Summary Notes course 'Introduction Descriptive Epidemiology and Public Health' (HNH-28303)

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Notes‌‌course‌‌‘Introduction‌‌Descriptive‌‌
Epidemiology‌‌and‌‌Public‌‌Health’‌‌
(HNH-28303)‌ ‌
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Content‌ ‌

Notes‌‌week‌‌1‌ 2‌ ‌
1.1‌‌Introduction‌‌to‌‌epidemiology‌‌and‌‌public‌‌health‌ 2‌ ‌
1.2‌‌History‌‌of‌‌epidemiology‌‌and‌‌public‌‌health‌ 4‌ ‌
1.3‌‌Descriptive‌‌and‌‌analytical‌‌epidemiology‌ 6‌ ‌
1.4‌‌Measures‌‌of‌‌disease‌‌occurrence/‌‌frequency‌ 6‌ ‌
1.5‌‌Diabetes‌‌prevalence‌ 12‌ ‌
1.6‌‌Self-test‌ 14‌ ‌
Summary‌‌of‌‌the‌‌moderator‌ 16‌ ‌
Learning‌‌goals‌‌week‌‌1:‌ 17‌ ‌
Notes‌‌week‌‌2‌ 20‌ ‌
2.1‌‌Standardization‌ 20‌ ‌
2.2‌‌Mortality‌‌and‌‌morbidity‌ 28‌ ‌
2.3‌‌Assignment‌‌‘cancer’‌ 30‌ ‌
2.4‌‌Epidemiology,‌‌public‌‌health‌‌and‌‌prevention‌ 32‌ ‌
2.5‌‌Study‌‌designs‌‌in‌‌descriptive‌‌epidemiology‌ 33‌ ‌
2.6‌‌Health‌‌in‌‌elderly‌‌people‌ 35‌ ‌
2.7‌‌Self-test‌ 38‌ ‌
Summary‌‌of‌‌the‌‌moderator‌ 40‌ ‌
Learning‌‌goals‌‌week‌‌2:‌ 41‌ ‌
Notes‌‌week‌‌3‌ 42‌ ‌
3.1‌‌Life‌‌expectancy‌‌(LE)‌‌and‌‌CVD‌ 42‌ ‌
3.2‌‌DFLE,‌‌DALE‌‌and‌‌HALE‌ 48‌ ‌
3.3‌‌Disability-adjusted‌‌life‌‌years‌‌(DALYs)‌‌and‌‌Quality-adjusted‌‌life‌‌years‌‌(QALY)‌ 50‌ ‌
3.4‌‌Global‌‌burden‌‌of‌‌disease‌‌and‌‌infectious‌‌diseases‌ 54‌ ‌
3.5‌‌Self-test‌ 60‌ ‌
Summary‌‌of‌‌the‌‌moderator‌ 61‌ ‌
Learning‌‌goals‌‌week‌‌3:‌ 61‌ ‌
Appendix‌‌I‌‌-‌‌Assignment‌‌1.4g‌ 62‌ ‌

Appendix‌‌II‌‌-‌‌Assignment‌‌3.3d‌ 64‌ ‌
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Introduction‌‌Descriptive‌‌Epidemiology‌‌and‌‌Public‌‌Health‌‌(HNH-28303)‌ ‌

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Note:‌‌All‌‌reading‌‌chapters‌‌in‌‌this‌‌summary‌‌are‌‌derived‌‌from:‌ ‌
Webb‌‌C.‌‌&‌‌Bain‌‌P.‌‌(2017).‌‌Essential‌‌epidemiology:‌‌an‌‌introduction‌‌for‌‌students‌‌and‌‌health‌‌
professionals.‌‌Cambridge‌‌University‌‌Press,‌‌3rd‌‌or‌‌4th‌‌edition;‌‌and‌‌Haveman-Nies,‌‌A.,‌‌
Jansen,‌‌S.,‌‌van‌‌Oers,‌‌H.,‌‌&‌‌van‌‌'t‌‌Veer,‌‌P.‌‌(Eds.)‌‌(2017).‌‌Epidemiology‌‌in‌‌public‌‌health‌‌
practice.‌‌Wageningen‌‌Academic‌‌Publishers.‌‌Other‌‌information‌‌is‌‌derived‌‌from‌‌the‌‌
Wageningen‌‌University‌‌and‌‌Research‌‌(WUR).‌‌ ‌
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Introduction‌‌Descriptive‌‌Epidemiology‌‌and‌‌Public‌‌Health‌‌(HNH-28303)‌ ‌

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Notes‌‌week‌‌1‌ ‌
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1.1‌‌Introduction‌‌to‌‌epidemiology‌‌and‌‌public‌‌health‌ ‌
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1.1a‌‌What‌‌is‌‌epidemiology‌‌about‌ ‌
Epidemiology‌‌is‌‌a‌s ‌ tudy‌‌of‌‌up/upon‌‌people‌.‌‌This‌‌focuses‌‌on‌‌the‌‌question:‌‌what‌‌are‌‌the‌‌
distribution‌‌and‌‌determinants‌‌of‌‌health‌‌related‌‌states‌‌and‌‌events‌‌of‌‌populations‌‌(regarding‌‌
health‌‌problems)?‌‌A‌‌more‌‌recent‌‌definition‌‌is:‌‌epidemiology‌‌is‌‌about‌‌measuring‌‌health,‌‌
identifying‌‌the‌‌causes‌‌of‌‌ill-health,‌‌and‌‌intervening‌‌to‌‌improve‌‌health.‌‌This‌‌is‌‌done‌‌by‌‌
systematically‌‌discovering‌‌patterns‌‌in‌‌a‌‌large‌‌amount‌‌of‌‌information.‌‌After‌‌that,‌‌you‌‌analyse‌‌
the‌‌data‌‌to‌‌understand‌‌the‌‌patterns‌‌in‌‌order‌‌to‌‌prevent/intervene‌‌disease.‌‌An‌e ‌ pidemic‌‌‌is‌‌
about‌‌the‌n ‌ ew‌‌cases‌‌‌of‌‌a‌‌disease‌‌in‌‌a‌‌given‌‌population‌‌during‌‌a‌‌given‌‌time‌‌period‌‌occur‌‌at‌‌a‌‌
rate‌‌that‌‌substantially‌e ‌ xceeds‌‌what‌‌is‌‌‘’expected’’‌‌‌(based‌‌on‌‌recent‌‌experience).‌‌A‌‌
pandemic‌‌‌is‌‌an‌‌epidemic‌‌that‌‌spreads‌‌across‌‌a‌‌large‌‌region,‌‌for‌‌example‌‌a‌‌continent‌‌or‌‌
even‌‌worldwide.‌‌An‌e ‌ ndemic‌‌‌(infectious)‌‌disease‌‌is‌‌common‌‌at‌‌a‌‌specific‌‌place‌‌(like‌‌
malaria).‌‌ ‌
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1.1b‌‌Epidemiology:‌‌an‌‌academic‌‌and‌‌applied‌‌science‌ ‌
Different‌‌ways‌‌of‌‌using‌‌epidemiology.‌‌The‌c ‌ linician‌‌‌translates‌‌the‌‌scientific‌‌knowledge‌‌and‌‌
procedures‌‌to:‌‌‘what‌‌is‌‌the‌b ‌ est‌‌treatment‌‌‌for‌‌this‌s‌ pecific‌‌patient‌?’.‌‌The‌e
‌ pidemiologist‌‌in‌‌
academic‌‌setting‌‌‌thinks‌‌about‌‌the‌‌question:‌‌‘how‌‌can‌‌I‌‌be‌‌sure‌‌about‌‌this‌‌specific‌‌
exposure-effect,‌i‌ndependent‌‌‌of‌‌the‌‌context‌‌of‌‌this‌‌person‌‌or‌‌population?’.‌‌And‌‌the‌‌
epidemiologist‌‌in‌‌public‌‌health‌‌setting‌‌‌thinks‌‌about:‌‌‘the‌‌best‌‌prevention‌‌strategy‌‌for‌‌this‌‌
specific‌p ‌ opulation/‌‌risk‌‌group‌’.‌‌The‌‌difference‌‌between‌‌the‌‌last‌‌two‌‌is‌‌that‌‌the‌‌academic‌‌
setting‌‌tries‌‌to‌e
‌ liminate‌‌‌other‌‌factors,‌‌context‌‌and‌‌values,‌‌whilst‌‌the‌‌public‌‌health‌‌setting‌‌
tries‌‌to‌i‌ncorporate‌‌‌all‌‌these‌‌factors.‌ ‌
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Scientific‌‌detective‌ ‌ Crime‌‌prevention‌ ‌

Epidemiologist‌‌in‌a
‌ cademic‌‌setting‌ ‌ Epidemiologist‌‌in‌p
‌ ublic‌‌health‌‌setting‌ ‌

Epidemiology‌‌is‌‌about‌a
‌ nalysing‌‌‌patterns‌‌ Epidemiology‌‌is‌‌about‌‌using‌‌this‌‌
and‌‌causes‌ ‌ information‌‌for‌p
‌ revention‌‌‌in‌‌populations‌ ‌

A‌‌‘detective’‌‌aims‌‌to‌‌analyze‌‌and‌‌ Prevention‌‌through‌‌policies,‌‌programs,‌‌and‌‌
understand‌‌‌these‌‌patterns‌‌(who?‌‌where?‌‌ interventions‌ ‌
when?‌‌why?‌‌what?)‌ ‌

Focus‌‌on‌‌knowledge‌g
‌ eneration‌ ‌ Focus‌‌on‌‌knowledge‌a
‌ pplication‌ ‌

Important:‌ ‌ Important:‌ ‌
● Validity,‌‌precision,‌‌causation‌ ‌ ● Generalizability,‌‌importance‌ ‌
● Relevant‌‌to‌‌mankind,‌‌anytime,‌‌ ● Best‌‌practice‌ ‌
anyplace‌ ‌ ● Relevant‌‌to‌‌me,‌‌here‌‌and‌‌now‌ ‌
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Introduction‌‌Descriptive‌‌Epidemiology‌‌and‌‌Public‌‌Health‌‌(HNH-28303)‌ ‌

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The‌‌chain‌‌of‌‌‘food‌‌→‌‌health’‌‌is‌‌described‌‌below,‌‌together‌‌with‌‌the‌‌place‌‌where‌‌public‌‌health‌‌
and‌‌academic‌‌epidemiology‌‌is‌‌positioned.‌‌The‌‌cycle‌‌can‌‌also‌‌be‌‌explained‌‌by‌‌the‌‌word‌
DISH‌.‌‌The‌‌left‌‌side‌‌of‌‌the‌‌chain‌‌is‌‌mostly‌‌about‌‌the‌s
‌ ocial‌‌factor‌‌‌and‌‌the‌‌right‌‌side‌‌of‌‌the‌‌
chain‌‌is‌‌mostly‌‌about‌‌the‌m ‌ edical‌‌part‌.‌ ‌
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Source:‌‌WUR‌ ‌
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1.1c‌‌Essential‌‌epidemiology‌ ‌
Epidemiology,‌‌therefore,‌‌is‌‌about‌‌measuring‌‌health,‌‌identifying‌‌the‌‌causes‌‌of‌‌ill-health‌‌and‌‌
intervening‌‌to‌‌improve‌‌health.‌ ‌
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For‌‌example,‌‌156‌‌out‌‌of‌‌343‌‌people‌‌who‌‌ate‌‌hot‌‌chicken‌‌became‌‌ill‌‌and‌‌156‌‌÷‌‌343‌‌=‌‌0.45‌‌
=‌‌45%.‌‌​So‌‌45%‌‌of‌‌people‌‌who‌‌ate‌‌hot‌‌chicken‌‌became‌‌sick.‌‌This‌‌is‌‌known‌‌as‌‌the‌a ‌ ttack‌‌
rate‌‌‌for‌‌hot‌‌chicken,‌‌i.e.‌‌45%‌‌of‌‌hot-chicken‌‌eaters‌‌were‌‌‘attacked’‌‌by‌‌food‌‌poisoning.‌ ‌
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For‌‌example,‌‌45%‌‌of‌‌people‌‌who‌‌ate‌‌hot‌‌chicken‌‌became‌‌ill,‌‌compared‌‌with‌‌32%‌‌of‌‌
people‌‌who‌‌did‌‌not‌‌eat‌‌hot‌‌chicken.‌‌Hot-chicken‌‌eaters‌‌were‌‌therefore‌‌1.4‌‌times‌‌(45%‌‌÷‌‌
32%‌‌=‌‌1.4)‌‌more‌‌likely‌‌to‌‌become‌‌ill‌‌than‌‌people‌‌who‌‌did‌‌not‌‌eat‌‌hot‌‌chicken.‌‌This‌‌
measure‌‌gives‌‌us‌‌the‌‌risk‌‌of‌‌sickness‌‌in‌‌hotchicken‌‌eaters‌‌relative‌‌to‌‌non-eaters,‌‌hence‌‌its‌‌
name‌‌–‌‌relative‌‌risk‌.‌ ‌
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Descriptive‌‌epidemiology‌‌‌focuses‌‌on‌‌‘person,‌‌place‌‌and‌‌time’.‌A ‌ nalytic‌‌studies‌‌‌look‌‌for‌‌
associations‌‌between‌‌potential‌‌causal‌‌agents‌‌and‌‌diseases.‌‌Epidemiologists‌‌also‌e ‌ valuate‌‌
new‌‌preventive‌‌measures,‌‌programs‌‌or‌‌treatments‌‌that‌‌are‌‌designed‌‌to‌‌reduce‌‌ill‌‌health‌‌or‌‌
promote‌‌good‌‌health.‌‌They‌‌monitor‌‌the‌‌effectiveness‌‌of‌‌these‌‌‘intervention’‌‌programs‌‌after‌‌
they‌‌have‌‌been‌‌implemented.‌ ‌
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In‌‌conclusion:‌ ‌
Again‌‌we‌‌have‌‌a‌‌vivid‌‌picture‌‌of‌‌a‌‌master‌‌epidemiologist‌‌at‌‌work.‌‌Not‌‌satisfied‌‌that‌‌his‌‌
hypothesis‌‌had‌‌been‌‌adequately‌‌tested,‌‌Snow‌‌identified‌‌the‌‌opportunity‌‌to‌‌conduct‌‌an‌‌even‌‌
more‌‌rigorous‌‌test‌‌–‌‌his‌‌‘Grand‌‌Experiment’‌‌–‌‌and‌‌in‌‌doing‌‌so‌‌he‌‌addressed‌‌the‌‌major‌‌
epidemiological‌‌issues‌‌that‌‌still‌‌concern‌‌us‌‌today.‌‌ ‌‌

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Introduction‌‌Descriptive‌‌Epidemiology‌‌and‌‌Public‌‌Health‌‌(HNH-28303)‌ ‌