down-probability-maternal-age

Calculate probability of Down syndrom from maternal age.

This is not anymore a good method too calculate the down probability. Consult a specialist.

French version here : Readme FR

Setup

npm i -S down-probability-maternal-age

or yarn

yarn add down-probability-maternal-age

calculate

import { calculate } from 'down-probability-maternal-age';

calculate(20, 3);
// {percent: 0.06626905235255136, decimal: 0.0006626905235255136, perBirth: '1/1509'}

Arguments

• Years : number of years of live,
• Months : number of month of live in current year.

In the example above, mother has 20 years and 3 months.

Returns

An object containing :

• Probability in percent,
• Probability in float,
• Syndrome's frequency.

In this sample, frequency is about one case for each 1509 births.

calculateFromMonths

import { calculateFromMonths } from 'down-probability-maternal-age';

calculateFromMonths(526);
// {percent: 3.3333333333333335, decimal: 0.03333333333333333, perBirth: '1/30'}

Argument

Here, age of mother is only in months.

So in this sample, mother has 526 months, corresponding to 43 yeas and 10 months.

Returns

This function is a proxy of function calculate. So the return is exactly the same.

For the example above, frequency is about 1 case for each 30 births.

License

WTFPL