Note to self: when building a health survey which is going to be compared to an existing survey*, design your questionnaire to be as similar as possible to the existing one, even if it's not the way you'd do it. This will save you a lot of trouble down the road lining up all the data.

Oh well. Live and learn.

* #NHANES, in case you were wondering, which of course you were. https://wwwn.cdc.gov/nchs/nhanes/