Table 2. Inclusion and exclusion criteria.

	Inclusion criteria	Exclusion criteria
Study design	Randomized clinical trials	Observational studies, qualitative studies, books, case reports, gray literature, review articles, conference proceedings
Intervention	Alpha-lipoic acid	Any other antioxidant intervention, other treatment approaches, combination treatment
Population	Type 1 diabetes, type 2 diabetes, diabetes mellitus, adults, peripheral neuropathy	Any non-diabetic population, pediatric populations