MRCPsych Teaching 2008
Critical Appraisal of Diagnostic Test Studies
Alex J Mitchell
Consultant in Liaison Psychiatry
University of Leicester

Contents
• Importance of understanding diagnostic tests
• Statistics of diagnostic validity
• Examples

Importance of understanding diagnostic tests

What Is a Diagnostic Test in Psychiatry?
• CT/MRI
• CSF
• Blood tests eg TFTs
• SCAN/SCID/PSE/MINI
• Neuropsychological Testing
• MMSE
• HADS/BDI/CESD?
• Clinical Judgement
• Self-report

Why Is a HADS score not a diagnosis?

Why Is a HADS score not a diagnosis?
1. No core features
2. No symptom ranking
3. No functional assessment
4. Duration unclear
5. What if Missing items?
6. Imprecise