Description
Subtract supplied excluded person-days from recorded exposure.
Statistical record calculations depend on risk-set boundaries, cluster assumptions, missingness codes and exposure definitions. Entry can be excluded while exit inclusion is a policy choice, and one design-effect formula assumes equal cluster sizes. A local flag or contribution does not fit a model or establish a clinical result.
Subtract supplied excluded person-days from recorded exposure.
When to use this tool
Use Contribution Person Days Exclusion Offset when you already have recordedPersonDays, excludedPersonDays and need to subtract supplied excluded person-days from recorded exposure.
How to use the tool and how it works
- Enter recordedPersonDays, excludedPersonDays. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read includedPersonDays. Use the output convention below.
Require both amounts>=0; return recorded-excluded without clamping.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| recordedPersonDays | Recorded Person Days | Required. Finite number; minimum 0. |
| excludedPersonDays | Excluded Person Days | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| includedPersonDays | recordedPersonDays-excludedPersonDays; signed discrepancies are retained. | Required. Finite number. |
{
"input": {
"recordedPersonDays": 120,
"excludedPersonDays": 15
},
"output": {
"includedPersonDays": 105
}
}Limitations and assumptions
- Negative discrepancies and fractional person-days are accepted. No exposure, exclusion subset, risk period, study validity or actual contribution is verified.
- 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 the complete study design, data and statistical model for inference. Check censoring, clustering, visit windows, exposure and missingness conventions before combining these terms, and assess uncertainty with the full analysis.
References
Similar or alternative tools
- Person Time Interval At Risk
Calculate overlap duration of supplied risk and observation intervals.
- Survival Entry Exit Order Flag
Check supplied survival entry/exit order and preserve signed duration.