Table 1. Baseline Characteristics of Participants by Group.
| Characteristic | Mean (SD) | Standardized difference, %a | |
|---|---|---|---|
| Intervention (n = 103) | Control (n = 103) | ||
| Age, y | 60.3 (8.2) | 59.0 (8.5) | 15.4 |
| Female, No. (%) | 60 (58) | 66 (64) | −12.0 |
| Height, m | 1.7 (0.1) | 1.7 (0.1) | 5.3 |
| Body mass, median (IQR), kg | 89.0 (76.0-105.0) | 90.0 (76.0-106.0) | 2.4 |
| BMI, median (IQR) | 31.1 (26.6-34.9) | 31.6 (26.9-36.4) | −0.2 |
| Geographic location,b No. (%) | |||
| Metropolitan | 64 (62) | 58 (56) | 11.9 |
| Regional | 39 (38) | 45 (44) | −11.9 |
| Education level | |||
| Secondary | 49 (48) | 48 (47) | 2.0 |
| Tertiary (university or equivalent) | 54 (52) | 55 (53) | −2.0 |
| Currently employed, No. (%) | 62 (60) | 70 (68) | −16.2 |
| Symptom duration, y | 8.5 (10.0) | 7.7 (8.0) | 8.1 |
| Laterality, No. (%) | |||
| Unilateral OA | 38 (37) | 42 (41) | −8.0 |
| Bilateral OA | 65 (63) | 61 (59) | 8.0 |
| Problems in other joints, No. (%) | |||
| Back | 35 (34) | 37 (36) | −4.1 |
| Hip | 27 (26) | 31 (30) | −8.6 |
| Shoulder | 26 (25) | 28 (27) | −4.4 |
| Hand | 26 (25) | 25 (24) | 2.3 |
| Neck | 23 (22) | 21 (20) | 4.7 |
| Foot | 21 (20) | 27 (26) | −13.8 |
| Treatments for knee OA in past 6 mo, No. (%) | |||
| ≥1 Treatment | 87 (84) | 96 (93) | −28.0 |
| Land-based exercises | 55 (53) | 49 (48) | 11.7 |
| Heat/cold treatment | 51 (50) | 66 (64) | −29.7 |
| Massage | 32 (31) | 42 (41) | −20.3 |
| Knee braces | 26 (25) | 39 (38) | −27.4 |
| Orthotics, arch supports | 23 (22) | 24 (23) | −2.3 |
| Manual therapy | 21 (20) | 22 (21) | −2.4 |
| Hydrotherapy | 20 (19) | 14 (14) | 15.7 |
| Walking stick | 16 (16) | 10 (10) | 17.6 |
| TENS | 13 (13) | 11 (11) | 6.1 |
| Injections (eg, cortisone, hylan G-F 20, platelet-rich plasma) | 9 (9) | 9 (9) | 0.0 |
| Therapeutic ultrasound | 8 (8) | 9 (9) | −3.5 |
| Acupuncture | 8 (8) | 8 (8) | 0.0 |
| Arthroscopic surgery | 4 (4) | 8 (8) | −16.6 |
| Low-level laser therapy | 0 | 2 (2) | −19.9 |
| High-tibial osteotomy surgery | 0 | 2 (2) | −19.9 |
| Ligament reconstruction | 0 | 3 (3) | −24.5 |
| Current pain medication use,c No. (%) | |||
| ≥1 Medication used | 86 (83) | 91 (88) | −14.0 |
| Analgesics (paracetamol combinations) | 66 (64) | 73 (71) | −14.6 |
| Topical anti-inflammatory drugs | 59 (57) | 69 (67) | −20.1 |
| Nonsteroidal anti-inflammatory drugs | 55 (53) | 63 (61) | −15.8 |
| Cyclooxygenase-2 inhibitors | 12 (12) | 16 (16) | −11.4 |
| Oral opioids | 5 (5) | 5 (5) | 0.0 |
| Oral corticosteroids | 1 (1.0) | 0 | 14.0 |
| Comorbid conditions, No. (%) | |||
| ≥1 Comorbid condition | 55 (53) | 57 (55) | −3.9 |
| High blood pressure | 36 (35) | 37 (36) | −2.0 |
| Depression | 14 (14) | 15 (15) | −2.8 |
| Diabetes | 10 (10) | 6 (6) | 14.6 |
| Spine condition, including arthritis | 9 (9) | 11 (11) | −6.6 |
| Lung disease | 7 (7) | 7 (7) | 0.0 |
| Other | 10 (10) | 9 (9) | 3.4 |
| Exercise importanced | 6.1 (1.2) | 6.1 (1.2) | 0.8 |
Abbreviations: BMI, body mass index calculated as weight in kilograms divided by height in meters squared; IQR, interquartile range; OA, osteoarthritis; TENS, transcutaneous electrical nerve stimulation.
a
Calculated as intervention minus control group.
b
Based on residential postal code, in accordance with Australian Statistical Geography Standard.
c
Defined as ≥1 per week during the prior 6 mo.
d
Rated by level of agreement with the statement “How important is it to you to do regular exercise to manage your knee condition?” Scores range from 1-7, with higher scores indicating higher agreement.