- Race
- Radix
- Rahe-Holmes Social Readjustment Rating Scale
- Random
- Random Allocation
- Random-Digit Dialing
- Randomization
- Randomization, Mendelian
- Randomized Controlled Trial (RCT)
- Random Sample
- Random Sampling Variation
- Random Variable
- Random Walk
- Range of Distribution
- Rank
- Ranking Scale
- Rapid Epidemiological Assessment
- Rare-Disease Assumption
- Rate
- Rate Difference (RD)
- Rate-Odds Ratio
- Rate Ratio
- Ratio
- Ratio Scale
- Raw Data
- Reason For Encounter (RFE)
- Recall Bias
- Receiver Operating Characteristic (ROC) Curve
- Recessive
- Recommendations
- Record Linkage
- Recrudescence
- Rectangularization of Mortality
- Recurrence
- Recurrence Risk
- Recurrent Disease
- Reduction
- Reductionism
- Reed-Frost Model
- Reference Population
- Refinement
- Register, Registry
- Registration
- Regressand
- Regression
- Regression Analysis
- Regression Curve, Line, Surface, Plane
- Regression, Logistic
- Regression Model
- Regression to the Mean
- Regressor
- Reinfection
- Reinforcing Factors
- Relapse
- Relationship
- Relative Effect
- Relative Excess Risk (RER)
- Relative Index of Inequality
- Relative Odds
- Relative Poverty Level
- Relative Risk (RR)
- Relative Risk Reduction (RRR)
- Relevance
- Reliability
- Remote Sensing
- Repeatability
- Replacement-Level Fertility
- Replication
- Reporting Bias
- Representativeness
- Repression Bias
- Reproducibility
- Reproductive Isolation
- Reproductive Success
- Reprogramming
- Rescue Bias
- Research
- Research Design
- Research Ethics Board, Committee
- Research Subject
- Reservoir of Infection
- Resilience
- Residual Confounding
- Resolution, Resolving Power
- Resource Allocation
- Response Bias
- Response Rate
- Responsiveness
- Retrolective
- Retrospective Study
- Retrovirus
- Reverse Causation
- Reverse Causation Bias
- Reverse Transcription
- Review Bias
- Review, Systematic
- Ridit
- Ridit Analysis
- Risk
- Risk Assessment
- Risk Assessment Plot
- Risk-Benefit Analysis
- Risk-Benefit Ratio
- Risk Characterization
- Risk Difference (RD)
- Risk Estimation
- Risk Evaluation
- Risk Factor
- Risk Indicator
- Risk Management
- Risk Marker
- Risk Monitoring
- Risk Ratio
- Risk Set
- Robustness
- Rounding
- “Routine” Data, Routinely Collected Data
- Rubric

# Rate

- Source:
- A Dictionary of Epidemiology

- Author(s):
### Miquel Porta

# Rate

A measure of the frequency of occurrence of a phenomenon. In epidemiology, demography, and vital statistics, a rate is an expression of the frequency with which an event occurs in a defined population, usually in a specified period of time. The components of a rate are the numerator, the denominator, the specified time in which events occur, and usually a multiplier, a power of 10, that converts the rate from an awkward fraction or decimal to a whole number.

In vital statistics,

In epidemiology, the denominator is usually Person-time. Physical units other than time may be used for constructing rates; e.g., in accident epidemiology, deaths per passenger-mile is a more meaningful way of comparing modes of transportation.

Other uses of *rate* in epidemiology include: (1) As a wrong synonym for ratio, it refers to proportions as rates, as in the terms *cumulative incidence rate* or *survival rate*. Proportion and Ratio are not synonyms for rate. (2) In other situations, rate refers only to ratios representing relative changes (actual or potential) in two quantities. (3) Sometimes rate is further restricted to refer only to ratios representing changes over time. In this sense, the term *prevalence rate* is to be avoided, because Prevalence cannot (and does not need to) be expressed as a change in time; of course, different prevalence estimates may vary, change, and be compared. In contrast, the force of mortality and the force of morbidity (hazard rate) are proper rates, for they can be expressed as the number of cases developing per unit time divided by the total size of the population at risk.^{1}^{,} ^{2}^{,} ^{3}^{,} ^{5}^{,} ^{197} See also hazard rate.

- Race
- Radix
- Rahe-Holmes Social Readjustment Rating Scale
- Random
- Random Allocation
- Random-Digit Dialing
- Randomization
- Randomization, Mendelian
- Randomized Controlled Trial (RCT)
- Random Sample
- Random Sampling Variation
- Random Variable
- Random Walk
- Range of Distribution
- Rank
- Ranking Scale
- Rapid Epidemiological Assessment
- Rare-Disease Assumption
- Rate
- Rate Difference (RD)
- Rate-Odds Ratio
- Rate Ratio
- Ratio
- Ratio Scale
- Raw Data
- Reason For Encounter (RFE)
- Recall Bias
- Receiver Operating Characteristic (ROC) Curve
- Recessive
- Recommendations
- Record Linkage
- Recrudescence
- Rectangularization of Mortality
- Recurrence
- Recurrence Risk
- Recurrent Disease
- Reduction
- Reductionism
- Reed-Frost Model
- Reference Population
- Refinement
- Register, Registry
- Registration
- Regressand
- Regression
- Regression Analysis
- Regression Curve, Line, Surface, Plane
- Regression, Logistic
- Regression Model
- Regression to the Mean
- Regressor
- Reinfection
- Reinforcing Factors
- Relapse
- Relationship
- Relative Effect
- Relative Excess Risk (RER)
- Relative Index of Inequality
- Relative Odds
- Relative Poverty Level
- Relative Risk (RR)
- Relative Risk Reduction (RRR)
- Relevance
- Reliability
- Remote Sensing
- Repeatability
- Replacement-Level Fertility
- Replication
- Reporting Bias
- Representativeness
- Repression Bias
- Reproducibility
- Reproductive Isolation
- Reproductive Success
- Reprogramming
- Rescue Bias
- Research
- Research Design
- Research Ethics Board, Committee
- Research Subject
- Reservoir of Infection
- Resilience
- Residual Confounding
- Resolution, Resolving Power
- Resource Allocation
- Response Bias
- Response Rate
- Responsiveness
- Retrolective
- Retrospective Study
- Retrovirus
- Reverse Causation
- Reverse Causation Bias
- Reverse Transcription
- Review Bias
- Review, Systematic
- Ridit
- Ridit Analysis
- Risk
- Risk Assessment
- Risk Assessment Plot
- Risk-Benefit Analysis
- Risk-Benefit Ratio
- Risk Characterization
- Risk Difference (RD)
- Risk Estimation
- Risk Evaluation
- Risk Factor
- Risk Indicator
- Risk Management
- Risk Marker
- Risk Monitoring
- Risk Ratio
- Risk Set
- Robustness
- Rounding
- “Routine” Data, Routinely Collected Data
- Rubric