Value of being in research studies

I met with a gentleman interested in making it easier to engage people with early stage Alzheimer's in research. It is imperative to the successful completion of a study that people are willing to be in the study. He told me something I'd never thought of before; the cost of research goes up double if the study is unable to retain subjects, and many treatments for Alzheimer's never make it to the table due to lack of study subjects. As I mentioned in another blogspot, my husband and I are in the HOPE study at BU in Boston. I will take part in other research as I am fit as a subject.
What keeps persons in early stage Alzheimer's from participating. It is probably a combination of fear, denial, and not finding the time. But it is imperative we find answers to the Alzheimer dilemma.
As one who has seen the results of not being willing to look at the fact that one has a diagnosis of Alzheimer's, I can say that the journey is much harder for all concerned. Medical and non-medical treatments are available but one won't benefit from them if no one pursues these options.