Microfilaremia Prevalence Screen
Screen observed microfilaremia prevalence against a supplied limit; does not certify elimination.
Description
Microfilaremia prevalence is the fraction of examined individuals testing positive.
Microfilaremia prevalence is the fraction of examined individuals testing positive. A strict threshold comparison is a separate operation from estimating the proportion.
The tool returns observedPrevalencePercent (observed prevalence percent); belowThreshold (below threshold). Input measurements and model parameters are supplied by the caller; the tool computes the stated summary rather than acquiring those measurements.
When to use Microfilaremia Prevalence Screen
Use Microfilaremia Prevalence Screen when you already have microfilaremiaPositive, totalExamined, maximumPrevalenceFraction and want observedPrevalencePercent, belowThreshold. This is useful for checking a supplied calculation, documenting a measurement convention, or comparing observations prepared on the same basis.
How to use Microfilaremia Prevalence Screen and understand its results
- Enter microfilaremiaPositive, totalExamined, maximumPrevalenceFraction using the field table below. Match the units, ordering and data boundaries described in the calculation.
- Run the tool after checking the stated bounds and matching paired observations or categories. A malformed request gives a tool error rather than a usable measurement.
- Read observedPrevalencePercent, belowThreshold. Use the calculation and interpretation below to distinguish amounts, ratios, signs and decision flags where applicable.
- Review the supplied parameters and assumptions before using the result in a report or comparing it with another observation.
| Input field | Meaning | Value type and bounds | Requirement |
|---|---|---|---|
| microfilaremiaPositive | Microfilaremia positive | integer | Required |
| totalExamined | Total examined | integer | Required |
| maximumPrevalenceFraction | Maximum prevalence fraction | number | Required |
Validate nonnegative integer positives against a positive examined count, then compare the fraction with the caller-supplied threshold. Equality does not pass.
prevalence = positives/examined; belowThreshold = prevalence < threshold The symbols refer to the supplied quantities or generated values described above; unit conversions and comparison boundaries follow the stated implementation.
{
"input": {
"microfilaremiaPositive": 3,
"totalExamined": 1000,
"maximumPrevalenceFraction": 0.01
},
"output": {
"observedPrevalencePercent": 0.3,
"belowThreshold": true
}
}Limitations and assumptions
No confidence interval, test sensitivity adjustment or survey-design correction is applied. The caller chooses the appropriate surveillance threshold.
Numerical inputs must be finite. The tool checks its declared input shape and calculation constraints; those checks do not verify the quality, calibration or representativeness of the supplied observations.
Alternative or Complementary methods
Survey Positive Count Gate: Compare a transmission-assessment survey positive count with a caller-provided design-specific limit. Day Three Positivity Screen: Screen observed day-three positivity against an explicit surveillance cutoff; does not establish resistance.
Methodological background: Monitoring drug coverage for preventive chemotherapy.1
References
-
Monitoring drug coverage for preventive chemotherapy — World Health Organization
Similar or alternative tools
- Survey Positive Count Gate
Compare a transmission-assessment survey positive count with a caller-provided design-specific limit.
- Day Three Positivity Screen
Screen observed day-three positivity against an explicit surveillance cutoff; does not establish resistance.