Description
Measure person-time inside the overlap of entry/exit and observation windows.
Epidemiological reporting depends on case-definition versions, observation windows, censoring, person/test denominators and time-bin boundaries. Missing and indeterminate results differ, while multiple tests can belong to one person. Local record arithmetic does not diagnose infection, establish transmission or select a public-health rule.
Measure person-time inside the overlap of entry/exit and observation windows.
When to use this tool
Use Person Time Entry Exit Overlap when checking the stated benign surveillance record, time, exposure or denominator convention.
How to use the tool and how it works
- Enter entryTime, exitTime, windowStart, windowEnd. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read includedPersonTime. Use the output convention below.
Require exit>=entry and windowEnd>=windowStart. Return max(0,min(exit,windowEnd)-max(entry,windowStart)) as included person-time.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| entryTime | Entry Time | Required. Finite number. |
| exitTime | Exit Time | Required. Finite number. |
| windowStart | Window Start | Required. Finite number. |
| windowEnd | Window End | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| includedPersonTime | Included Person Time | Required. Finite number. |
{
"input": {
"entryTime": 2,
"exitTime": 8,
"windowStart": 4,
"windowEnd": 10
},
"output": {
"includedPersonTime": 4
}
}Limitations and assumptions
- Touching bounds contribute zero duration; one interval term does not compute incidence, assess exposure or verify follow-up.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use verified source records, current authoritative definitions and appropriate complete epidemiological/statistical methods with qualified public-health interpretation for actual decisions.
References
Similar or alternative tools
- Sentinel Site Reporting Exposure Hours
Calculate reporting exposure from supplied sentinel-site hours.
- Surveillance Week Partial Day Denominator
Convert complete days and additional hours to supplied day-equivalent exposure.