Add a Perfectly option for FAMs
B-u-g-e opened this issue · comments
What the value should be isn't obvious. There are a lot of different methods. There are a lot of different studies of the methods giving various numbers.
The Lactation Amenorrhea Method (LAM) has up to 92%-100% effectiveness according to some sources:
https://www.ncbi.nlm.nih.gov/books/NBK546661/
Others say 98%:
https://www.nhs.uk/conditions/contraception/natural-family-planning/
Though maybe that method should be ignored because it requires you to have a newborn, meaning most people are unable to use it.
Some sources say the Sympto-thermal/Symptothermal method has 99.6% effectiveness with perfect use:
https://www.aafp.org/afp/2012/1115/od1.html
Others say 98%:
https://www.ncbi.nlm.nih.gov/books/NBK546661/
This site simply says 99% without naming a method:
https://www.nhs.uk/conditions/contraception/natural-family-planning/
Adding a separate entry for LAM may be a different feature request, I'm inclined to hold off on that one for now. As you noted it requires you to already have a newborn. I'm open to adding it, but I think improving the more general case is a better focus for now.
The 76% I currently have on the site is pulled from Planned Parenthood (I err'd on the low end rather than the high end, as it seems to me to be better to be pessimistic when surfacing these numbers).
My current thinking is to add a 3-button toggle option that allows you to switch between the high and low end for FAM generally (between the 76% and 88% quoted from PP) with another option for "Perfectly" at 98%.
@B-u-g-e What do you think about this approach?
Three options is fine. I would probably go with 99% for the top, but I'm not wholly against 98% due to the uncertainty among the sources.