Overly restrictive parameters for patient selection are frequently imposed. In such cases, the patient population is defined in terms that make finding patients overly difficult. In some instances, the very nature of the trial itself dictates such restrictive criteria. However, in many cases, criteria are restrictive to the point that recruitment in meaningful numbers is practically impossible. In such a situation, it may seem that companies have little choice but to increase their recruitment budgets, in order to significantly increase promotion levels, forms of promotion, or the number of participating sites.
Many physicians find participation in clinical trials to be a lucrative endeavor.
Top enrollers can become highly visible opinion leaders, in addition to receiving what seems to be an ever increasing per patient enrollment compensation. All of those who seek to become PIs have made some form of preliminary study to estimate the numbers of available patients having the condition of interest. However, these estimates frequently fall short because eligible patients do not enroll in the expected numbers, physician colleagues do not cooperate to the degree expected, patients once enrolled drop out in inordinately high numbers, or other unanticipated problems arise. In such cases, after a study has been budgeted and assigned, new demands for increased incentives become manifest. N umber and types of study sites .