Descriptive Epidemiology

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Descriptive Epidemiology

• Tuesday 1/22/02
• PH 2711
• Jan Risser

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Descriptive Epidemiology

• The study of the occurrence of disease or other
  health-related characteristics in human
  populations by
• Age
• Sex
• Race
• Occupation
• Social class
• Geographic location
• From A Dictionary of Epidemiology. Fourth
  Edition. John M Last

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Descriptive Epidemiology

• The major characteristics in descriptive
  epidemiology can be classified under the
  headings
• Person
• Place
• Time

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Descriptive Epidemiology

• Concerned with the study of the distribution of
  disease in population groups
• Systematic summary of the basic data on health
  and the major causes of disease and death

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Descriptive Epidemiology

• Objectives
• to summarize trends in health
• to compare groups
• to provide a basis for planning, provision, and
  evaluation of health services
• to identify problems to be studied by analytic
  methods

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Distribution

• When distribution of rates is not uniform
  according to person, place, and time
• Epidemiologists can identify high-risk groups
• often for prevention purposes
• Generate causal hypotheses
• based on agent-host-environment paradigm

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Person

• Age
• Sex (biological parameters)
• Gender (social parameters)
• race/ethnicity
• Education
• Socio-economic Status

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Descriptive Epidemiology

• Person
• Age often the most important determinant among
  personal characteristics
• Sex differences in morbidity and mortality.
• Males have higher mortality
• Females have higher morbidity
• Race/ethnicity
• Is this a proxy for socio-economic status?

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Death rate per 100,000. 1980-1998 TexasBy Age
and by Sex
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Suicide rate per 100,000. 1980-1998 Texas By
sex and age.
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Emphysema and Bronchitis rates per 100,000.
1980-1998 Texas. By sex and age
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Pertussis
Scarlet Fever
Diphtheria Meningitis Polio
Rubella
Mumps Chickenpox
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Race/ethnic

• How to classify and for what purpose
• Genetics
• Cultural factors
• Proxy for socio-economic status
• Social class
• Prestige
• Wealth
• Power

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Race/ethnicity

• Prior to 1970 census was classified as
• White
• All others (all non-whites)
• Non-whites had marked disadvantage with respect
  to mortality which still persists
• These differences may represent differences
  associated with the environment

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Race/ethnicity

• 1970 Census
• White, non-White
• 1980 and 1990 Census 16 categories 2 write in
• American Indian/Alaskan Native/Aleut
• Asian or Pacific Islander
• White, Black
• Hispanic and Not Hispanic
• 2000 Census 15 categories 3 write-in more
  than 1 answer

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Race/ethnicity

• 2000 Census
• American Indian or Alaska Native
• Asian Asian Indian, Chinese, Filipino,
  Japanese, Korean, Vietnamese
• Pacific Islander Native Hawaiian, Guamanian or
  Charmorro, Samoan, Other Pacific Islander
• White
• Black
• http//www.census.gov/dmd/www/pdf/d61a.pdf

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Race/ethnicity

• Prestige
• Wealth
• Power
• Social Class
• Occupation
• Marital status
• Nativity

• Family size
• Birth order
• Maternal age
• Parental Deprivation

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Mortality by social class in England and
Wales1949 - 1953
SMR ratio for entire population of males aged
20-64 Infant mortality per 1000 live births
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Dental health by family income
Filled Teeth
Decayed Teeth
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Place

• Natural and political boundaries
• Urban/rural
• International Comparisons
• Migrants

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(No Transcript)
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Urban vs. Rural
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Migrant studies

• Study of migrants

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Time

• Secular trends
• changes over a long period of time
• Cyclic changes
• Recurrent alterations in the frequency of disease
• Clusters
• Cohort analysis

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Analysis birth cohort
Does the prevalence of disease decline with age?
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Analysis birth cohort - Survey date
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Analysis birth cohort
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Analysis birth cohort
1960
1950
1920
1940
1930
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Deaths from TB
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Death from TB
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Deaths from TB
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TB by Birth Cohort