Introduction to Biostatistics

Comprehensive vocabulary flashcards from the Introduction to Biostatistics lecture, covering fundamental definitions, data types, measurement scales, and statistical branches.

Statistics

The science of collecting, organizing, summarizing, analysing, and drawing conclusions from data.

Biostatistics

The science that deals with developing and application of the most appropriate methods for collecting, presenting, analysing, and interpreting data for decision-making in medicine, public health, and biology.

Variable

A characteristic or attribute that can assume different values.

Random variable

Variables whose values are determined by chance and cannot be predicted in advance.

Data

The values (measurements or observations) that the variables can assume.

Data set

A collection of data values.

Raw data

Data in its original form that has not been manipulated for any purpose.

Qualitative data

Nonnumerical information describing categories or characteristics, such as sex or marital status.

Quantitative data

Numerical information that can be measured or counted, such as height and blood pressure.

Discrete data

Countable numbers with no intermediate values, such as the number of children.

Continuous data

Measurable values that can take any value within a range, such as weight.

Scales of measurement

The classification of variables by how they are categorized, counted, or measured; common types include nominal, ordinal, interval, and ratio.

Nominal scale

A measurement scale that classifies data into mutually exclusive categories in which no order or ranking can be imposed.

Ordinal scale

A measurement scale that classifies data into categories that can be ordered or ranked, indicating the direction of difference without precise differences between groups.

Categorical data

A collective term for nominal and ordinal level data, which can be further classified as dichotomous or polychotomous.

Dichotomous (Binary) data

Data that has only two categories or levels, such as dead/alive, passed/failed, or male/female.

Polychotomous data

Data with three or more categories or levels, such as blood type, race, or religion.

Interval scale

A quantitative measurement scale with ordered values and equal intervals, but without a true zero point (zero is arbitrary).

Ratio scale

A quantitative measurement scale with equal intervals and a true zero point that represents the complete absence of the variable.

Independent variable

A variable presumed to cause an effect in another variable; the variable manipulated by researchers in an experiment.

Dependent variable

The variable in which changes result from manipulations of the independent variable.

Probability

The likelihood that an event will occur.

Conditional probability

The probability of an event occurring given that another event has occurred.

Independent events

Events where the occurrence of one does not affect the occurrence of the other.

Dependent events

Events where the occurrence of one event influences the other.

Normal distribution

A symmetrical, bell-shaped distribution common in biological data.

Population

The entire group of interest in a study.

Sample

A group of subjects selected from a population; a subset of a population.

Inference

Reaching a conclusion about a population based on information derived from a sample drawn from that population.

Parameter

A characteristic or numerical value describing a population.

Statistic

A characteristic or numerical value describing a sample.

Reliability

The extent to which results are consistent from repeated experiments or observations (precision).

Validity

The extent to which instruments used in an experiment measure exactly what they are intended to measure (accuracy).

Bias

A systematic error in the design, conduct, analysis, or reporting of a study that leads to an incorrect estimate.

Statistical test

A formal method used to make inferences about a population based on sample data.

Sampling error

The difference that exists between a sample statistic and the corresponding population parameter due to the sampling process.

Descriptive statistics

The branch of statistics involving the collection, organization, summarization, and presentation of data to describe a situation.

Inferential statistics

The branch of statistics used to draw conclusions, make predictions, and generalize from a sample to a population.