Biostatistics and Epidemiology Prelim Examination

Health Data Management

• Refers to the process of collecting, storing and validating health related data to improve decision making in healthcare and public health.

CDC 2012

• Health data provides a factual basis for decision making in public health through surveillance, epidemiologic investigation, and monitoring of health indicators.

CHED Memo No.13 (2017)

• Emphasizes that Medical Technology students must develop competencies in data handling, data analysis, and health informatics as part of the professional core courses

Demographic

• These are basic descriptive data about a patient or population.

• Describes Population

• Examples: Age, Gender, Residence

Clinical

• These are data related to the patient's medical history, symptoms, diagnosis, and treatment.

• Diagnostic Monitoring

• Examples: Blood Pressure, Glucose Level

Epidemiology

• These are population-level data used to understand disease patterns, causes, and distribution.

• Health Trends

• Examples: Incidence and Prevalence

Operational

• These are data related to the operation and workflow of the laboratory and healthcare facility.

• Workflow analysis

• Examples: Lab test turnaround times

Prevalence

• The total number of the people in a population who have a specific disease.

Incidence

• The rate of new cases of a disease or condition that develop in a specific population over a defined period of time.

Data Validation

• Restricts invalid data entry

Pivot Tables

• Summarize large datasets

Charts

• Visualize trends (e.g., line chart of infection rates)

Microsoft Excel

• Data entry templates for survey or lab records

• Built in formulas for statistical summaries

• Charts for visual trends in infection rates, demographics, etc

JASP

• GUI based no coding needed

• Construct descriptive and inferential stats: mean, t-tests, ANOVA

• Produces clean tables and graphs(APA FORMAT READY)

• Useful for MedTech students to practice hypothesis testing

EPI INFO

• Developed by the CDC for epidemiologic data

• Data entry forms for surveys (e.g., COVID19 case tracking)

• Has built-in mapping and outbreak investigation tools

• Ideal for community health data collection projects

Data Entry

• Is the process of transferring collected information into digital format.

Data Cleaning

• Ensures the accuracy and quality of data by removing Errors (e.g., “Malee” instead of “Male”) Duplicates Inconsistent formats Missing values

Frequency Distribution Table

• Is a table that shows the number of occurrences (frequency) of each unique value in a data set

• It helps Identify patterns and organizes raw data into a more understandable format

Qualitative

• Describes categories or groups(e.g., blood type, gender)

Quantitative

• Data that can be measured

Nominal

• No natural order (e.g., blood type).

Ordinal

• With natural order (e.g., cancer stages).

Discrete

• Countable values (e.g., number of hospital visits).

Continuous

• Any value within a range (e.g., height, BP)

Bar Graph

• Used to display and compare the frequency or proportion of different categories of data

Pie Chart

• Represents Data as a circle divided into slices where each slice’s size is proportional to the percentage it represents.

Histogram

• Similar to bar charts, but they are used for continuous data, showing the distribution of numerical data.

Frequency Polygon

• A type of line graph that represents the distribution of a dataset. It is constructed by plotting points that represent the frequencies of class intervals and connecting those points with straight lines.

Stem and Leaf Plot

• A method for displaying quantitative data that preserves the original value set while showing the distribution.

Box and Whisker Plot

• also known as plot box, is a graphical representation of a dataset’s distribution based on five summary statistics: minimum, first quartile Q1, Median Q2, Third Quartile Q3, and Maximum.

Mean

• Calculated by summing all data values and dividing by the number of values

• It is sensitive to outliers

Median

• The middle value in an ordered dataset

• If there is an even number of values, it is the average of the two middle values.

• More resistant to outliers than the mean

Mode

• The value that appears most frequently. A dataset can be unimodal, bimodal, or multimodal

• Useful for categorical data.

Health Indicators

• Are a specific, measurable, or statistics that describe the health status of a population.

• Usually Numerical measures which help compare the targeted or expected results of health programs

• An indicator may provide a direct estimate of the underlying condition of interest.

Valid

• The indicator measures what is supposed to be measured

• Example: person’s wealth : Net income

Reliable

• The indicator will have the same value even if it is measured by other people at different times under similar conditions

• Example: indicator of the anemia status of pregnant woman: Hemoglobin Level

Sensitive

• Able to detect small changes in the phenomenon being measured in a significant way

• Example: a child’s nutritional status: Weight

Specific

• The indicator reflects changes only in the situation concerned

• Example: a person’s maturity: Age

Feasible

• Collection of data to determine its value if technically, financially, and operationally possible

• Example: A finger-prick test to measure blood sugar levels in a rural clinic is a good indicator for diabetes monitoring

Census

• Complete count of the population of a given place or an entire country

Vital Registration System

• Requires basic and compulsory registration of all births, deaths and marriages occurring in the country

• It was legally instituted in the country on February 27, 1931

• PSA is in-charge of the system

• Main problem: under-registration of births and death

National Health Information System

• an organized and integrated network of resources, processes, and technology that collects, processes, and disseminates health-related data to improve population health and support evidence-based decision-making by policymakers and healthcare practitioners

Field Health Service Information System

• Intended to address the short-term needs of DOH and LGU staff with managerial or supervisory functions in facilities and program areas.

• Provides summary on health service delivery and selected program accomplishment indicators

• Programs available, vaccines, malnourishment, death rate and birth rate

SPEED

• Surveillance in post-extreme emergencies and disasters

ONEISS

• Online National Electronic Injury Surveillance System

PhilMIS

• Phil. Malaria Information System

National Demographic and Health Survey

• Collecting accurate and nationally representative data on health, population and nutrition in developing countries funded by USAID

• Started in 1984 and has covered 90 countries including Philippines

• mportant in policy making, program planning, monitoring and evaluation of programs

Multiple Indicator Cluster Surveys

• Series of household surveys conducted by • UNICEF covering important indicators describing the situation of women and children

• First was conducted in 1995

Young Adult Fertility and Sexuality Study

• Series of national surveys on Filipino youth aged 15-24

• One of primary sources on sexual and non-sexual risk behaviors and its determinants in the Philippines.

Health status indicators

• measure health outcomes and/or their risk factors

• Illnesses, injury, death, and disability

• Personal, environmental

Health service performance indicators

• measure aspects of the performance of health services or public health programs

• checking utilization, accessibility and quality

Crude death rates

• The total amount of death in a population

• Describes the total population which is used as the denominator in the computation

Age Specific rates

• Measures the frequency of an event (like a disease, death, or birth) within a specific age group of a population

• Describes only a specific sub group of the total population being considered.

Mid-year population

June or July

Point in time

• occurred during the specific point in time being considered a day

• • E.g: Outbreak or Epidemic and Diarrhea

Period in time

• occurred over a period of time

• Prevalence of diabetes from January to December 2020

Prevalence time

• occurred during the specific point in time being considered

Incidence time

• occurred over a period of time

Input indicators

• resources needed to deliver the essential services to the population or to achieve project objectives

• Ex. Work forces, volunteers, funds, materials, equipment

Output indicators

• Direct products of project activities. Generally in the form of activities and processes undertaken.

• Direct products or activities

• Ex. program itself, size and scope

Outcome indicators

• immediate result of the services or activities implemented

• Immediate result of activities

• changes (easily achievable)

• Ex. -increased knowledge

Impact indicators

• intended or unintended long-term organizational/community changes

• long term community changes after a year

• Ex .lowering of rates of diseases

Total Fertility Rate

• the average number of children a woman would have in her lifetime if she lived through her reproductive years and experienced the current age-specific fertility rates

• of children who will be born per woman if she pass through the childbearing years bearing children

Crude Birth rate

• Total # of children born per 1000 population in a given place and time

General Fertility Rate

• measures the number of live births per 1,000 women of reproductive age (typically 15-44 or 15-49) in a given year

Age-specific fertility rate

• # of children born per 1000 women in a particular age group

• measures fertility level of each sub-group of women according to age

Total fertility rate

• # of children who will be born per woman if she pass through the childbearing years bearing children

Period Prevalence

• equal to the prevalence at the beginning of the period plus the new cases and recurrences during the said period

• useful for quantifying diseases frequency - Difficulty in defining onset of disease

• Difficulty on determining whether the disease is present or absent in a given day

Number of years life lost

YLL

Number of years lived with disability

YLD

Specific Mortality Rate

• measures the force of mortality in specific subgroups of the population

Cause of Death Rate

• mortality rate from specific diseases or conditions

• used in determining the leading cause of mortality

Infant Mortality Rate

• useful indicator of a country’s level of health development

• component of Physical Quality Life Index

• can be artificially lowered by improving birth registration

Neonatal mortality ratio

• include deaths in the first 28 days of life

Post Neonatal mortality ratio

• include deaths after 28 days of life but before 1 year

Maternal Mortality Ratio

• measures occurrence of maternal deaths

• “death while pregnant or within 42 days of termination of pregnancy”- WHO

• reflects level of obstetric risk in a population

• ideal denominator: Number of pregnancies or Live Births

. Proportionate Mortality Ratio

• measures the proportion of the total deaths occurring in a particular population group or from a particular case

• difference with specific mortality ratio

• denominator used is the total number of deaths and NOT midyear population

Case Fatality Rate

• high CFR means disease is fatal

Under-five Mortality Ratio

• risk of a child born in a specific year or period dying before reaching the age of five

Life Expectancy at Birth

• Ave. no. of years that the newborn is expected to live if the current mortality rates continue to apply

• reflects the overall mortality level of a population

Absolute Numbers

• Simple count of the number of persons, houses or events being considered

Ratios

• Result of dividing one number by another

Proportion

• special kind of ratio wherein the numerator is part of the denominator

• When multiplied by 100, it is called as percentage

Rate

• measures how fast an event occurs over time or space

• expressed in terms of the frequency of occurrence of events

• common example in health is the incidence rate of a disease.

Demography

-The scientific study of human populations

Natality

• Birth

Mortality

• Death

Migration

• moving in and out

De Facto Method

• people are counted or allocated to the area where they were physically present at the time of the census

De Jure Method

• people are counted or allocated to the place of their usual residence

Population Composition

• Determines the number of percentage of the population according to the categories of important sociodemographic economic variables

• The most basic description of the population composition is according to age and sex.

Birth rate

• # of births per 1000 population

Death rate

• # of deaths per 1000 population

Emigration

• number of people leaving the country

Immigration

• number of people moving in to the country

Median Age

• the age below which we have 50% of the population

• The lower the number the younger the population, the higher the number the older the population

Age dependency ratio

• indicator of age- induced economic drain on human resources

• Children (0-14yo) -Dependents (No income)

• Elderly (≥65yo) – Dependents (No income)

Sex ratio

• computed by dividing the number of males by the number of females using a factor of 100

• Interpreted as the number of males for every 100 females in the population

The Population Pyramid

• Graphical presentation of the age and sex structure

• Special type of histogram: male is shown at the left and female at the right –Youngest age group is the base and the oldest is the top

Population Estimation

• Computation of future changes in population numbers, given certain assumptions about future trends in the rates of fertility, mortality, and migration.