1. What is Incidence and Prevalence?

Incidence measures the occurrence of new cases of a disease in a population during a specific time period, while prevalence measures the proportion of a population that has a condition at a specific point in time.

2. How Does the Calculator Work?

The calculator uses these fundamental epidemiology equations:

Where:

• New Cases — Number of newly developed cases during the time period
• Population at Risk — Number of people who could develop the disease
• Total Cases — All current cases (new and existing)
• Population — Total number of people in the group being studied

3. Importance of These Measures

Details: Incidence helps identify risk factors and causes of disease, while prevalence helps understand the overall disease burden and plan healthcare resources.

4. Using the Calculator

Tips: Enter whole numbers for all fields. Population at risk and total population must be greater than zero. Results are displayed as decimal values.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between incidence and prevalence?
A: Incidence measures new cases over time, while prevalence measures all current cases at a point in time.

Q2: How should I interpret the results?
A: Multiply by 100 to convert to percentage. For rates per 1,000 or 100,000, multiply by those numbers respectively.

Q3: What time period does incidence cover?
A: Incidence typically covers a specific period (e.g., one year). Ensure your new cases data matches your chosen time frame.

Q4: Can prevalence be greater than incidence?
A: Yes, for chronic diseases where cases accumulate over time (like diabetes), prevalence is often much higher than incidence.

Q5: What if my population at risk equals total population?
A: This is common for general population studies where everyone is theoretically at risk.