Table 1.
Demographic, socio-economic and clinical characteristics of the study population at baseline and the follow-up visit
| Characteristic (n = 80) | Baseline | 3-month follow-up |
|---|---|---|
| Female, % | 58.8 | |
| Age, median (IQR), years | 57.3 (44.9–65.9) | |
| Education | ||
| Compulsory schooling not completed, % | 5.0 | |
| Compulsory schooling completed, % | 48.8 | |
| Secondary school level, % | 20.0 | |
| University or similar, % | 26.3 | |
| Prior smartphone use, % | 50.0 | |
| Native language | ||
| German, % | 85.0 | |
| Other, % | 15.0 | |
| Currently employed, % | 43.6 | |
| RA duration since diagnosis, median (IQR), years | 4.5 (1.1–9.5) | |
| RA symptom duration, median (IQR), years | 5.1 (1.6–12.2) | |
| DMARD use, % | 82.5 | 92.5 |
| Biologic DMARD use, % | 31.3 | 39.2 |
| DAS28 | ||
| Median (IQR) | 2.4 (1.9–3.5) | 2.4 (1.7–3.7) |
| ≤2.6 (remission), % | 55.8 | 54.8 |
| >2.6 to ≤ 3.2 (low disease activity), % | 15.6 | 12.3 |
| >3.2 to ≤ 5.1 (moderate disease activity), % | 26.0 | 26.0 |
| >5.1 (high disease activity), % | 2.6 | 6.9 |
| CDAI | ||
| Median (IQR) | 7.6 (4.3–16.5) | 5.7 (2.0–14.2) |
| ≤2.8 (remission), % | 16.9 | 33.3 |
| >2.8 to ≤ 10 (low disease activity), % | 44.1 | 35.9 |
| >10 to ≤ 22 (moderate disease activity), % | 27.3 | 15.4 |
| >22 (high disease activity), % | 11.7 | 15.4 |
| SDAI | ||
| Median (IQR) | 10.5 (6.6–20.4) | 8.6 (4.9–22.1) |
| ≤3.3 (remission), % | 10.7 | 11.0 |
| >3.3 to ≤ 11 (low disease activity), % | 44.0 | 47.9 |
| >11 to ≤ 26 (moderate disease activity), % | 28.0 | 23.3 |
| >26 (high disease activity), % | 17.3 | 17.8 |
| RAPID3 | ||
| Median (IQR) | 6.6 (3.1–11.9) | 6.4 (2.6–12.3) |
| ≤3 (near remission), % | 25.0 | 28.7 |
| 3.1 to ≤ 6 (low severity), % | 21.2 | 18.8 |
| 6.1 to ≤ 12 (moderate severity), % | 28.8 | 27.5 |
| >12.1 (high severity), % | 25.0 | 25.0 |
| RAPID4 | ||
| Median (IQR) | 7.8 (3.5–15.1) | 7.6 (3.0–15.8) |
| ≤4 (near remission), % | 30.0 | 32.5 |
| 4 to ≤ 8 (low severity), % | 20.0 | 18.8 |
| 8 to ≤ 16 (moderate severity), % | 30.0 | 23.8 |
| >16 (high severity), % | 20.0 | 25.0 |
| SF-36 PCS, median (IQR) | 43.8 (36.5–52.6) | 46.1 (38.6–53.2) |
| SF-36 MCS, median (IQR) | 50.7 (37.4–58.0) | 50.1 (35.6–58.9) |
| HAQ-DI, median (IQR) | 0.38 (0.13–1.13) | 0.38 (0.13–1.25) |
| FACIT-F, median (IQR) | 38 (15–47) | 38 (26–42) |
CDAI: Clinical Disease Activity Index; Education: compulsory schooling is defined as 9 years of schooling, and secondary school level includes vocational training; FACIT-F: Functional Assessment of Chronic Illness Therapy—Fatigue; HAQ-DI: HAQ Disability Index; IQR: interquartile range; RAPID: Routine Assessment of Patient Index Data; SDAI: Simplified Disease Activity Index; SF-36 MCS: Short Form-36 Mental Component Summary; SF-36 PCS: Short Form-36 Physical Component Summary.