Reply to Comment on Environmental and Occupational Risk Factors of Amyotrophic Lateral Sclerosis: A Population-Based Case-Control Study

摘要

We much appreciate the positive comments and interest concerning our study on the environmental and occupational risk factors of amyotrophic lateral sclerosis (ALS) [1]. As correctly noted by these authors, in our paper we already acknowledged some limitations they outline. They included recall bias, since exposure assessment relied on self-reporting using a questionnaire, as well as the small sample size influencing the low number of exposed subjects in such categories, including the subjects working in the agricultural sector, decreasing as a consequence the statistical precision of the estimate [2].