PT - JOURNAL ARTICLE AU - O’Neill, Thomas R. AU - Peabody, Michael R. AU - Puffer, James C. TI - THE ABFM BEGINS TO USE DIFFERENTIAL ITEM FUNCTIONING AID - 10.1370/afm.1587 DP - 2013 Nov 01 TA - The Annals of Family Medicine PG - 578--579 VI - 11 IP - 6 4099 - http://www.annfammed.org/content/11/6/578.short 4100 - http://www.annfammed.org/content/11/6/578.full SO - Ann Fam Med2013 Nov 01; 11