Fig. 1From: Early recognition of multiple sclerosis using natural language processing of the electronic health recordTiming of clinical notes used in classification studies. For MS patients in the MS-enriched set, the notes used were written either before or after the entry of first ICD9 code for MS (IDC9[MS]). For control patients in the MS-enriched set and the Random sample set, the notes used were those entered within the last two years of the most recent noteBack to article page