Biostatistics and Epidemiology - Lecture Notes

Practice flashcards covering key biostatistics and epidemiology concepts from the notes, in a question-and-answer format.

What are the two main branches of statistics?

Descriptive statistics and inferential statistics.

Descriptive statistics

To summarize and present data in a form that makes them easier to analyze and interpret.

Inferential statistics

To generalize conclusions about a target population from results obtained from a sample.

Why is biostatistics important?

It is a tool in decision making for better clinical decisions and improved patient care and outcomes.

Variable

A phenomenon whose values or categories differ from person to person; information about these variables is captured as data.

Data

All information regarding all the variables in the study.

What is the independent variable?

The predictor or experimental variable that causes change in the dependent variable; usually occurs earlier in time and can be manipulated.

What is the dependent variable?

The outcome variable that is measured to assess the effect of the independent variable.

In a study with Shoes (casual, running, boots) and Time, which is the IV and DV?

IV = Shoes; DV = Time.

In the study of The number of cars sold and the price of the car, which is the IV and DV?

IV = Price of the car; DV = Number of cars sold.

In the study 'Predict the value of sunlight on the growth of daisies,' identify the IV and DV.

IV = Value of sunlight; DV = Growth of daisies.

Identify the variables in the statement: 'People who attend church regularly are more likely to oppose abortion.'

Independent variable: church attendance regularity; Dependent variable: opposition to abortion.

What is qualitative (categorical) data?

Non-numerical data; data based on categories (e.g., colors, labels, yes/no).

What is quantitative (continuous) data?

Numerical data that are measurable; can be discrete or continuous.

What is nominal level of measurement?

Categorical data with no intrinsic order.

What is ordinal level of measurement?

Categorical data with a meaningful order or ranking.

What is interval level of measurement?

Numerical data with equally spaced units but no true zero point.

What is ratio level of measurement?

Numerical data with equally spaced units and a true zero point.

Give examples of interval and ratio scales.

Interval: temperature; Ratio: length, weight, money.

What are the three elements of demographics?

Size, composition/structure, distribution.

What is descriptive statistics?

Procedures that organize and describe data from a sample or population.

What is inferential statistics?

Logic and procedures to make predictions or inferences about a population from a sample.

What is the difference between population and sample?

Population is the entire group of interest; sample is a subset used to infer about the population.

What is a ratio?

A relative magnitude of two quantities (a/b).

What is a rate?

An event occurring in a defined population over a specified period of time.

What is a proportion?

A part relative to the whole; numerator is part of the denominator.

What are the four scales of measurement?

Nominal, Ordinal, Interval, Ratio.

What does demography study and what are its three elements?

Demography studies the science of population; size, composition/structure, and distribution.

What is descriptive statistics vs inferential statistics in one line?

Descriptive describes data; inferential makes inferences about a population from a sample.

In a rate or proportion, how are the numerator and denominator related?

The numerator is a part of the denominator.