The full scholarly paper providing 'the 2014 self-consistent set of values of the constants and conversion factors of physics and chemistry recommended by the Committee on Data for Science and Technology (CODATA)' was published in September 2016 in Reviews of Modern Physics https://doi.org/10.1103/RevModPhys.88.035009
and is also openly available from the NIST website <http://ws680.nist.gov/publication/get_pdf.cfm?pub_id=920687
>. 'These values are based on a least-squares adjustment that takes into account all data available up to 31 December 2014.' The paper also provide ‘details of the data selection and methodology of the adjustment’.