Description
Bound secondary cases by that remainder and divide for secondary attack rate.
Epidemiological shares depend on who or what enters each denominator. Tests, distinct people, known-status records and eligible contacts describe different populations; a ratio computed from them is not automatically population risk or an individual diagnosis.
Bound secondary cases by that remainder and divide for secondary attack rate.
When to use this tool
Use Secondary Attack Rate Index Exclusion when you need a stated surveillance or screening count summary.
How to use the tool and how it works
- Enter totalExposed, indexCases, immuneExcluded, secondaryCases. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read susceptibleContacts, secondaryAttackRate. Use the output convention below.
Require positive exposed total and nonnegative index/immune counts with a strictly positive remainder. Bound secondary cases by that remainder and divide for secondary attack rate.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| totalExposed | Total Exposed | Required. Safe integer; minimum 1. |
| indexCases | Index Cases | Required. Safe integer; minimum 0. |
| immuneExcluded | Immune Excluded | Required. Safe integer; minimum 0. |
| secondaryCases | Secondary Cases | Required. Safe integer; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| susceptibleContacts | Susceptible Contacts | Required. Safe integer. |
| secondaryAttackRate | Secondary Attack Rate | Required. Finite number. |
{
"input": {
"totalExposed": 50,
"indexCases": 2,
"immuneExcluded": 8,
"secondaryCases": 10
},
"output": {
"susceptibleContacts": 40,
"secondaryAttackRate": 0.25
}
}Limitations and assumptions
- Index and immune exclusions are assumed disjoint within the supplied exposure cohort. Case ascertainment, susceptibility, causation and clinical status are not 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 appropriate study design and verified case definitions for health interpretation. Address ascertainment, repeated records, missing status, selection and uncertainty before generalizing a descriptive proportion.
References
Similar or alternative tools
- Screening Positive Yield Denominator Choice
Return positives/screened, confirmed/invited and confirmed/positive.
- Vaccination Coverage Known Status Base
Return vaccinated/known and vaccinated/all-records coverage.