Amyotrophic Lateral Sclerosis (ALS) is a fatal and currently incurable disease. Treatment is mostly palliative and focuses on improving the quality of life (QoL) of patients; knowledge of the determinants of QoL can have an impact on their care. The aim of this work is to identify which factors are related to QoL in ALS using two different metrics of a person's overall QoL from the McGill QoL questionnaire. We used an ensemble of feature selection methods in order to reduce bias. We found differences in the predictors of the two scores, but caregiving duties of informal caregivers were among the most significant ones in both cases. Our future work will be the development of a Clinical Decision Support System for the prediction of QoL in ALS patients using the most important features from this study.