Twitch mouth pressure for detecting respiratory muscle weakness in suspicion of neuromuscular disorder

•Maximal inspiratory pressure measurement is noninvasive but requires cooperative patients.•Twitch transdiaphragmatic pressure measurement requires the insertion of an esophageal catheter.•Twitch mouth pressure measurement is nonvolitional/noninvasive and provides reliable results.•Combining volitional and nonvolitional noninvasive tests constitutes an optimal strategy for assessing respiratory muscle function.