Pinto 1995.

Methods	Single‐centre, open, parallel‐group study with a 3‐year follow‐up period
Participants	20 participants having ALS with bulbar features (definite diagnostic criteria) and with chronic hypercapnic respiratory failure
Interventions	Control: oxygen, bronchodilators and other palliative measures Experimental group: non‐invasive nasal nocturnal ventilation with bilevel airway pressure
Outcomes	Mortality at 1 and 3 years Survival time Bulbar and spinal Norris scores Quality of life Modified Barthel score Arterial blood gases Respiratory function tests
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Participants were alternately assigned to experimental or control arms
Allocation concealment (selection bias)	High risk	Participants were alternately assigned to experimental or control arms
Blinding of participants and personnel (performance bias) All outcomes	High risk	No party was blinded to the intervention
Blinding of outcome assessment (detection bias) All outcomes	High risk	The outcome assessor was not blinded to the intervention
Incomplete outcome data (attrition bias) All outcomes	Low risk	No loss to follow‐up
Selective reporting (reporting bias)	Low risk	Outcomes presented in the results section matched those reported in the methods