Clinicians guide to statistics and epidemiology in mental health

167 Pages·1.47 MB·english

by  Ghaemi S.

A Clinician’s Guide to
Statistics and
Epidemiology in
Mental Health

A Clinician’s Guide to
Statistics and
Epidemiology in
Mental Health
Measuring Truth and
Uncertainty
S.NassirGhaemiMDMPH
ProfessorofPsychiatry,TuftsUniversitySchoolofMedicine
Director,MoodDisordersProgram,TuftsMedicalCenter
Boston,Massachusetts
CAMBRIDGEUNIVERSITYPRESS
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© S. N. Ghaemi 2009
This publication is in copyright. Subject to statutory exception and to the
provision of relevant collective licensing agreements, no reproduction of any part
may take place without the written permission of Cambridge University Press.
First published in print format 2009
ISBN-13 978-0-511-58093-2 eBook (NetLibrary)
ISBN-13 978-0-521-70958-3 Paperback
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are strongly advised to pay careful attention to information provided by the
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Tomyfather,KamalGhaemiMD
andmymother,GuityKamaliGhaemi

Errorsinjudgmentmustoccurinthepracticeofanartwhichconsistslargelyof
balancingprobabilities.
WilliamOsler(Osler,1932;p.38)
Thegeniusofstatistics,asLaplacedefinedit,wasthatitdidnotignoreerrors;it
quantifiedthem.
(Menand,2001;p.182)

Contents
Preface xi
Acknowledgements xiii
Section1: Basicconcepts 12 Evidence-basedmedicine:
defenseandcriticism 87
1 Whydataneverspeakfor
themselves 1 13 Thealchemyofmeta-analysis 95
14 Bayesianstatistics:whyyour
2 Whyyoucannotbelieveyour
eyes:theThreeC’s 5 opinioncounts 101
3 Levelsofevidence 9 Section6: Thepoliticsof
statistics
Section2: Bias
15 Howjournalarticlesget
4 Typesofbias 13
published 113
5 Randomization 21
16 Howscientificresearch
6 Regression 27 impactspractice 117
Section3: Chance 17 Dollars,data,anddrugs 121
18 Bioethicsandthe
7 Hypothesis-testing:the
clinician/researcherdivide 127
dreadedp-valueand
statisticalsignificance 35
8 Theuseofhypothesis-testing
Appendix 131
statisticsinclinicaltrials 45 References 138
9 Thebetteralternative:effect Index 144
estimation 61
Section4: Causation
10 Whatdoescausationmean? 71
11 Aphilosophyofstatistics 81
Section5: Thelimitsof
statistics