Table 1.
Characteristics of Included Studies for CTX-II.
| First Author | Year | Group | n | Females (n) | Age (Years) | BMI (kg/m2) | Diagnostic Criteria | Region | ELISA |
|---|---|---|---|---|---|---|---|---|---|
| Christgau13 | 2004 | Control | 415 | 444 | 61.4 ± 7.6 | NA | Healthy control | Belgium | CartiLaps ELISA assay |
| Knee OA | 212 | 66 | NA | ACR criteria | |||||
| Dam7 | 2009 | Control | 145 | 138 | 48 ± 16.52 | 24.9 ± 4.06 | Healthy control | Denmark | CartiLaps ELISA assay (Nordic Bioscience Diagnostics, Herlev, Denmark) |
| Knee OA | 142 | 64 ± 10.44 | 27.65 ± 4.1 | KL grade | |||||
| Garnero6 | 2001 | Control | 67 | 79 | 62.6 ± 8.1 | NA | Healthy control | France | CartiLaps ELISA assay (Osteometer Biotech, Herlev, Denmark) |
| Knee OA | 67 | 63.6 ± 9.1 | NA | ACR criteria | |||||
| Jordan8 | 2005 | Control | 97 | 0 | 64.5 ± 2.6 | 27.1 ± 1.2 | Healthy control | UK | CartiLaps ELISA assay |
| Knee OA | 79 | 0 | 65.05 ± 2.6 | 27.75 ± 1.1 | KL grade | ||||
| Jung14 | 2004 | Control | 48 | 29 | 64.67 ± 12.77 | NA | Gymnastics groups for elderly persons | Denmark | CartiLaps ELISA assay |
| Knee OA | 37 | 24 | 67.7 ± 8.2 | NA | Radiological and clinical manifestation of knee OA | ||||
| Kalai15 | 2012 | Control | 57 | 57 | 53.51 ± 8.54 | 30.73 ± 7.9 | Healthy control | Tunisia | CartiLaps ELISA assay (Nordic Bioscience Diagnostics, Herlev, Denmark) |
| Knee OA | 125 | 125 | 53.6 ± 7.6 | 32.79 ± 5.61 | ACR criteria | ||||
| Meulenbelt16 | 2006 | Control | 183 | 252 | 60.3 ± 7.5 | 27.0 ± 4.7 | Healthy control | Netherlands | CartiLaps ELISA assay (Nordic Bioscience Diagnostics, Herlev, Denmark) |
| Knee OA | 118 | 60.3 ± 7.5 | 27.0 ± 4.7 | ACR criteria + KL grade | |||||
| Ok17 | 2017 | Control | 36 | 15 | 29.6 ± 8.16 | NA | Healthy control | South Korea | Ann Arbor, MI, USA (IDS Nordic Bioscience, Herlev, Denmark) |
| Knee OA | 31 | 23 | 26.65 ± 4.13 | NA | Research Diagnostic Criteria for Temporomandibular Disorders | ||||
| Røtterud18 | 2014 | Control | 6 | 1 | 35.7 ± 2.3 | NA | Healthy control | Norway | CartiLaps ELISA assay (Nordic Bioscience Diagnostics, Herlev, Denmark) |
| Knee OA | 48 | 12 | 33.4 ± 9.0 | 27.3 ± 4.9 | International Cartilage Repair Society grade 3/4 | ||||
| Sowers19 | 2009 | Control | 36 | 36 | 47.5 ± 2.6 | 29.7 ± 6.2 | Healthy control | France | CartiLaps ELISA assay (Nordic Bioscience Diagnostics, Herlev, Denmark) |
| Knee OA | 36 | 36 | 47.5 ± 2.6 | 39.15 ± 8.22 | KL grade | ||||
| Tanishi9 | 2009 | Control | 106 | 59 | 60 ± 14.7 | NA | Healthy control | Japan | CartiLaps ELISA assay (Nordic Bioscience Diagnostics, Herlev, Denmark) |
| Knee OA | 190 | 112 | 72.07 ± 8.11 | NA | KL grade | ||||
| Xin11 | 2017 | Control | 20 | 12 | 57.6 ± 6.1 | NA | Healthy control | China | In house |
| Knee OA | 82 | 44 | 59.1 ± 6 | NA | KL grade | ||||
| Xu12 | 2010 | Control | 120 | 120 | 63.0 ± 12.8 | 25.6 ± 2.8 | Healthy control | China | ELISA assay (Shanghai Xitang Bio-Tech Company, China) |
| Knee OA | 120 | 120 | 65.3 ± 10.2 | 26.3 ± 3.1 | ACR criteria |
OA = osteoarthritis; CTX-II = C-terminal cross-linking telopeptide of type II collagen; ELISA = enzyme-linked immunosorbent assay; ACR = American College of Rheumatology; KL = Kellgren-Lawrence grade; BMI = body mass index; NA = not available.