Biostatistics Lab

Demography

Demography

The statistical study of human populations, including the size, structure, and distribution of different populations and changes in them.

Population

The number or body of inhabitants in a place belonging to a specific social, cultural, socioeconomic, ethnic, or racial subgroup.

Demographic Analysis

A technique used to understand the age, sex, and racial composition of a population and how it has changed over time through birth, death, and migration.

Population Studies

The scientific study of human populations, including broad population dynamics, fertility and family dynamics, health, aging, mortality, and human capital and labor markets.

Count

The absolute number of a population or any demographic event occurring in a specified area and time period.

Rate

The frequency of demographic events in a population during a specified time period divided by the population "at risk" of the event occurring.

Ratio

The relation of one population subgroup to the total population or to another subgroup.

Proportion

The relation of a population subgroup to the entire population.

Constant

An unchanging, arbitrary number used to express rates, ratios, or proportions in a more understandable fashion.

Cohort Measure

A statistic that measures events occurring to a group of people sharing a common demographic experience over time.

Period Measure

A statistic that measures events occurring to all or part of a population during one period of time.

Population Composition

The description of a population according to characteristics such as age, sex, race, or other factors.

Vital Statistics

Information obtained from vital events such as births, deaths, marriages, and changes in civil status, recorded in a civil register.

Demographic Indicators

Indicators used to measure changes in health or nutritional status indirectly, indicating direction and speed of change and allowing for comparisons between different areas and groups of people.

Mortality Indicators

Indicators used to measure death rates and signal a broad range of health problems, including crude mortality rate, age-specific mortality rate, infant mortality rate, maternal mortality rate, and under-5 mortality rate.

Morbidity Indicators

Indicators used to measure the frequency of illness, disease, injury, and disability in a population, including incidence and prevalence.1. Disability Rates:The International Classification of Functioning, Disability and Health (ICF) defines disability as an umbrella term for impairments, activity limitations and participation restrictions.

Healthcare Delivery Indicators

Indicators that reflect the equity of distribution of health resources in different parts of the country and provision of health care, such as doctor-population ratio, doctor-bed ratio, and population-bed ratio.

Utilization Rates

Actual coverage expressed as the proportion of people in need of a service who actually receive it in a given period, usually a year.

Social and Mental Health Indicators

Indirect measures like indicators of social and mental pathology are relied upon to assess social and mental health, such as acts of violence, crime, suicide, homicide, road accidents, juvenile delinquency, alcohol and drug abuse, smoking, and consumption of tranquillizers.

Environmental Indicators

Indicators that reflect the quality of physical and biological environment in which diseases occur and in which people live.

Socioeconomic Indicators

Indicators that do not directly measure health but are important in the interpretation of healthcare indicators, such as rate of population increase, per capita GNP, level of unemployment, dependency ratio, literacy rates, family size, housing density, and per capita calorie availability.

Health Policy Indicators

Indicators that reflect the allocation of adequate resources to the health sector and political commitment to health, such as proportion of GNP spent on health services, proportion of GNP spent on health-related activities, and proportion of total health resources devoted to primary health care.

Quality of Life Indicators

Indicators that measure physical, mental, and social well-being as perceived by individuals or groups, including happiness, satisfaction, and gratification in various aspects of life.

Overview of Demographic Changes

A discussion on significant and unprecedented demographic shifts, shaping societies and posing policy challenges, particularly in relation to the global increase in the general population and the aging population in wealthier countries.

Drivers of Demographic Change

Various factors that drive demographic changes, including fertility rates, childhood survival rates, age at death, and migration patterns.

Demographic Transition

A shift from high birth and death rates to low birth and death rates as societies develop, significantly impacting population structures and presenting challenges and opportunities.

Population Pyramid Shapes

Different population pyramid shapes representing high fertility, transitioning, and aging populations, showcasing examples from Nigeria, Bangladesh, and Japan.

Demographic Dividend

A period of low dependency ratio that presents an opportunity for economic growth, depending on effective policies to utilize the working-age population.

Implications for Global Population Distribution

The predicted shift in global population distribution, with Africa and Asia becoming major population hubs, and the understanding that the demographic transition is a temporary phenomenon that will eventually stabilize the global population structure.1. Population Census:A comprehensive enumeration of the inhabitants of a country or specific area, gathering demographic details such as age, sex, marital status, education level, economic activity, migration patterns, and more. Conducted every ten years.

Vital Registration

The mandatory recording of vital events such as births, deaths, marriages, and divorces by every citizen. Contributes to demographic data.

Population Register

A continuous and permanent register containing essential information about each citizen, including names, addresses, age, and sex. Acts as a vital source of demographic data for administrative and legal purposes.

Sample Surveys

Collecting information from a representative subset (sample) of the population rather than the entire populace. Allows for focused data collection on specific aspects of the population.1. Implementation:The process of carrying out a survey, including selecting a representative sample and collecting data using questionnaires.

Surveys

Research method that complements census data by providing more frequent or specialized information, helps verify census accuracy, and allows for efficient and cost-effective gathering of demographic insights.

Population Growth

The increase in the number of people living in the world, with the majority residing in Asia and Africa. Factors such as fertility rates and aging populations affect the rate of population growth.

Demographics

The study of population characteristics, including fertility rates, life expectancy, and age structure. Demographics change over time and vary across different regions.

Population Growth and Development

The relationship between population growth and economic development, where development can lead to smaller families and slower population growth. This has implications for poverty reduction, gender equality, and environmental sustainability.

Development and Smaller Families

Economic development can lead to smaller families through factors such as increased education, urbanization, and access to family planning. Family planning programs play a role in promoting smaller families.

Epidemiology

The field of medical science that investigates the distribution and determinants of diseases within populations. John Snow's investigation during the 1854 cholera outbreak in London is a notable example of the power of data analysis and mapping in understanding and combating epidemics.1. Miasma:A mysterious and harmful vapor believed to come from swamps or the ground, traditionally attributed to causing diseases.

John Snow

Epidemiologist who linked contaminated water from a specific pumping station to a cholera outbreak, challenging prevailing beliefs and revolutionizing disease comprehension.

Ontology

The branch of philosophy that deals with how reality is experienced.

Epistemology

The branch of philosophy that deals with how knowledge is acquired.

Methodology

The methods used for scientific study.

Smallpox eradication

The successful elimination of smallpox through mass vaccination programs and a thorough understanding of herd immunity.

Risk factors

Factors that increase the likelihood of developing a disease, such as smoking for lung cancer.

Disease surveillance

Tracking and analyzing data on disease occurrence and patterns within populations.

Diagnostic tests

Tests used to diagnose diseases, evaluated by epidemiologists for accuracy, sensitivity, and specificity.

Trend analysis

Studying changes in disease occurrence over time or across diverse populations to identify patterns and potential causes.

Epidemiology

The study of the distribution and determinants of health-related states and events in specified populations, with a focus on prevention and control.

Natural history of diseases

The progression of a disease from its initial development to its resolution or chronic state.

Subclinical diseases

Diseases that do not present with noticeable signs or symptoms.

Sporadic

Occasional, isolated cases of a disease that occur infrequently and irregularly in a particular population or area.

Endemic

The constant presence of a disease or infectious agent within a specific population, geographic area, or community.

Hyperendemic

The consistent presence of a disease at a higher than expected level within a specific population over a prolonged period.

Epidemic

A sudden and widespread increase in the number of cases of a disease in a particular population or geographic area, exceeding what is normally expected.

Outbreak

A localized increase in the occurrence of a disease in a particular geographic area, community, or population, larger than what is normally expected.

Pandemic

A global outbreak of a disease, spreading over multiple countries or continents and affecting a large number of people.

Sensitivity

The proportion of true positive results in a diagnostic test, expressed as a percentage.

Specificity

The proportion of true negative results in a diagnostic test, expressed as a percentage.

PPV (Positive Predictive Value)

The proportion of positive test results that are true positives, expressed as a percentage.

NPV (Negative Predictive Value)

The proportion of negative test results that are true negatives, expressed as a percentage.

Vital statistics

The branch of biometry that deals with data and the law of human mortality, morbidity, and demography.

De facto census

Counts people based on where they are during the census, even if they're not usually there.

De jure census

Counts people based on where they officially belong, even if they're not there during the census.

Modern census

A thorough survey that collects detailed information about a country's people, homes, and more.

Sample registration survey

A method of collecting population data through a sample of the population.

Registration of live events

Recording of births, deaths, and other significant events in a population.

Institutional records

Records from institutions such as hospitals or schools that provide data on population characteristics.

Demographic analysis

The study of the components of variation and change in demographic variables and the relationship between them.1. Population Studies:The study of relationships between demographic variables and other variables such as social and economic variables.

Tools of Demography

Count, rate, ratio, proportion, constant, cohort, and period measure.

Health Indicators

Valid, reliable, sensitive, specific, feasible, and relevant measures used to assess health.

Measures of Morbidity

Epidemiological measures used to understand disease distribution and outbreak causes related to food.

Study Types

Ecological study, case series, cross-sectional study, case-control study, cohort study, and interventional study.

Meta-Analysis and Systematic Review

Methods to summarize and interpret multiple studies on a particular topic.

Randomized Controlled Trials (RCTs)

Gold standard for testing the efficacy of interventions.

Evidence-Based Medicine (EBM)

Integrating clinical expertise, patient values, and the best available evidence to make informed decisions about patient care.

PICO Method

A systematic approach to formulating research questions.

Disease Frequency Measures

Incidence and prevalence.

Measures of Association

Relative risk (RR) and odds ratio (OR).

Hypothesis Testing

Statistical tests used to evaluate the significance of observed associations between variables.

Historical Significance and Public Health Impact

Notable contributions and examples of epidemiology's role in public health.

Challenges and Advancements

Impact of technology, ethical concerns, and the evolving nature of epidemiology.

Preventive Medicine

The science and art of preventing diseases, prolonging life, and promoting health.

Public Health

Undertakings for the prevention of diseases and the promotion of health that are primarily a community responsibility.

Objectives of Preventive Medicine

Promoting optimum health and having a physically and mentally sound body.1. Prevent departure from health:Being free from any forms of illness.

Prevent disabling illness after the onset of disease in man

Fixing any forms of disability through rehabilitation.

Primary level prevention

Designed to promote general optimum health or specific protection against disease agents or establishment of barriers against agents in the environment.

Secondary level prevention

Accomplished by early diagnosis, prompt and adequate treatment to prevent the spread of the disease and further complications.

Tertiary level prevention

The level where the defect and disability have been fixed, accomplished by rehabilitation.

Local Infection

Invading microorganisms are confined to one area (e.g., wound).

Focal Infection

Microorganisms are confined to one area, which may serve as a source for further dissemination of toxic materials to other parts of the body (e.g., diarrhea).

Systemic or General Infection

General invasion affecting the entire body (e.g., typhoid fever and cancer).

Bacteremia

Presence of bacteria in the bloodstream but no active multiplication (e.g., Influenza and boils).

Septicemia

Invasion of bacteria in the bloodstream with active multiplication of microorganisms (e.g., typhoid fever caused by contaminated foods and drinks).

Pyemia

Presence of pus-forming bacteria in the bloodstream, characterized by the development of abscesses in various organs (e.g., carcinoma).

Sapremia

A form of blood poisoning caused by toxins produced by certain microorganisms (e.g., canned food poisoning).

Toxemia

Condition of illness due to the presence of toxins in the bloodstream, caused by the ingestion of foods contaminated with toxins (e.g., toxemia of pregnancy due to ingestion of poisonous substances).

Endemic disease

A small number of people are affected among the population of a community (e.g., meningococcal meningitis, common colds).

Epidemic disease

When an endemic disease flares up affecting a large number of people and spreads from person to person within a certain community (e.g., diarrhea, measles, chicken pox).

Pandemic

When an epidemic becomes widespread, and the disease is prevalent throughout the entire country (e.g., blood-borne infections, HIV infection).

Etiologic agents

Rickettsia (microorganisms between bacteria and viruses, respond to antimicrobial agents), Viruses (obligate intracellular parasites).