Table 6.

Illustrative quotes for the 3 overarching themes.

Theme/category	Illustrative quote
Pretraining effectiveness	“Would like a YouTube channel/clip to watch in advance that will explain the device.” (Participant #38) “The most difficult step was probably removing the cartridge from the box. I was not sure if I had to keep the cartridge clean for measurements and the instructions did not tell how I should be holding the cartridge or if I should even be careful or not about touching it too much and getting it dirty” (Participant #18) “The device was cumbersome (awkward) to use because it was the first time. After the first time, it would be easier to use.” (Participant #40)
User friendliness of PointCheck	“Others can’t see as well, may need others to help them if they have dementia or are forgetful.” (Participant #53) “Could not read font of the three step instructions.” (Participant #65) “If I were to use the device on a daily basis, I would be relatively annoyed by the fact the three repeat questions are timed lag to press yes.” (Participant #15) “One thing I was confused about was checking off ‘was my finger in all the way.’ It was just a circle and I was confused what I was supposed to do on this step.” (Participant #21) “The cartridge lid is shown to be peeled from the flat side (facing down) but then needs to be rotated to be put in with the flat side up. If the peel could be opened in the right orientation, that would have helped.” (Participant #24) “Very crisp, and clear how to start using it...the screen has good contrast, good font choice given resolution and size, and the purple/grey color scheme is also calming.” (Participant #30) “Even though I knew beforehand that I should rest my elbow, I forgot to do so after inserting my finger because that was my main focus, so I really appreciated the reminder to have my elbow rested right after the step where I inserted my ring finger.” (Participant #34)
Ergonomic Design	“The display seems angled a little high, considering that the machine needs to be placed a considerable distance to rest my arm. The steps were fairly intuitive.” (Participant #3) “I was expecting the device to be a bit smaller. I think the device is designed for a very big hand, I think it would be probably better to try to make it the size closer to a computer mouse.” (Participant #16) “My fingers are pretty small and narrow but the soft spiked insides of the capture cylinder still left marks on my finger afterwards. This was completely non-painful but just noting this here for other users who might have thicker fingers! It was a bit bigger than I expected (the size of the device) but it doesn’t impact usability. It also produced quite a loud hum but again, doesn’t impact usability.” (Participant #11) “I liked the brush-like texture inside the tube. It helped me feel that I had my finger in the right position.” (Participant #33) “My first impression was that it looked pretty compact and that it’s very straight to the point in its features--nothing fancy, just functional.” (Participant #34)