Of course they're different for oral versus administered by the doctor. The reason is it's because when they're administered by the doctor, the doctor has a schedule. He's going to provide that. He's going to be there to make sure the patient in fact takes it.
With regard to oral, it's the same two things that affect it here that I mentioned in the previous one. People, who are of that age and have chemo brain, are likely to forget it a few times. Heck, they might forget it for a couple of days. There's got to be a way to prevent that from happening.
The second thing is that, if in fact they only have a certain amount of money to pay for their drugs, they may choose to ration their drugs, even knowing that they'll be far less effective.
You may go through the whole educational process, which I think there should be an educational process, to tell them how important it is, and that you can't skimp, but when it comes right down to it, it's all about the money.