This is a retrospective cohort study to assess the factor associated with success of non-invasive positive ventilation in ALS patients.

Patients with ALS who were admitted to a tertiary hospital for initially applying non-invasive positive pressure ventilation (NIPPV). The objective of this study was to investigate factors associated with optimal NIPPV initiation and adherence, and to assess the long-term effects of NIPPV adherence in ALS patients.

Inclusion Criteria:

• Patients fulfilling the El Escorial World Federation criteria for probable, or definite ALS
• Aged ≥ 19 years
• Patients who performed blood gas analysis including venous blood gas and arterial blood gas before NIPPV application.

Exclusion Criteria:

• Patients who had experience in applying the NIPPV or currently using NIPPV
• Patients who applied in outpatient settings
• Patients who did not perform blood gas analysis before NIPPV application
• Patietns who had a history of asthma or COPD,
• Patients who didn't have any record of NIPPV application time

ALS patients who were admitted for applying non-invasive positive pressure ventilation initially.