Low Birth Weight Checker
Exact strict-under2500gmeasured low-birthweight definition check. Not fetal estimated-weight diagnosis, gestational maturity, prognosis or claim above-threshold safety.
Description
Low birth weight is conventionally defined as birth weight below 2500 grams.
When to use Low Birth Weight Checker
Use this tool to calculate or review the supplied observations under the stated rules. Establish the observation date, units, measurement context and independently applicable clinical reference or calibrated model.
How to use Low Birth Weight Checker and understand its results
- Establish the observation date, units, measurement context and independently applicable clinical reference or calibrated model.
- Enter independentlyMeasuredBirthWeightGrams, using the field meanings and rules below, then run the tool.
- Read result.belowConventional2500Grams, result.signed2500GramMargin. Use the units and sign conventions below.
- Correct any reported input issue and run again. Before using a successful result, check the stated units, signs, reference scope and observation coverage.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| independentlyMeasuredBirthWeightGrams | Independently measured birth weight grams | number | Required |
Require positive measured birth weight in grams. Return true only for weight<2500 and weight−2500 as the signed margin; exactly 2500 is false.
lowBirthWeight=(grams<2500); signedMarginGrams=grams−2500 Use the matching field units and the exact boundary, ordering and reference rules above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Structured result; its nested fields below contain the actual calculation or selected reference | object |
| result.belowConventional2500Grams | Below Conventional2500 Grams | boolean |
| result.signed2500GramMargin | Signed2500 Gram Margin; preserve the subtraction order and sign defined in the mechanics | number |
{
"input": {
"independentlyMeasuredBirthWeightGrams": 2400
},
"output": {
"result": {
"belowConventional2500Grams": true,
"signed2500GramMargin": -100
}
}
}Limitations and assumptions
Dating evidence, acquisition conditions and applicable clinical references remain independently established. The output describes supplied observations or a conditional model without diagnosing an outcome, choosing a dose or verifying clinical applicability.
Missing required fields, unknown fields, wrong types and violated rules return input issues. Numeric values and outputs must be finite. Extremely large composite outputs are rejected.
Alternative or Complementary methods
For a related step, use Placental Weight Ratio Calculator: Placental weight ratio relates measured placental mass to measured birth mass. For a complementary comparison, use Birth Weight Category Lookup: Conventional birth-weight categories use mass thresholds without determining gestational maturity.
References
-
Low Birth Weight Checker — tool.io
-
Low birth weight: threshold definition — World Health Organization
Similar or alternative tools
- Placental Weight Ratio Calculator
Placental weight ratio relates measured placental mass to measured birth mass.
- Birth Weight Category Lookup
Conventional birth-weight categories use mass thresholds without determining gestational maturity.