To characterize data quality and to qualitatively describe perceived causes and risk factors for ALS among a cohort of survey respondents.

ALS is a progressively fatal neurodegenerative disorder with poorly understood etiology that typically results in death within 2–5 years. A goal of ATSDR’s congressionally-mandated National ALS Registry is to examine risk factors associated with ALS. Risk factor data are collected using a validated, voluntary web-based survey completed by respondents that self-register in the Registry. The survey includes a two-question, free-text module for respondents to detail perceptions of causes and risks for their ALS and for ALS in general.

The majority of respondents were aged 50-79 (78.9%), male (60.0%), and white (91.9%). More respondents provided line listings and/or substantive answers to the “what caused your ALS” question (67.5%) compared with the “what caused ALS in general” question (36.2%). ‘I Don’t Know’ and blank responses represented 32.5% and 63.8% of responses for the two questions, respectively. Thematic responses were similar across both questions and included genetics/familial history, military experience, environmental exposures, occupational/chemical exposures, nutritional intake, physical activity, physical trauma/concussions, stress, the interplay of multiple risk factors, and other factors.