After last week’s tip on site selection (location, location, location!), this week is still concerned with the design of clinical trials – or why numbers can sometimes lie.

How many times have you heard of an investigator that committed to a certain number of subjects but has not been successful in meeting the recruitment goal in the expected timelines? Investigators are approached very early in the process of site selection, which is natural and expected. They are also asked about their recruitment potential very early in the process, sometimes even before the study protocol is even fully designed. Asking about a potential investigator’s pool of potential patients is important, sometimes critical, for the success of the study and the company. And we all do it, asking about potential recruitment, during the pre-study visit or first meeting with the investigator. Often enough, the investigator’s reply relies not on the study specifications but on his/her general impression and previous experience with similar studies. Then, several months down the line, recruitment rate does not meet your expectations and valuable time and resources are going down the drain.

So here is my tip: You can maximize the value of the reply provided to you by following one of these two options.

1. Schedule the pre-study meetings after you have a clear idea of your study population and specific study requirements. Even if your protocol is not finalized, you can still take into consideration the distinct study characteristics that call for special attention in recruitment.
2. Alternatively, meet your potential investigators at an early stage, but make sure to fine tune their recruitment assessment after you finalize the protocol and before committing to working with any specific investigator. While meeting with them, take the time (although it is generally quite limited for physicians) to go as deep as possible into your requirements.

This tip may sound trivial, but in fact most studies fail to meet their timelines and recruitment goals for this exact reason.

Oh, and just as a general rule: The actual recruitment potential is generally about X4 smaller than the investigator’s initial assessment!