Table 1 The inclusion criteria

Study design

RCTs

Participants

Adults (older than 18 years) with a clinically confirmed diagnosis of DPN

Interventions

Low-level laser therapy

Comparisons

Sham LLLT, no treatment, active conventional medical treatment

Outcomes

At least one of the following outcomes: NCV, clinical scores that assess neurological function and related symptoms, quality of life scales, pain assessment tools