CN-macroEMG does not provide additional support for diagnosing inflammatory myopathies

We read with interest the article by ElZamarany et al. on a case-control study of the use of concentric needle macroelectromyography (CN-macroEMG) in 26 patients with Inflammatory Myopathies (IM) and 20 healthy control subjects.1 The study concludes that CN macroEMG provides optimal results in the diagnosis of IM and can be helpful in the follow-up of IM patients.1 The study is impressive, but some points should be discussed. The first point is that the objectives of the study were not specified.1 We should know whether the study was conducted to calculate the sensitivity and specificity of the method for diagnosing IM, or simply to document that CN-macroEMG may be abnormal in patients with IM. If the aim was to calculate sensitivity/specificity, we should know which gold standard for the diagnosis of IM was used to compare it with the CN-macroEMG findings. [...].