|Symbols taken from Microsoft Powerpoint|
That is, a middle-school kid with middle-school kid financial and physical resources and above average, but not 99.996 percentile, middle-school intellect.
This thought was sparked by a comment made by Aggie HERE:
"Make the AM circle a yellow sun (with circumferential rays) and the PM circle a white crescent moon, my suggestion."
While I really like Aggie's thoughts (Thank-you Aggie!!!) this issue is too important to leave to opinion. The issue is, "How might one modify the doors on the common pill caddie to maximize the user's ability to discriminate 'which door'?"
One way to do that would be to add a tactile element to the visual element.
Can a person with diminished eyesight improve their ability to discriminate based on running their finger tip or finger nail across the door?
Back to middle-school level science
The proposed experiment would involve allowing subjects to look at two plaques with different patterns on them.
Then put the plaques into a box with arm-holes ask the subject can discriminate between the two plaques solely by sense of touch.
The patterns could be both visual and tactile if the pattern were cut out of paper (0.04"), paper plate material (0.12"), and cereal box material (0.20") or three levels, and glued to the plaques (3"-by-5" index cards).
Furthermore, the sense of touch could be diminished by asking the subjects to attempt discrimination with bare skin and then with rubber gloves. That would attempt to simulate the diminished sensitivity due to advanced diabetes.
I don't mean to belabor the point, but these are materials that are well within the budget or scrounging ability of the typical middle school kid. And it is real science with real benefits to society.