Table 2.
Predicting intervention outcomes using data collected pre-intervention and a k-nearest neighbor model
Machine learning: k-nearest neighbor model | ||||||
---|---|---|---|---|---|---|
Feature sets | All participants | Unexpected non-responder | ||||
Outcome prediction for | Outcome prediction for | |||||
ARAT | BBT | NHPT | ARAT | BBT | NHPT | |
Balanced accuracy (%) | Correct (yes/no) | |||||
1 | 55 | 63 | 43 | y | y | y |
2 | 49 | 28 | 54 | n | n | y |
3 | 52 | 37 | 43 | y | y | y |
4 | 43 | 53 | 40 | n | n | y |
5 | 77 | 66 | 71 | y | y | y |
6 | 80 | 63 | 64 | n | y | n |
1, 2 | 83 | 80 | 43 | y | y | y |
1, 3 | 60 | 25 | 50 | y | y | y |
1, 4 | 55 | 46 | 63 | y | y | y |
1, 5 | 69 | 55 | 64 | y | y | y |
1, 6 | 93 | 59 | 33 | n | y | n |
1, 2, 3 | 71 | 35 | 50 | y | y | y |
1, 4, 6 | 68 | 42 | 48 | n | y | n |
1, 5, 6 | 85 | 60 | 68 | n | y | y |
1, 4, 5, 6 | 64 | 69 | 61 | n | y | n |
1, 2, 3, 4, 5, 6 | 68 | 59 | 64 | n | y | y |
Multiple machine learning models were trained using different feature sets (independent variables, 1–6). The training label indicated whether a considerable change across intervention was observed in a specific conventional score (dependent variable; ARAT, BBT, or NHPT). The models were evaluated in a leave-one-out cross-validation and specifically tested for one individual with strong activity limitations who did not show improvements across neurorehabilitation (referred to as unexpected non-responder). Feature set nomenclature: (1) patient master data (ms type, chronicity, age, sex); (2) intervention group; (3) disability (EDSS, disability group); (4) conventional scales of body functions (motricity index, static fatigue index, monofilament index, symbol digit modality test, Fahn’s tremor rating scale); (5) digital health metrics of sensorimotor impairments (ten VPIT metrics); (6) Conv. scale of activity (ARAT, NHPT, BBT). The best performing (accuracy and unexpected non-responder) models relying on the least amount of features are highlighted in bold for each conventional scale. ARAT: Action Research Arm Test. BBT: Box and Block Test. NHPT: Nine Hole Peg Test. VPIT: Virtual Peg Insertion Test