Epidemiology: Key to Prevention

272 Pages·2012·1.42 MB·English

by  Klaus Krickeberg

Statistics for Biology and Health
Series Editors
Mitchell Gail
Jonathan M. Samet
Anastasios Tsiatis
Wing Wong
Forfurther volumes:
http://www.springer.com/series/2848

Klaus Krickeberg Pham Thi My Hanh
l
Pham Van Trong
Epidemiology
Key to Prevention
KlausKrickeberg PhamThiMyHanh
GrosserKamp4 FacultyofPublicHealth
33619Bielefeld,Germany ThaiBinhMedicalUniversity
[email protected] LybonStreet81
ThaiBinh,Vietnam
[email protected]
PhamVanTrong
FacultyofPublicHealth
ThaiBinhMedicalUniversity
LybonStreet81
ThaiBinh,Vietnam
[email protected]
ISSN1431-8776
ISBN978-1-4614-1204-5 e-ISBN978-1-4614-1205-2
DOI10.1007/978-1-4614-1205-2
SpringerNewYorkDordrechtHeidelbergLondon
LibraryofCongressControlNumber:2011938856
#SpringerScience+BusinessMedia,LLC2012
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Preface
This book is the successor to the textbook “Lessons on Epidemiology” (in
Vietnamese) that has been in use at the Medical University of Tha´ı B`ınh since
1990. After a critical analysis of these “lessons” we wrote a completely new text.
It is meant for adoption in the first courses on epidemiology in Medical Schools
andFacultiesofPublicHealthindevelopingandtransitioncountriesandinwork-
shopsinthesecountries,taught,forexample,bymembersofinternationalorgani-
zations. It is also suitable for parallel or second reading within curricula in
developed countries and for teaching epidemiology in a Master’s programme on
“International Health”. The book will enable any lecturer to compose his or her
introductory courses on epidemiology by selecting the material deemed appropri-
ate.Itwillprovideasolidfoundationformoreadvancedteaching.
Hence, the intended readership consists, in the first place, of general medical
students; students following the programme “Preventive Physician”that runs par-
alleltogeneralmedicalstudiesinsomecountries;studentsstartingtospecializein
Public Health; and lecturers in epidemiology. The book can also serve well as an
introductiontoepidemiologyforanybodyelseinterestedinthisfield;forexample,
staffofhealthinstitutionsandstudentsandlecturersofinternationaldevelopment.
Examples and practical work are taken from the present situation of health in
Vietnam. Such a coherent setting in one specific country is seen as an advantage,
not a drawback; it is preferable to illustrations from many countries that will
necessarily remain diffuse and superficial. The book is in fact a large case study
thatcaneasilybeadaptedtoanyotherdevelopingortransitioncountry.
Thegenerallevelisthatwhichcanbeexpectedofstudentswhowereadmittedto
medical studies. The only specific prerequisite is some basic secondary-school
mathematics. Above all, the reader should be ready to think; rote learning is not
encouraged.
When writing the new book we were guided by a few general principles that
concern its purposes, its content, and its didactic approach. Let us sketch them
briefly.
v
vi Preface
Themainpurposeistogivethereaderaclearpictureofthefundamentalideas
thatunderliethefieldofepidemiologyandtorecognizetheirroleinanysituationin
practice.Itisonlybybeingfamiliarwiththeseideasthattherightquestionscanbe
asked in real situations and the right methods can be chosen to solve practical
problems. We emphasize throughout the position of epidemiology as the centre-
pieceofPublicHealth;inparticular,Prevention.
Also,whenreadingthereportonastudy,studentsofMedicineorPublicHealth
shouldbeabletoputitintothecorrectframework,toextracttheessentialsandto
judge its significance and correctness. This is all the more important as most
studentswillneverhaveanoccasionofparticipatingthemselvesinamajorstudy.
They will later on have to base their decisions about practical matters of Public
Health,especiallyaboutPrevention,onpublications.
Our book is not intended to teach details of techniques. When engaged in an
epidemiologic study or faced with an epidemiologic problem underlying preven-
tion, health education, outbreak investigation or control of infectious diseases,
physicians must know which steps are to be taken and why, but they need not
know how these steps look in detail; for that they can consult specialists or
appropriatemanuals.
Thistextwillalsoprepareitsreaderstousestatisticalsoftwarewithdiscernment.
Sincemanydifferentsoftwarepackagesarebeingemployedinvariousinstitutions
wehaveneitherrecommendednorusedaparticularone.
Onemorepurposeofthebookistolaythegroundforwhatwewouldliketocall
“population-sideteaching”,whichisthepublichealthanalogueto“bedsideteach-
ing”ofclinicalmedicine;itisrelatedto,butnotidenticalwith,“community-based
teaching”. Medical students should help health workers on the primary level to
understand simple epidemiologic facts and to describe them and use them if
possible. Part of their training can also take place in direct contact with the
population. Our text provides much material that lends itself to this kind of
teaching.
Regardingthecontentofthisbook,thescopeisfairlylargeandcoverstopicsthat
play an important role in present day health activities but are rarely treated in
existing texts. The topics include registers, health information systems, sample
surveys, and elementary statistics. Much attention was of course paid to non-
infectious diseases. We have also added some topics that are, in our experience,
oftenhandledwronglyintheliteratureandneedtobeelucidated.Neverthelesswe
have tried to restrict ourselves to the essentials. Lesson 28 (Outlook) gives an
overviewofmoreadvancedsubjectsandareasthatcouldnotbetreatedhere.
Atfirstsighttheorganizationofthebookasreflectedinthetableofcontentsmay
notlookverysystematic.Itistheresultofdidacticviewpoints.Wedidnotwantto
startwithgeneraltheoryandhandleapplicationsafterwards.Insteadwehavetried
toplacethetheoreticalbasesattheirnaturalplaces.Thus,inthebeginning,thatisin
Lessons 1–10, most fundamental ideas appear only in a specific concrete context.
They are explained in an intuitive way, not very rigorously, but sufficiently well
sothatthestudentcanunderstandtheirrole.Theoryandmethodsarethenprovided
in Lessons 11–17 when the student has already gained some feeling about them.
Preface vii
Then,armedwiththesetools,wegobacktospecificproblemsbutagain,threemore
theoreticalandgenerallessons(20,21,and24)areputinonlylater,whentheyare
needed.
Thisorganizationalsocorrespondstobasicdifferencesbetweentheepidemiolo-
gy of infectious and of non-infectious diseases. Firstly, in the past, epidemiologic
thinkingindevelopingcountrieswasdominatedbyproblemsofinfectiousdiseases
butatpresentnon-infectiousonesplayanequallyimportantrole.Secondly,modern
general and rigorous epidemiologic methods have been established mainly as a
response to challenges by non-infectious diseases; whereas, problems of the epide-
miologyofinfectiousdiseasescanbehandledtoalargeextentbymoreelementary
tools,withtheexceptionofmathematicalmodelling.Thirdly,andmostimportantly,
most curative interventions against aninfectiousdisease in a community alsohave
anindirectpreventiveeffectbyeliminatingsourcesofinfections;nothingofthekind
existsfornon-infectiousdiseases.
Thereadershouldbeawareofthefactthatthelessonsonspecificproblemsare
determined in two basically different ways: either by the outcome variable as in
Lessons6–10and22–23orbytheexposureasinLessons25and26.
For didactic reasons, too, we have treated systematically only the action of a
single exposure variable, with the exception of Lesson 21 on confounding, where
we have explained everything with the help of two examples. Having understood
theprincipleoftheactionofoneriskfactor,thereadershouldhavenodifficultyin
understanding the essential ideas of the role of several exposures together as they
comeupintheexamplesofLessons22,23,25,and26inaninformalway.
Similarly,wehaverestrictedourselvesmainlytostudyingbinaryexposureand
outcomevariables.
A last important didactic viewpoint is the unity of the book. It should not, and
cannot, be seen as a collection of more or less independent lessons. In particular,
there are very many cross-references, considered as a didactic tool, too. We have
notbeenafraidofbeingrepetitiveinsomeplaces.
Bielefeld,Germany KlausKrickeberg
ThaiBinh,Vietnam PhamThiMyHanh
ThaiBinh,Vietnam PhamVanTrong

Acknowledgements
Several people read part of a first draft and made many useful comments; in
particular, Dinh Ngoc Sy, Leˆ Xuan Hung, Pham Ngoc Dinh, Phan Vu Diem
Hang, Vu Dinh Hai, Bernhelm Booss, Lena Striedelmeyer, Axel Ekkernkamp,
UliSchmucker,andHeikoJahn.NguyeˆnThiThuYeˆnsuppliedtechnicalinforma-
tiononspecificpoints.Tworeviewersaddedpertinentremarks.Toallofthemthe
authorsowemuchgratitude.
Finally, we would like to thank the Else Kro¨ner-Fresenius-Stiftung for their
financialsupportthatmadepossibletheprojectofreformingtheteachingofPublic
Health in Medical Universities in Vietnam and in the National Institute of Public
Health in Laos. Special thanks go to Dr. Carolin Kro¨ner for taking a constant
interestandoftenprovidingencouragement.
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