Prepatent Detection Interval
Bracket observed prepatent detection delay from estimated infection and last-negative/first-positive observations.
Description
An infection-detection interval can be bounded by a last negative observation and first positive observation after a known infection time.
An infection-detection interval can be bounded by a last negative observation and first positive observation after a known infection time. The two observations leave an interval rather than an exact onset.
The tool returns firstPositiveIntervalDays (first positive interval days); lastNegativeIntervalDays (last negative interval days). Input measurements and model parameters are supplied by the caller; the tool computes the stated summary rather than acquiring those measurements.
When to use Prepatent Detection Interval
Use Prepatent Detection Interval when you already have infectionDay, firstPositiveDay, lastNegativeDay and want firstPositiveIntervalDays, lastNegativeIntervalDays. This is useful for checking a supplied calculation, documenting a measurement convention, or comparing observations prepared on the same basis.
How to use Prepatent Detection Interval and understand its results
- Enter infectionDay, firstPositiveDay, lastNegativeDay 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 firstPositiveIntervalDays, lastNegativeIntervalDays. 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 |
|---|---|---|---|
| infectionDay | Infection day | number | Required |
| firstPositiveDay | First positive day | number | Required |
| lastNegativeDay | Last negative day | number | Required |
Require a nonnegative infection day, a last negative day at or after infection, and a first positive day strictly after the negative observation.
lower delay = lastNegativeDay − infectionDay; upper delay = firstPositiveDay − infectionDay The symbols refer to the supplied quantities or generated values described above; unit conversions and comparison boundaries follow the stated implementation.
{
"input": {
"infectionDay": 2,
"firstPositiveDay": 12,
"lastNegativeDay": 9
},
"output": {
"firstPositiveIntervalDays": 10,
"lastNegativeIntervalDays": 7
}
}Limitations and assumptions
The infection time and test results must already be established. These bounds do not distinguish biological maturation from assay detection limits.
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
Surveillance Followup Years: Schedule surveillance calendar years using caller-defined offsets after treatment completion. Gametocyte Clearance Followup: Track first observed zero gametocyte count and subsequent rebound in an ordered follow-up series.
Methodological background: DPDx: diagnostic procedures.1
References
-
DPDx: diagnostic procedures — Centers for Disease Control and Prevention
Similar or alternative tools
- Surveillance Followup Years
Schedule surveillance calendar years using caller-defined offsets after treatment completion.
- Gametocyte Clearance Followup
Track first observed zero gametocyte count and subsequent rebound in an ordered follow-up series.