Table 5.
Effect of WJD on thin-side CTR, thick-side CTR, and CTRR: post-hoc analysis of ANCOVA.
| Thinner side CTR, Analysis 3 | ||||||
| Thick-side WJD (−) | Thick-side WJD (+) | EM mean | Main effect | p-value | ||
| Thin-side WJD (−) | 0.443 | 0.383 | 0.413 | −0.056 | 0.005 ** | |
| Thin-side WJD (+) | 0.387 | 0.326 | 0.356 | |||
| EM mean | 0.415 | 0.354 | ||||
| Main effect | −0.060 | |||||
| p-value | 0.004 ** | |||||
| Thicker side CTR, Analysis 3 | ||||||
| Thick-side WJD (−) | Thick-side WJD (+) | EM mean | Main effect | p-value | ||
| Thin-side WJD (−) | 0.482 | 0.390 | 0.436 | −0.010 | 0.63 | |
| Thin-side WJD (+) | 0.473 | 0.380 | 0.426 | |||
| EM mean | 0.477 | 0.385 | ||||
| Main effect | −0.093 | |||||
| p-value | <0.001 ** | |||||
| Logit CTRR, Analysis 2 | ||||||
| Thick-side WJD (−) | Thick-side WJD (+) | Simple main effect | OR | p-value | ||
| Thin-side WJD (−) | 2.883 a | 2.642 b | b-a | −0.242 | 0.785 | 0.57 |
| Thin-side WJD(+) | 1.423 c | 2.255 d | d-c | 0.833 | 2.300 | 0.014 * |
| c-a | d-b | |||||
| Simple main effect | −1.461 | −0.386 | ||||
| OR | 0.232 | 0.680 | ||||
| p-value | <0.001 ** | 0.38 | ||||
In each patient, the side with the lower cortical thickness rate (CTR) of the metacarpals was designated the “thin-side” and that with the higher CTR the “thick-side”. WJD: wrist joint damage. CTRR: cortical thickness rate ratio = CTR (thin-side)/CTR (thick-side). Logit CTRR = ln {CTRR/(1-CTRR)}. To ensure normality of variables for the analysis of covariance (ANCOVA), the variable CTRR was transformed using a logit transformation. This process involved applying the logit function to CTRR values, defined as: Logit CTRR = ln {CTRR/(1-CTRR)}. Analysis 1: ANCOVA with the following dependent variable and factors: age, sex (female), dominant hand, WJD thin-side, WJD thick-side, and interaction between thin- and thick-side WJDs. Analysis 2: ANCOVA with the following dependent variable and factors: age, WJD thin-side, WJD thick-side, and interaction between thin- and thick-side WJDs. (excluding sex (female) and dominant hand in Analysis 1). Analysis 3: ANCOVA with the following dependent variable and factors: age, WJD thin-side, WJD thick-side (excluding interaction between thin- and thick-side WJDs in Analysis 2). EM = estimated marginal mean, the adjusted mean accounting for covariates in the ANCOVA model. OD: odds ratio. *: significant, p-value < 0.05. **: significant, p-value < 0.01.