Before and after test for binomial variables with few observations

[Amaya de Cos]

Hello!

I have been struggling with what I thought was an easy problem for a while now.
I am runing a before and after analysis for some binomial and categorical variables for which I am using a McNemar test since my data is paired. After doing some research I have been using the following code for both my binomial and my categorical variables:

symmetry FruitT0 FruitT1, contrib exact trend

However some of my 2x2 tables show that there are some empty cells and b + c <25, as far as I know, those variables should not be tested with a McNemar test. I have been doing some research and I can't seem to find the propper answer. In those cases my goal is to see if there are any differences in the number of people who have ever been diagnosed with let's say diabetes in year 1 vs year 2. Since the question says "Have you ever been diagnosed.." we will always have more people diagnosed in year 2 than in year 1 as someone who has been diagnosed cannot be undiagnosed and therefore cell b (or c depending how you look at it) will always be 0.
Some people suggest the best approach is to use a binomial exact test

bitest Diab == 0.5

while others suggest to use a logistic regression

melogit Diab i. Year || ID:

However I don't think it quite means the same thing since.

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So my question here is: what is the right approach in this case and why? and also is there also a better test for categorial variables?

Thank you very much!

[Joseph Coveney]

my goal is to see if there are any differences in the number of people who have ever been diagnosed with let's say diabetes in year 1 vs year 2. Since the question says "Have you ever been diagnosed.." we will always have more people diagnosed in year 2 than in year 1 as someone who has been diagnosed cannot be undiagnosed

It seems like any question about NHST methods is moot. You've just said that your null hypothesis will always be false.

[Amaya de Cos]

First of all, thank you Joseph Coveney for your reply.
I am sorry, I don't think I expressed myself right. I meant to say that there will never be less people diagnosed not that there will always be more people. It can actually stay the same or just have 2 or 3 people diagnosed in year 2.
I want to see if there is a significant increase on the people who have ever been diagnosed in year 2 vs year 1.
I apoplogize for the confusion, I hope it's more clear now. Thank you!