======  Study Classification ======

[[Retrospective study]]

[[Prospective study]]

[[Multicenter study]]

[[Observational study]]
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[[Analytical observational study]].
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[[Anatomic study]].
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[[Case-control study]].
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[[Clinical case study]]-[[Case report]].
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[[Clinical trial]].
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[[Cohort study]].
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[[Correlational study]]
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[[Cross-sectional study]].
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[[Descriptive study]].
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[[Expert opinion]].
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[[Experimental study]].
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[[Genome-wide association study]].
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[[Historical vignette]]
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[[Intention-to-treat analysis]].
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[[Kaplan Meier analysis]].
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[[Letter to the editor]] or response
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[[Meta-analysis]].
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[[Original research]].
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[[Perspective]], [[opinion]], and [[commentary]].
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[[Population-based study]].
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[[Prognostic study]].
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[[Proof of concept]] study
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[[Qualitative study]].
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[[Review article]].
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[[Book review]].
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[[Systematic literature review]],
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[[Scientific Trial]].
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[[Technical note]].
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[[Univariate analysis]].
===== Primary study =====


In a primary study, the analysis is performed on only one measure, and in a secondary study the analysis is performed on several measures.

see [[Primary study]].

===== Secondary study =====


[[Secondary study]].

[[Proof of concept]] study
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[[Single-center trial]].

[[Multicenter trial]].
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[[Single-arm trial]]

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[[Noninferiority trial]]
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More terms and examples
A [[randomized]] double-[[blinded clinical trial]] with a [[crossover research design]].

===== ICONS study =====
[[ICONS study]]