Alignment of 5–2–1 criteria with Neurologists' clinical judgment in identifying Advanced Parkinson’s Disease in Morocco: A cross-sectional inter-rater agreement study

Accurate identification of advanced Parkinson’s disease (APD) is crucial for optimizing treatment strategies and ensuring timely consideration of device-aided therapies. The 5–2–1 criteria, derived from an expert consensus using a Delphi-panel approach, have been proposed as a simplified and practical tool for identifying APD. This study evaluates the agreement between Moroccan neurologists’ clinical judgment and the Delphi-panel clinical indicators, with particular focus on the 5–2–1 criteria. A cross-sectional study was conducted over 9 months across 15 private and public facilities in five cities in the Casablanca–Settat region. Neurologists independently determined APD status, which was compared with classifications based on the 5–2–1 criteria and the remaining Delphi-panel indicators. The 5–2–1 criteria were defined by the presence of at least one of the following: ≥5 daily doses of oral levodopa, ≥ 2 h of “off” time per day, or ≥ 1 h of troublesome dyskinesia. Agreement was evaluated with Cohen’s kappa (κ). A total of 370 patients with Parkinson’s disease were included (mean age 65.1 ± 10.7 years; 50.5% male). The 5–2–1 criteria classified 44.6% of patients (95% CI: 39.5%–49.8%) as having APD, while neurologists identified 43.2% (95% CI: 38.3%–48.3%). The two assessments aligned in 73% of cases, indicating moderate agreement (κ = 0.48; 95% CI: 0.43–0.53). The highest agreement was observed when at least two 5–2–1 criteria were met (κ = 0.73; 95% CI: 0.69–0.77), with 90.6% sensitivity and 83.8% specificity, outperforming the standard 5–2–1 classification in terms of specificity (55.2%). Among individual criteria, levodopa dosing ≥ 5 times daily showed the highest agreement (κ = 0.71; 95% CI: 0.67–0.75). The 5–2–1 criteria, particularly when refined to a two-criteria threshold, represent a reliable and practical approach for identifying APD and facilitating timely referral for advanced therapies in Morocco.