Pathology Prevalence Per Skeleton

Summarize caller-observed skeletal pathology prevalence and Wilson binomial interval on assessable skeletons, retaining unassessable coverage; not living-population disease prevalence or clinical diagnosis.

Description

Observed skeletal pathology prevalence is conditional on which skeletons can be assessed.

Observed skeletal pathology prevalence is conditional on which skeletons can be assessed. A binomial interval describes sampling variation among assessable observations, while unassessable material remains a separate coverage measure.^[1]

When to use Pathology Prevalence Per Skeleton

Use this tool to summarize caller-observed skeletal pathology prevalence and Wilson binomial interval on assessable skeletons, retaining unassessable coverage; not living-population disease prevalence or clinical diagnosis.

Prepare the artifact, site or survey measurements and any independently established calibration or model choices. Keep paired observations aligned and confirm units and coordinate conventions.

How to use Pathology Prevalence Per Skeleton and understand its results

Prepare the artifact, site or survey measurements and any independently established calibration or model choices. Keep paired observations aligned and confirm units and coordinate conventions.
Enter affectedObservableSkeletonCount, unaffectedObservableSkeletonCount, unassessableSkeletonCount, normalQuantileForInterval using the field table and calculation rules, then run the tool.
Read observablePrevalence, unassessableFraction, wilsonInterval. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
affectedObservableSkeletonCount	Affected observable skeleton count	integer	Required
unaffectedObservableSkeletonCount	Unaffected observable skeleton count	integer	Required
unassessableSkeletonCount	Unassessable skeleton count	integer	Required
normalQuantileForInterval	Normal quantile for interval	number	Required

Enter nonnegative integer affected, unaffected and unassessable skeleton counts and a positive normal quantile. Assessable total n must be positive. Calculate prevalence, unassessable fraction of the full inventory, and a Wilson interval with half-width z√[p(1−p)/n+z²/(4n²)]/(1+z²/n), clipped to [0,1].

p = affected/(affected+unaffected); Wilson center = [p+z²/(2n)]/(1+z²/n)

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
observablePrevalence	Observable prevalence	number
unassessableFraction	Unassessable fraction	number
wilsonInterval	Wilson interval	list of number

json

{
  "input": {
    "affectedObservableSkeletonCount": 10,
    "unaffectedObservableSkeletonCount": 30,
    "unassessableSkeletonCount": 10,
    "normalQuantileForInterval": 2
  },
  "output": {
    "observablePrevalence": 0.25,
    "unassessableFraction": 0.2,
    "wilsonInterval": [
      0.1402056387535159,
      0.40524890670102953
    ]
  }
}

Limitations and assumptions

The quantile and classifications are supplied. The interval assumes binomial observations and does not correct preservation, selection or correlated individuals. This is archaeological observed prevalence, not a diagnosis or living-population disease estimate.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Enamel Hypoplasia Band Count Tool: Tabulate independently identified enamel bands with tooth observability and crown-length exposure; multiple teeth may record the same episode and counts are not distinct stress events or diagnoses. For a complementary task, use Cut Mark Count Per Bone Tool: Distinguish count per examined bone, marked-bone prevalence and surface-standardized cut-mark density; observed mark identification remains caller supplied, not inferred butchery behavior.

References

Pathology Prevalence Per Skeleton — tool.io

Similar or alternative tools

Enamel Hypoplasia Band Count Tool
Tabulate independently identified enamel bands with tooth observability and crown-length exposure; multiple teeth may record the same episode and counts are not distinct stress events or diagnoses.
Cut Mark Count Per Bone Tool
Distinguish count per examined bone, marked-bone prevalence and surface-standardized cut-mark density; observed mark identification remains caller supplied, not inferred butchery behavior.