Table 4.
Demographic characteristics of the five clusters
| Low Pressure Pain Sensitivity (n=39) |
Average Pain Sensitivity (n=88) |
High TS of Punctate Pain (n=38) |
High Cold Pain Sensitivity (n=80) |
High Heat Pain & TS of Heat Pain (n=41) |
P | |
|---|---|---|---|---|---|---|
| Age, mean ± SD years | 55.8 ± 7.1 | 57.1 ± 8.0 | 55.2 ± 7.0 | 57.7 ± 7.9 | 56.1 ± 6.6 | 0.427 |
| BMI, mean ± SD kg/m2,a | 29.8 ± 5.6 | 29.7 ± 6.3 | 34.2 ± 9.3 | 32.2 ± 8.2 | 32.8 ± 7.0 | 0.005 |
| KL Score of Index Knee(%), χ2 | 0.586 | |||||
| KL score of 0 | 15 (41.67) | 36 (45.57) | 12 (34.29) | 42 (58.33) | 16 (45.71) | |
| KL score of 1 | 8 (22.22) | 12 (15.19) | 6 (17.14) | 9 (12.50) | 4 (11.43) | |
| KL score of 2 | 2 (5.56) | 13 (16.46) | 5 (14.29) | 5 (6.94) | 6 (17.14) | |
| KL score of 3 | 7 (19.44) | 13 (16.46) | 9 (25.71) | 9 (12.50) | 5 (14.29) | |
| KL score of 4 | 4 (11.11) | 5 (6.33) | 3 (8.57) | 7 (9.72) | 4 (11.43) | |
| Race, no. (%), χ2 | ||||||
| African Americans | 12 (32.4) | 39 (44.3) | 31 (81.6) | 45 (57.0) | 34 (85.0) | <0.0001 |
| Non-Hispanic Whites | 25 (67.6) | 49 (55.7) | 7 (18.4) | 34 (43.0) | 6 (15.0) | |
| Sex, no. (%), χ2 | ||||||
| Female | 12 (31.6) | 48 (55.2) | 27 (71.1) | 64 (80.0) | 31 (75.6) | <0.0001 |
| Male | 26 (68.4) | 39 (44.8) | 11 (28.9) | 16 (20.0) | 10 (24.4) | |
| Annual income, no. (%), χ2 | ||||||
| < $20,000 | 7 (18.9) | 30 (34.9) | 15 (40.5) | 26 (32.5) | 21 (52.5) | 0.009 |
| $20,000–29,999 | 7 (18.9) | 18 (20.9) | 5 (13.5) | 13 (16.3) | 6 (15.0) | |
| $30,000–49,999 | 6 (16.2) | 10 (11.6) | 10 (27.0) | 18 (22.5) | 9 (22.5) | |
| > $49,999 | 17 (46.0) | 28 (32.6) | 7 (18.9) | 23 (28.7) | 4 (10.0) | |
| Education, no (%), χ2 | 0.011 | |||||
| High school | 14 (36.8) | 36 (40.9) | 21 (55.3) | 34 (42.5) | 29 (70.7) | |
| 2-year college degree | 9 (23.7) | 24 (27.3) | 5 (13.2) | 20 (25.0) | 5 (12.2) | |
| 4-year college degree | 7 (18.4) | 16 (18.2) | 9 (23.7) | 12 (15.0) | 7 (17.1) | |
| Graduate degree | 8 (21.1) | 12 (13.6) | 3 (7.9) | 14 (17.5) | 0 | |
| Test, site no. (%), χ2 | 0.001 | |||||
| University of Florida | 30 (81.1) | 60 (72.3) | 17 (46.0) | 52 (70.3) | 24 (61.5) | |
| University of Alabama at Birmingham | 7 (18.9) | 23 (27.7) | 20 (54.0) | 22 (29.7) | 15 (38.5) |
a
Significant group differences between the High TS of Punctate Pain Cluster and all other Clusters (p<0.05, Bonferroni)