Association of maternal caffeine consumption during pregnancy with child growth

I have no idea how we got sampled -- a staffer visited our hospital room with a clipboard and signed up the kid at birth, but otherwise we would never have known it was an option.

For us they've done occasional detailed phone interviews roughly annually, sent someone to collect biometric data at the kid's regular well child visit, and occasionally requested some poop or blood.

They also enrolled us in a related study during early 2020 -- we were mailing in nasal swabs from the whole family every week or so for a while! (The DIY home blood sample kit they sent was NOT a winner and I promised the kid we wouldn't try it again; they were fine with us opting out of that part of their covid study.)

We get an annual newsletter highlighting recent publications from the study, periodic random $20 checks after phone surveys, and -- oddly -- packages with birthday cards, holiday greetings, and small toys or coloring books every few months. I guess this is how you keep people active in longitudinal studies?

We need to stop doing them.