if you don't want to risk getting a placebo you can decide to only do trials that are doing dosing studies, (where everyone gets the drug just in different doses) or doing with different combinations etc. you can read up on the trial design before you make a decision so you know if any of the groups get placebo. (if you do choose to participate in one that has a placebo group you won't know if you're in that group but that's no worse that if you sat at home and did nothing and at least you get closely monitored and contribute to the advancement of knowledge that might help others including your daughters.)