Table 4 Desire to repeat amyloid positron emission tomography scan

Themes that endorsed undergoing repeat amyloid PET/example quotes

To assess potential change in the scan result

 • “Because like they told me at the end that there wasn’t any assurance that just because I didn’t have enough amyloid then that it didn’t get out of control between then and now or that I was progressing and didn’t know it.” (82-year-old female)

 • “Well, because, you know, when they say at this time, you know you kind of wonder well, maybe I just didn’t have it yet but could be getting it later, you know. So it would be interesting to uh, find out if in fact I was getting it, but just later than my sister.” (72-year-old female)

To help advance research

 • “Again, I would like to help out with any tests I could do that would help find a cure for Alzheimer’s.” (73-year-old female)

 • “Um, I didn’t have any problems with the procedure, I thought it was an interesting thing to do, and um, again, you know, if it’s a data point that helps with research, why not?” (66-year-old female)

To learn updated risk for AD

 • “Because I’d rather know than not know … whether there is at least some indication of susceptibility to uh, Alzheimer’s or another dementia.” (77-year-old male)

 • “Oh, that’s easy. Very likely. I like to know. Because forewarned is forearmed. In other words, if I found out that I had uh, say it was just a study to find out oh, how many people have it, I’d be interested in knowing because that tells me, gee, uh, you might be at a higher risk, so that tells me, I had better do something about it, or at least I should watch it.” (77-year-old male)

Curiosity

 • “Oh, I’m curious to see whether I’m going to develop them or not. I’m just, just a general curiosity, too, and it’s something to do. I’m retired, so.” (72-year-old male)

 • “Well because maybe, it’s not so much I have to know. It would be nice to know.” (69-year-old female)

Due to a negative experience or safety concerns

 • “Because I’ve already had one, and I didn’t enjoy that PET scan. I have claustrophobia, and that was all I could do to take care of that one.” (78-year-old female)

 • “I would say, why don’t you use this recent PET scan we already had…, because I don’t like radiation, especially on top of even more radiation…. However, I might rethink that if it’s a good study.” (78-year-old male)

Repeat imaging is unnecessary

 • “Well probably unlikely because if I was negative a year ago and I haven’t seen any issues, I don’t think anything would be popping up in a year.” (67-year-old male)

 • “I don’t think I feel the need to have one now. I might reach a point in the future that I would be interested or willing to have another. I think again, if I reached a point where I thought my memory was uh, that I was really concerned about it, I would probably, and I was interested in getting a diagnosis or um, knowing some heightened risk situation, I’d probably follow up with it again.” (68-year-old female)