v4.1.0

CDC (Centers for Disease Control and Prevention)

Version 4.1 is the first version to include the CDC charts. CDC is made up of WHO (0-2y) and CDC (2y+). The WHO version used by CDC though has been tweaked, presumably to make the disjunction between the references less marked. The effect is that the code base now has 2 versions of WHO - the WHO one and the US interpretation. CDC BMI is included; for BMI measurements > 95th centile some clever maths is introduced to prevent some of the issues that have been detailed in conversations about the accuracy of z scores.

Note that there is no preterm data for the moment. The Canadian Fenton data is what is typically used, but this is licensed and conversations about the legals are ongoing. This means that for all corrected ages < 0 no values are returned, but a meaningful error is included.

There is also a fix to the confusing error raised when Estimated Date of Delivery (EDD) has not yet been reached in a preterm baby.

There are also tests for the same test subjects used in UK-WHO, but recalculated for CDC using the excellent R package [cdcanthro] (https://github.com/CDC-DNPAO/CDCAnthro) by David Freedman, author of the CDC BMI reference.