sgalgaR: a package for determining SGA and LGA babies.

Babies born small for gestational age (SGA) or large for gestational age (LGA) have a higher risk of morbidity and mortality. Small is often defined as <= 10^th percentile given the baby's sex and gestational age, or <= 3^rd percentile given the baby's sex and gestational age. Similarly, LGA is often defined in terms of the 90^th.

Finding look-up tables is straightforward enough, but these are not particularly useful for processing millions of records. This trivial package gives a percentile classifications (weight for gestational age and sex) for a single infant (ga_class()) or a dataframe of millions of infants (ga_dataframe()).

The possible percentile classes are: "<= 03", "<= 05", "<= 10", "10-90", ">= 90", ">= 95", ">= 97"

When processing a dataframe, the entire dataframe is returned with an additional column (ga_class)

Installation

You can install the package directly from GitHub using the devtools package

install.packages("devtools") # assuming you have not already
devtools::install_github("dreidpath/SGA-LGA")

Note

The classifications are based on US data, using the tables published by Talge et al (2014)

Reference

Talge NM, Mudd LM, Sikorskii A, Basso O. United States birth weight reference corrected for implausible gestational age estimates. Pediatrics; 2014 May;133(5):844-53. doi: 10.1542/peds.2013-3285. https://www.ncbi.nlm.nih.gov/pubmed/24777216