Spine
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Prospective multicenter study. ⋯ 3.
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Follow-up study. ⋯ 3.
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A retrospective case-control study. ⋯ 3.
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A prospective study. ⋯ 4.
Prospective multicenter study. ⋯ 3.
Follow-up study. ⋯ 3.
A retrospective case-control study. ⋯ 3.
A prospective study. ⋯ 4.