> Four predetermined questions were posed regarding sun exposure: (i) How often do you sunbathe during the summertime? (never, 1−14 times, 15−30 times, >30 times); (ii) Do you sunbathe during the winter, such as on vacation to the mountains? (no, 1−3 days, 4−10 days, >10 days); (iii) Do you use tanning beds? (never, 1−3 times per year, 4−10 times per year, >10 times per year); and (iv) Do you go abroad on vacation to swim and sunbathe? (never, once every 1–2 years, once a year, two or more times per year). The four questions were dichotomized into yes/no in the analysis (i.e. sometimes versus no or never). We created a four-score variable as a measure of sun exposure depending on the number of ‘yes’ responses to the above questions on a scale from 0 (avoid sun exposure: reference) to 4 (greatest sun exposure). Sun exposure habits were categorized into three groups: zero ‘yes’ responses (avoidance of sun exposure; the main study group); ‘yes’ responses to one or two questions (moderate exposure); and ‘yes’ responses to three or four questions (greatest exposure).

Of note, the surveys are of Swedish women and were conducted in Swedish. There could be some translation nuance for the word "sunbathe" which doesn't map well to English, or other cultural differences to explain the "but no one I know actually sunbathes..." thought that I immediately jump to.

[0] https://onlinelibrary.wiley.com/doi/10.1111/joim.12496