Description
Return adjusted denominator and followed/adjusted time.
Longitudinal ageing research links observations to people, waves, and sources. A person may appear in multiple records, so distinct-person coverage and record counts answer different questions and require explicit duplicate rules.
Return adjusted denominator and followed/adjusted time.
When to use this tool
Use Cohort Followup Exposure Share when you need a record-coverage or source-support diagnostic in ageing research.
How to use the tool and how it works
- Enter followedTime, eligibleTime, excludedTime. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read denominator, share. Use the output convention below.
Require eligibleTime greater than nonnegative excludedTime and followedTime within their remainder. Return adjusted denominator and followed/adjusted time.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| followedTime | Followed Time | Required. Finite number; minimum 0. |
| eligibleTime | Eligible Time | Required. Finite number. |
| excludedTime | Excluded Time | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| denominator | Denominator | Required. Finite number. |
| share | Dimensionless share on the numerator and denominator basis stated above. | Required. Finite number. |
{
"input": {
"followedTime": 60,
"eligibleTime": 100,
"excludedTime": 20
},
"output": {
"denominator": 80,
"share": 0.75
}
}Limitations and assumptions
- Durations share units and exclusions are supplied; no attrition correction, survival model, response quality, or clinical interpretation is performed.
- 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
Review the original study design, identifiers, and missing-data definitions. Use the full longitudinal dataset for inference rather than treating a local coverage flag as evidence of representativeness.
References
Similar or alternative tools
- Aging Cohort Selective Attrition Share
Return each retention rate, their difference, and retained-group share among all retained.
- Cohort Age Period Birth Year Identity
Return periodYear-ageYears and subtract recordedBirthYear for identityResidual.