Description
Calculate signed lesion-axis change and its fraction of baseline.
Oncology records distinguish individual lesion measurements, missingness reasons, source coding, visit timing and assigned treatment-line labels. A signed axis change is not automatically a response category or stage. Clinical endpoints and regimen records require their verified definitions; local arithmetic and transcription do not determine diagnosis, outcome or treatment.
Calculate signed lesion-axis change and its fraction of baseline.
When to use this tool
Use Tumor Axis Measurement Change when you already have baselineAxis, followupAxis and need to calculate signed lesion-axis change and its fraction of baseline.
How to use the tool and how it works
- Enter baselineAxis, followupAxis. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read absoluteChange, fractionalChange. Use the output convention below.
Require baselineAxis>0 and followupAxis>=0; absoluteChange=followup-baseline and fractionalChange=(followup-baseline)/baseline.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| baselineAxis | Baseline Axis | Required. Finite number; strictly above 0. |
| followupAxis | Followup Axis | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| absoluteChange | Signed followup-baseline in the axis length unit; the field name does not mean abs(difference). | Required. Finite number. |
| fractionalChange | Signed change/baseline, a decimal fraction rather than a percentage number. | Required. Finite number. |
{
"input": {
"baselineAxis": 20,
"followupAxis": 15
},
"output": {
"absoluteChange": -5,
"fractionalChange": -0.25
}
}Limitations and assumptions
- Here absoluteChange means dimensional signed difference, not its absolute magnitude; no target selection, response category, staging or treatment decision is inferred.
- 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 source-defined lesion, registry and outcome criteria with verified records for an assessment. Keep missingness reasons, measurement axes and assigned treatment-line wording explicit; a single signed dimension change or event-date token does not establish response or stage.
References
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