Clinical Trial Care and Compensation

My wife has participated in two clinical trials. One trial reimburse her for car travel expenses, the other did not offer travel expense reimbursement. Neither trial paid her for participating. Neither trial charged us anything. If you live far from the trial site, travel expenses will be a consideration, particularly if you or your spouse must stay in the area during the trial.

Hi... did anybody had to take opioid ( methadone, fentanyl, tramadol) or anth.else for chronic pain and still was eligible to participate in clinical. I hate that they imidiatey exclude you if you take this medication why would they do that if a person needs this medicine very bad and it was prescribed by the doctor? Is there anything that I can provide to the trial group for still being qualifying for the trial...? And I talk about smoking trial... obviously they are not looking 100% healthy people??? Hope you guys can help me with my question.