Business people shaking hands and one of them holding fingers crossed behind back, Represents the betrayal.
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Professional Subjects

While most subjects enter clinical trials for the right reasons, a statistically powerful number of subjects have found that they can participate in several studies at once. Their motivations may be to increase the chances of receiving active medication, or to receive attention from health care professionals. However, by far the most common motivation is financial gain. Professional subjects may tell investigators what they need to hear in order to be enrolled, collect multiple stipends and not take study medications, while reporting perfect adherence.

The professional subject problem is particularly acute in studies with subjective endpoints, such as in psychiatry or pain. Before subject registries existed, duplicate subjects were tracked internally within a few pharmaceutical companies. This only detected the tip of the iceberg, as participation across sponsors or indications was not tracked.

Professional subjects may magnify symptoms to meet ratings criteria, only to improve dramatically and skew study results. Professional subjects who do not take study medication or placebo may influence study results. Even those who do take study medication may deny exclusionary conditions and previous study participation, threatening their safety. Websites are available to assist and support subject participation in multiple studies, such as GPGP (guinea pig guinea pig).net, JALR (Just Another Lab Rat).org and Study Scavenger.

Financial incentives for subjects, sponsors, vendors and investigators certainly contribute to the problem.

  • Central recruiters are paid for the number of subjects they deliver to sites.
  • Subjects are “reimbursed” more if they participate in several studies at once.
  • Sponsors focus on recruitment and retention, rather than who is being recruited and retained.
  • Investigators are not reimbursed for time spent recruiting and prescreening, unless the subject signs consent.
  • These incentives, the internet, and a culture that has come to accept dishonesty contribute to the large number of professional subjects.

Therefore, there is a need for a registry to identify inappropriate subjects and mitigate their destructive effects on studies.


Conceptualized in 2010 by Dr. Tom Shiovitz, a 30-year Principal Investigator who witnessed first-hand the havoc that professional subjects could wreak upon studies:

  • CTSdatabase (CTS) tracks duplicate and professional subjects without the possibility of compromising their identity.  
  • Unlike other registries, identifying information like multiple letters of a name or multiple numbers in a driver’s license is never collected.
  • An iterative, algorithm-based technology, CTS provides the optimum level of privacy and security.  Taking only minutes to train and access the system, CTS has been repeatedly upgraded to improve the user experience. CTSdatabase is powered by CenExel, the largest therapeutically-focused site network in the world.

Most important is our service to sponsors as a partner in study success. We help support, rather than burden, the study team. With nearly 100,000 unique subjects in our database, we take pride in providing the most actionable data, being the easiest for sites and sponsors to utilize, while providing the highest quality service.