Spine
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Retrospective study of prospectively collected data. ⋯ 3.
-
Retrospective analysis of prospectively collected data. ⋯ 4.
-
Retrospective cohort study. ⋯ 3.
Retrospective study of prospectively collected data. ⋯ 3.
Retrospective analysis of prospectively collected data. ⋯ 4.
Retrospective cohort study. ⋯ 3.