Table 5. Mean ± SD for the temporal summation variables measured by cluster assignment in our osteoarthritis participants (n = 194).
| Cluster 1 (n = 54) |
Cluster 2 (n = 45) |
Cluster 3 (n = 63) |
Cluster 4 (n = 32) |
Adjusted P* |
|
|---|---|---|---|---|---|
| Forearm mechanical pain max | 13.1 ± 19.3† | 23.5 ± 25.1 | 30.7 ± 28.1 | 38.4 ± 30.9 | 0.008‡ |
| Forearm mechanical pain change | 7.9 ± 13.2§ | 14.7 ± 19.2 | 19.7 ± 18.9 | 22.8 ± 20.2 | 0.044‡ |
| Knee mechanical pain max | 19.8 ± 22.3† | 34.7 ± 29.1 | 39.8 ± 29.7 | 54.5 ± 31.2 | 0.001‡ |
| Knee mechanical pain change | 12.1 ± 14.5† | 22.7 ± 22.5 | 23.9 ± 18.9 | 29.3 ± 17.9 | 0.002‡ |
| Forearm 44°C heat pain max | 30.7 ± 25.9§ | 40.8 ± 30.7 | 46.1 ± 25.2 | 48.1 ± 26.7 | 0.117 |
| Forearm 44°C heat pain change | 3.4 ± 7.9§ | 6.8 ± 9.9 | 9.4 ± 15.1 | 9.6 ± 13.7 | 0.283 |
| Knee 44°C heat pain max | 21.9 ± 19.9‡ | 30.8 ± 28.7 | 37.6 ± 26.3 | 45.3 ± 24.1 | 0.016‡ |
| Knee 44°C heat pain change | 2.6 ± 6.2§ | 3.4 ± 6.3 | 8.3 ± 14.1 | 9.6 ± 14.5 | 0.050‡ |
| Forearm 46°C heat pain max | 35.6 ± 26.2‡ | 43.6 ± 29.3 | 53.3 ± 28.4 | 55.6 ± 28.0 | 0.033‡ |
| Forearm 46°C heat pain change | 3.8 ± 6.2‡ | 6.3 ± 8.4 | 11.4 ± 15.2 | 15.7 ± 19.7 | 0.018‡ |
| Knee 46°C heat pain max | 32.8 ± 26.6‡ | 43.9 ± 31.1 | 55.6 ± 30.4 | 59.0 ± 27.5 | 0.009‡ |
| Knee 46°C heat pain change | 7.8 ± 13.2§ | 6.7 ± 11.6 | 12.5 ± 18.6 | 16.3 ± 18.1 | 0.049‡ |
| Forearm 48°C heat pain max | 45.7 ± 28.0§ | 56.0 ± 32.8 | 64.8 ± 28.6 | 74.8 ± 25.6 | 0.021‡ |
| Forearm 48°C heat pain change | 8.4 ± 9.9† | 10.7 ± 12.1 | 14.2 ± 17.3 | 23.3 ± 21.6 | 0.009‡ |
| Knee 48°C heat pain max | 44.1 ± 30.4† | 51.9 ± 31.9 | 64.5 ± 29.9 | 72.0 ± 26.4 | 0.009‡ |
| Knee 48°C heat pain change | 11.2 ± 13.9§ | 9.8 ± 12.5 | 15.5 ± 18.1 | 21.8 ± 22.1 | 0.042‡ |
*
Controlling for race (0 = non-Hispanic white, 1 = African American), age, education (1 = high school, 2-year college degree, 4-year college degree, graduate degree), and testing site (0 = University of Florida, 1 = University of Alabama at Birmingham) as covariates.
†
Significant group differences between cluster 1 and cluster 4 and between cluster 1 and cluster 3 (P < 0.01 with Bonferroni adjustment).
‡
Significant.
§
Significant group differences between cluster 1 and cluster 4 (P < 0.01 with Bonferroni adjustment).