scenario calculations and based on the assumptions that resources first will be devoted to previously enrolled patients and that the current productivity level remain constant.
Subjects previously enrolled in a study to evaluate pain relief within the past six months or currently involved in any other research study involving an investigational product (drug, device, or biologic) or a new application of an approved product, within 30 days of screening were also excluded from participating in the trials.
Subjects previously enrolled in a study to evaluate pain relief within the past 6 months or currently involved in any other research study involving an investigational product (drug, device, or biologic) or a new application of an approved product, within 30 days of screening, were also excluded from participating in the trial.
