Table. Summary of Patient-Reported Outcomes at 24 Months.
| Patient-reported outcomea | No. (%) | |
|---|---|---|
| Closed-loop group (n = 50) | Open-loop group (n = 42) | |
| Oswestry Disability Index | ||
| Change from baseline, mean (SD) | 26.0 (13.6)b | 23.2 (14.5)b |
| % Change from baseline, mean (SD) | 47.8 (24.6)b | 42.2 (27.4)b |
| Minimum clinically important difference (score ≥15) | 41 (82.0) | 30 (71.4) |
| Minimal or moderate disability (score, 0-40)c | 39 (78.0) | 25 (59.5) |
| Profile of mood states total mood disturbance | ||
| Change from baseline, mean (SD) | 18.6 (19.4)b,d | 9.4 (15.1)b |
| Minimum clinically important difference (score ≥10) | 34 (68.0)d | 18 (42.9) |
| Short Form Health Survey Physical Component Summary | ||
| Change from baseline, mean (SD) | 10.1 (11.0)b | 11.0 (10.0)b |
| Minimum clinically important difference (score ≥6) | 33 (66.0) | 26 (63.4) |
| Short Form Health Survey Mental Component Summary | ||
| Change from baseline, mean (SD) | 6.7 (11.6)b,d | −1.4 (10.0) |
| Minimum Clinically Important Difference (score ≥7) | 23 (46.0)d | 9 (22.0) |
| EQ-5D-5L Index score | ||
| Change from baseline, mean (SD) | 0.254 (0.157)b | 0.208 (0.163)b |
| Minimum clinically important difference (score ≥0.074) | 43 (86.0) | 35 (83.3) |
| EuroQol-visual analog scale | ||
| Change from baseline, mean (SD) | 26.9 (19.9)b | 19.5 (21.7)b |
| Pittsburgh Sleep Quality Index | ||
| Change from baseline, mean (SD) | 4.1 (4.3)b | 4.1 (4.7)b |
| Minimum Clinically Important Difference (score ≥3) | 31 (63.3) | 26 (61.9) |
| Patient Global Impression of Change | ||
| Very much improved or much improved | 42 (84.0) | 34 (81.0) |
Positive change indicates improvement. Patient-reported outcomes collected included health-related quality of life measured by the Short Form Health Survey,16 which has a minimum clinically important difference (MCID) of 6 points for the Physical Component Summary and 7 points for the Mental Component Summary,16 and the European Quality of Life Five-Dimensional Five-Level (EQ-5D-5L),17 which has an MCID of 0.07418 for the index score; functional disability measured by the Oswestry Disability Index,19 which has an MCID of 15 points20; emotional functioning measured by the Profile of Mood States,21 which has an MCID of 10 points for Total Mood Disturbance22; sleep quality measured by the Pittsburgh Sleep Quality Index,23 which has an MCID of 3 points24; and Patient Global Impression of Change, which measures the impact of therapy on health status and tends to reflect other aspects such as treatment convenience, cost, and adverse reaction burden.
Significant within-group improvement from baseline (P < .05).
No patients had minimal or moderate severity on the Oswestry Disability Index (score, 0-40) at baseline. For study inclusion, patients were required to be classified as having a severe disability or “crippled” on the Oswestry Disability Index (score, 41-80).
Significant difference between treatment groups (P < .05).