Day 2 SeminarTypes of research articles

Original research article

new knowledge

for the first time

Other types of articles in journals:

Case reportReview article

Editorial material:EditorialsCommentariesViewpointsLetter to editorBook or media review

Observational studies◦Cross-sectional / prevalence◦Case-control / retrospective◦Cohort / prospective

Experimental studies◦Controlled clinical trials

Hierarchy of evidence

1. N of 1 randomized control trial 2. Systematic reviews of randomized control trials 3. Single randomized control trial 4. Systematic review of observational (cross-sectional, cohort,

or case-control) studies 5. Single observational (cross-sectional, cohort, or case-control)

study 6. Physiologic studies (studies of blood pressure, cardiac

output, exercise capacity, bone density, etc) 7. Unsystematic clinical observations (case series, case report)

Cross-sectional study

Case control study

Cohort study

sadašnjostprošlost budućnost

Historical cohort study

Experimental research

Time of study group formation

Time of data collection

Past Present Future

Hierarchy of evidence http://www.cebm.net/index.aspx?o=1025

Centre for Evidence Based Medicine, University of Oxford

Levels of evidence for: • Therapy / Prevention, Aetiology / Harm• Prognosis • Diagnosis • Differential diagnosis / symptom prevalence study • Economic and decision analyses

http://www.ted.com/talks/ben_goldacre_battling_bad_science?language=en