Stevic 2001.

Methods	Randomised, double‐blind, placebo‐controlled trial with parallel group design (two intervention groups).
Participants	Country: Yugoslavia. Number of participants randomised: 28, 75% men and 25% women, aged 20 to 70 years, mean age 57 years. Inclusion criteria: probable or definite ALS by El Escorial criteria, age 20 to 70 years, disease duration < 3 years, ambulatory. Exclusion criteria: significant compromise of bulbar or respiratory function, conduction block, M protein, significant imaging abnormality, dementia, and concurrent systemic disease.
Interventions	Participants were randomly assigned to receive: group 1: alsemet‐L‐methionine (2 g), vitamin E (400 IU), selenium (3 x 10‐5g) three times daily (n = 16); group 2: placebo (n = 12); for a period of one year.
Outcomes	The primary outcome measures were: survival and rate of disease progression as expressed by decline in limb‐function, bulbar‐function and muscle‐testing scores. Secondary outcome measures were: activity of antioxidative components, and level of vitamin E in blood.
Notes	Compliance with treatment is not reported. There were no losses to follow‐up.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	The trial is described as randomised, but the method of sequence generation was not specified.
Allocation concealment (selection bias)	Unclear risk	The trial was described as randomised but the method used to conceal the allocation was not described, so that intervention allocations may have been foreseen in advance of, or during, enrolment.
Blinding (performance bias and detection bias) All outcomes	Low risk	The trial was described as blinded, the parties that were blinded, and the method of blinding was described, so that knowledge of allocation was adequately prevented during the trial.
Incomplete outcome data (attrition bias) All outcomes	High risk	The number or reasons for dropouts and withdrawals were not described.
Selective reporting (reporting bias)	Low risk	Pre‐defined, or clinically relevant and reasonably expected outcomes are reported on.
Other bias	Unclear risk	The trial may or may not be free of other components that could put it at risk of bias.