Spine
-
Retrospective study. ⋯ 3.
-
Cross-sectional. ⋯ 2.
-
A cross-sectional survey by anonymous self-assessment questionnaire was given to 3600 high school students from 30 high schools. ⋯ 3.
Retrospective study. ⋯ 3.
Cross-sectional. ⋯ 2.
A cross-sectional survey by anonymous self-assessment questionnaire was given to 3600 high school students from 30 high schools. ⋯ 3.