Repeatability of assessment
Consistency of re-examination affects clinical outcome and management decisions. When the 5-point scale is used, it is clear that the intra-rater consistency is lower, compared to the 3 point score.
The diagnosis of vocal cord paresis is felt to be more challenging than vocal cord paralysis12. This is highlighted in this study with the low inter rater specific agreement for the scores 1, 2 and 3 in the 5 point scale, and score 1 in the 3 point scale (Table 3), which demonstrates that clinicians disagree with what they are seeing when vocal cord paresis is present. Vocal cord movement is a continuum with paresis not as well recognised or studied as paralysis. Wu et al highlighted that in laryngology practice in North America, the most common diagnostic tool for diagnosing paresis was stroboscopy, not flexible nasendoscopy. Simpson et al reported that in a large series of 739 patients presenting to a tertiary laryngology service with a chief complaint of dysphonia, of the 26.4% with paresis or paralysis on stroboscopy, only 1.8% of the patients had LEMG confirmed vocal fold paresis. In stark comparison Satalof et al demonstrated that in his series of 689 patients with suspected paresis or paralysis, the LEMG confirmed this diagnosis in 95.9% of the patients. This significant variation between diagnosis and confirmation on LEMG highlights that we are still not able to consistently differentiate between these diagnoses. Although LEMG is the only way to confirm definitively that a patient has a paralysis or paresis, it is not routinely performed in clinical practice.