To evaluate the inter-rater reliability of the mUPDRS-III in Mexican PD patients evaluated during the COVID19 pandemic through telemedicine.

A modified version of the MDS-UPDRS part III for virtual administration has been previously validated, and has been proposed as a useful alternative to face-to-face follow-up of patients with PD. Limitations of it’s use include the lack of evaluation of rigidity and postural impairment and technological barriers such as low-speed connection and poor access to web-yielding devices in remote areas (e.g.rural Mexico).

46 PD patients (mean age 65.34 ± 11.87 years, 58.7% male) were evaluated through web-based consultation (Cisco Webex). A brief follow-up questionnaire of symptoms, medications and current status was performed. Motor evaluation with the mUPDRS-III scale was applied independently by three movement disorders specialists. 

Agreement and reliability were evaluated using inter-rater correlation coefficient (ICC) and Kendall’s concordance coefficient accordingly. 

Total mUPDRS-III score (ICC 0.96, 95%CI 0.94-0.97; Kendall’s W 0.038, p<0.005) and four motor domain sub-scores -Language and Facial Expression (ICC 0.85, 95%CI 0.76-0.91; Kendall’s W 0.18, p<0.005), Bradykinesia (ICC 0.93, 95%CI 0.88-0.96; Kendall’s W 0.25, p 0.005), Tremor (ICC 0.86, 95%CI 0.78-0.92; Kendall’s W 0.233, p<0.005), Gait and Posture (ICC 0.97, 95%CI 0.95-0.98; Kendall’s W 0.018, p 0.434)- showed good to excellent agreement but slight to poor concordance.

We observed good agreement for motor domain sub-scores, as well as for the total scale score. This might confirm that the mUPDRS-III, albeit its intrinsic limitations, is a reproducible tool for the clinical follow-up of patients when face-to-face visits are not available. Nonetheless, the concordance values were poor which could be attributed to differences in rater perception of individual items due to technological barriers and to the sample’s homogeneity. Further analysis and test-retest might be useful to elucidate this phenomenon.