To design a patient self-rating wrist scale suitable for Chinese patients, and evaluate its reliability and validity.

The primary entry pool was established by referring to the existing foreign scales and the opinions of domestic experts. Opinions of 11 hand surgeons and 10 patients with wrist diseases were referred to select better items into the primary scale. During September 2015 to November 2016, 100 inpatients with wrist diseases in the hand surgery department of Beijing Jishuitan Hospital were selected by convenient sampling method, and the primary scale was conducted on them. Eight indices including item response rate, item differentiation, item-dimension attribution, variability, responsiveness, overall item attribution, internal consistency and factor loading were summarized. All the 8 indices were evaluated to establish the wrist patient self-evaluation instrument for Chinese. Test-retest reliability, Cronbach coefficient, expert score, KMO value, explanatory power, χ²/df, root mean square error of approximation (RMSEA) and comparative fit index (CFI) were used to evaluate the reliability and validity of the scale.

A total of 40 subjective items in the primary entry pool were selected to form the primary scale, including 32 items (A1-D4), and 4 dimensions (physiology, safety, pain and emotion). There were 92 valid scale results in 100 cases. All cases' response rate were over 90%. In terms of item differentiation, only the high grouping score [3.20±0.577 points (range, 1-3 points)] and the low grouping score [2.68±0.627 points (range, 2-5 points)] of item B10 had no statistical significance (t=5.11, P=0.340). There were 17 items: A1, A2, A5, A6, A7, A8, A9, A10, A11, A12, B4, B6, B7, C5, D1, D2, and D3 were considered to be deleted according to the result of item-dimension attribution. A total of 11 items had a variation less than 0.65: A4 (0.645), A7 (0.593), B1 (0.590), B5 (0.617), B8 (0.578), B9 (0.612), B10 (0.526), D1 (0.644), D2 (0.320), D3 (0.169), D4 (0.526). A2, A4, A6, A8, B4, B6, D1, D2, D3, C2, C3, C4, C5, C6 did not meet the reactivity requirements. Items with factor loads less than 0.4: D2 (-0.051), D3 (-0.127), and D4 (0.267). C4 (0.026), C5 (0.023), D1 (0.103), D2 (0.434), D3 (0.387), D4 (0.062) did not meet the internal consistency requirements. In multiple linear regression analysis, 19 items were not included in the final regression equation. Based on the above analysis, D1, D2, and D3 were finally deleted and the rest 29 valid items were remained to form the wrist patient self-evaluation instrument for Chinese. Reliability and validity of the scale: the test-retest reliability of physiology, safety, pain, emotion dimensions were 0.984, 0.976, 0.985 and 0.802 (P<0.001), respectively. Except for there was only one item in emotion dimension, the Cronbach coefficients of total score, physiology, safety and pain dimensions were 0.943, 0.973, 0.944 and 0.881, respectively. KMO was 0.894 (P<0.001). Except for there was only one item in emotion dimension, whose validity could not be evaluated. The χ²/df, CFI, RMSEA results were as follows, physiology: 5.152, 0.817, 0.022, respectively; safety: 5.378, 0.795, respectively; pain: 7.439, 0.865, 0.028, respectively.

The wrist patient self-evaluation instrument for Chinese is consisted of 4 dimensions and 29 items. As a subjective wrist self-rating scale suitable for modern Chinese patients, the scale has good reliability and validity, and can be one of the choices of the subjective evaluation for Chinese patients with wrist diseases.

Carpal joints; Reproducibility of results; Diagnostic self evaluation