Calculator Inputs
Use the fields below to estimate detection strength, missed cases, and progress toward a target detection rate.
Example Data Table
This example shows how reported cases compare with estimated totals and how target planning changes across different populations.
| Scenario | Reported Cases | Estimated Cases | Population | Months | Target % | Adjustment Factor |
|---|---|---|---|---|---|---|
| District A | 1850 | 2500 | 150000 | 12 | 90 | 1.00 |
| District B | 920 | 1400 | 98000 | 12 | 85 | 1.05 |
| District C | 310 | 700 | 55000 | 6 | 80 | 1.10 |
Formula Used
Case Detection Rate (%) = (Adjusted Detected Cases ÷ Estimated Total Cases) × 100
Adjusted Detected Cases = Reported Cases × Underreporting Adjustment Factor
Missed Cases = Estimated Total Cases − Adjusted Detected Cases
Additional Cases Needed = ((Target Rate ÷ 100) × Estimated Total Cases) − Adjusted Detected Cases
Notification Rate per 100,000 = (Reported Cases ÷ Population) × 100,000
These formulas help compare observed surveillance performance against an expected disease burden. They are useful for program monitoring, district comparisons, and resource planning.
How to Use This Calculator
- Enter the number of reported or notified cases collected by your surveillance system.
- Add the estimated total number of cases for the same location and period.
- Input the population size to produce rates per 100,000 people.
- Set the analysis period in months to estimate average monthly detection.
- Choose a target detection rate to compare current performance against a benchmark.
- Apply an underreporting factor if you want to adjust detected cases for known reporting losses.
- Press the calculate button to show the results above the form and review the interpretation.
- Use the export buttons to save a CSV summary or a PDF report for sharing.
Frequently Asked Questions
1. What does case detection rate measure?
It measures how many estimated cases were actually found and reported by a detection or surveillance system during a defined period.
2. Why are estimated cases needed?
Reported cases alone show activity, but estimated cases provide the denominator needed to judge whether detection is weak, moderate, or strong.
3. What is an underreporting adjustment factor?
It adjusts reported cases upward when audits or external studies suggest that some detected cases were never formally reported.
4. Can the rate exceed 100%?
Yes. This may happen when estimates are low, reports include backlog cases, or case finding improves faster than expected burden estimates.
5. What does missed cases mean here?
Missed cases represent the difference between estimated total cases and adjusted detected cases, showing the portion not yet captured.
6. Why include population and monthly outputs?
They support fair comparison across districts, facilities, or campaigns by normalizing case counts and showing average detection pace.
7. Is this calculator useful for planning?
Yes. It highlights shortfalls, estimates additional cases needed, and helps teams set realistic detection improvement targets.