Data-Driven PD Subtype Calculator — Disease-Duration Percentiles

Patient inputs

Years since PD diagnosis (integer 1–5; round down) MDS-UPDRS Part II total (0–52, patient-reported motor ADL)

052

MDS-UPDRS Part III off-medication total (0–132; or untreated visit)

0132

PIGD / TD ratio (Stebbins 2013; winsorized at 4.40)

04.4

RBDSQ-13 total (0–13; 13-item REM Sleep Behavior Disorder Screening Questionnaire)

013

SCOPA-AUT total (0–69; Scales for Outcomes in PD – Autonomic)

069

MoCA total (0–30; Montreal Cognitive Assessment, lower = worse)

030

Assigned subtype

Subtype

—

Enter all values to compute

Motor composite (mean of 3 z-scores) —

Year-specific 75th-percentile threshold —

Above threshold (worst-motor)? —

Channel-by-channel breakdown

Fereshtehnejad 2017 assignment rule (year-specific)

DM-PD = worst-motor AND ≥ 1 non-motor worst, OR all 3 non-motor worst

MMP-PD = motor composite and all 3 non-motor scores below their thresholds (MoCA above)

IM-PD = everything else, including any score exactly at its threshold (unless DM-PD)

Percentile thresholds derived from PPMI April-2026 freeze (N=1,030 de novo idiopathic PD).
Use restricted to research and clinical-decision support; not a diagnostic device.
Cite: Negida A, Mukhopadhyay N, Berman BD, Fereshtehnejad SM, Barrett MJ. Disease-Duration–Specific Percentiles for Prospective Subtyping of Parkinson's Disease: A PPMI-Based Study. Mov Disord Clin Pract. 2026. doi:10.1002/mdc3.70740 Source code & data: github.com/Negidamd/data-driven-pd-subtype-calculator | Method: Fereshtehnejad et al., Brain 2017 | Cutoff data: see T_reference_percentiles.csv