Physician Characteristics, Efficiency, and Clinical Trial Participation

Pharmaceutical drug costs continue to rise. These costs include research and development, clinical trials, regulatory approval, and marketing. In this paper, we examine the single most expensive part of drug development, i.e., clinical trials.

Since very little literature exists, particularly, on the characteristics of the physicians participating in clinical trials, we begin our analyses by describing the demographic, practice, specialty, and research experience of active US clinical investigators, followed by an analysis of investigators' reasons for participating in clinical trials. Investigator profiles are compared to those of the general US physician population. Then, we delve more deeply into the distribution of costs as a function of time, enrollment, and outcomes (successful completion of the clinical trial). For this aspect of our study we use a Cox's regression model to describe the probability of enrolling patients as a function of time and the profile of the clinical investigator and their facility. Using log-linear models, we will also describe the number of clinical trial and the number of patients enrolled as a function of the characteristics of the investigator and of their facility.

The data come from a random sample of 4,234 US physicians active as clinical investigators, drawn from the FDA 1572 file of active investigators. Seven-hundred and sixty two (762) investigators returned the completed mail questionnaire. Prescribing and additional practice profile data were supplied for the sample by the American Medical Association and IMS Health.

The pharmaceutical industry pays nearly $8 billion to investigators to compensate them for their participation in clinical trials. A number of reasons underpin an investigator's decision to participate in a clinical trial. While financial remuneration is an important consideration for many investigators, the prospect of participating in the development of innovative medical treatments is the most important motivation for taking part in a clinical trial.

There is wide variation in how effectively investigators perform in clinical trials. We examine the characteristics of better performing investigators.

Fewer than 2% of physicians serve as principal investigators. The profiles of successful investigators can serve as potential recruiting criteria for additional investigators from physicians who do not now take part in clinical trials. Any attempt though to increase the pool of active investigators must address the reasons for participating in clinical trials, including medical innovation, access to new therapies, and compensation, and how these reasons vary by important types of investigators.