For years, Parkinson’s trials have depended on ordinal scoring through the Unified Parkinson’s Disease Rating Scale — meaning symptoms are ranked in categories, not measured in exact units. But categories can miss subtle change. A February 16 study in npj Digital Medicine showed that smartphone video combined with AI can extract continuous gait metrics — things like velocity and joint movement — and even distinguish on vs off medication states. That’s not a replacement for clinical exams. It’s a