PRO as it is called - The Patient reported outcome may be defined is a questionnaire used in a clinical trial or a clinical setting, where the responses are collected directly from the patient. Typically in a clinical trial, when the drug is manufactured, the pharmaceutical company needs to test the drug at various stages and levels on patients or other wise called ‘subjects’. As the drug is tested over the different phases of the clinical trial on the patients, there is continuous testing that goes on at the back-end – done by the clinical research team. Every patient who is screened in for a particular trial and given their dozes, needs to comply to the medication guidelines prescribed by the investigator by taking the medication on time and then filling up a questionnaire – This questionnaire is called the PRO – The patient reported outcome that the patient needs to fill as mentioned by the investigator. – Well, I am not talking too much in detail in this blog, but will certainly elucidate on the different stake holders, terminologies and processes that go in while a clinical trial in is process –

As mentioned above the PRO that is usually a paper questionnaire comes with several questions ranging between a few to many- some times about 70- 100 questions. Well, it would be incorrect to state that these are the right numbers as the number of questions in a PRO may differ – case to case , Study to study.
A PRO (patient reported outcome) is usually used to assess a patient’s in any one of the following constructs:
1. Symptoms (impairments)
2. Functioning (disability)
3. Health related quality of life (HRQOL)
4. Quality of life questionnaires (QOLs)

A few examples of the types of PRO may be given below:
SF-12(Health Survey), SF-36 (Health Survey), Adult Asthma Quality of Life Questionnaire (AQLQ), Migraine Specific QOL (MSQOL).

You can check out about PRO related QOLs online, people have posted many sample questionnaires. EX: http://www.nephrology.rei.edu/SF36.pdf


Most often there is a little confusion when people talk about Patient reported outcomes and Patient based outcomes – There is a slight yet large difference in the two terms that is usually used in the clinical trials industry.

Patient PRO - Implies only that the patient provides the information. This information may, or may not, be of concern to the patient.

Patient Based Outcome – A patient based outcome implies that questionnaire covers issues of specific concern to the patient.