If you've seen those ads for clinical research studies looking for people with specific conditions (or in many cases, no chronic conditions at all, to serve as a control group), you may have wondered if it would be a good idea to participate in one of those studies because they tend to pay. Sometimes the studies are small -- maybe they draw your blood and that's it -- but you'll also see studies that need several people to help investigate medications. Consider the pros and cons carefully to ensure that you make the right decision.

Financial Compensation

Human subjects in studies should be paid, and this is a big reason why many join in the first place. Generally, the longer the study, the more you have to do, or the more experimental it is (for example, taking a new medication that's being studied vs. tracking what you eat daily and not ingesting anything unfamiliar), the more you'll be paid. If you think the money you'd get would be adequate compensation, especially if you have to miss work, then it might be worth joining. But if you get the feeling the pay is rather low and wouldn't be worth the time, listen to your instincts.

Unknown Effects

If the study is looking at a medication or procedure, you have to take into account what the effects might be. For example, let's say there's a clinical research study for a new diabetes drug that has gone through control-only studies on non-diabetics (these studies give researchers a baseline for how the drug affects a person's system), but that is now going through testing to see how people with diabetes react. If studies on control groups have not shown any adverse side effects, you could consider signing up. But if there is a list of side effects you're not willing to risk, it might not be the study you want to join.

Clearance From Doctor

Even if there appear to be no bad side effects, though, you'd still want to get clearance from your doctor. The study could interfere with other conditions you have, or you may already be having excellent results with a current treatment you're undergoing. Your doctor might not want you to break away from an already-successful treatment.

If the study is a non-invasive one, though -- tracking your diet and exercise, undergoing psychological tests, and so on -- your doctor could give the OK. It helps to have a doctor who is familiar with your current state of health also monitoring you as you go through another study.

Advancing Knowledge

Finally, there's the fact that if you participate in the study, you'll help advance knowledge of a particular condition. If all other factors line up and seem OK, you may want to join the study so that the researchers can get more information about how a medication, procedure, technique, and so on actually works.

There's no harm in calling the research study line listed in the ad to get more information. Write your questions down before you call, and write down the answers you get. Show them to your doctor, and go from there.