Discussion
The Chinese version of the PaArticular Scales is a patient-relevant outcome assessment tool and satisfies the objectivity, reliability, and validity of interval scale measurements. This study found that the Activity subscale had 3 factors (i.e., latent variables) and the Participation subscale had a single factor. The 3 factors in the Activity subscale were lower-limb activity, upper-limb activity, and self-care activity; and the 1 factor in the Participation subscale was participation. The 2 subscales explained 75.176% and 62.825% of the variance in the scale, respectively, indicating that the results had practical significance.
The Chinese version of the PaArticular Scales had excellent internal consistency and reliability. Cronbach’s α coefficients for the Activity subscale and Participation subscale were .97 and .94, respectively, which were slightly higher than those found by Müller et al. for 191 elderly residents with joint contractures in German LTC facilities (α = .96 and .92).12 Although the 2 studies were carried out in different countries, the αcoefficient values were found to be very close. According to the standard set by Nunnally and Bernstein (α coefficient ≥ .80),38 the PaArticular Scales have excellent internal consistency and reliability across ethnic groups.
The criterion validity tests showed that for individuals older than 64 years with severe joint contractures, strong evidence indicates that the Chinese version of the PaArticular Scales is linearly related to the WHODAS 2.0-36 items (r = .770, p < .001). The Pearson correlation coefficient is large. These results show that, similar to the WHODAS 2.0 ̵̵36 items, the PaArticular Scales developed using the ICF of the WHO as the standard can be another simple tool for the clinical measurement of activity and participation, and it addresses the gap for measuring patients with joint contractures.5 However, although the Chinese version of the PaArticular Scales is also based on the ICF, it is mainly used for patients with joint contractures, which is different from the widely used WHODAS 2.0 ̵̵36 items. Perhaps this difference can explain why the correlation between the 2 scales was not very high. Another reason may be that the majority of the participants in this study were institutionalized residents and required nursing care. Obviously, these characteristics are not considered to be associated with the applicable subjects of the WHODAS 2.0 ̵̵36 items; therefore, the result may be caused by many different composition characteristics (for example, physical conditions).
Criterion validity was also assessed to test the correlation between the Chinese version of the PaArticular Scales and the established Chinese version of the WHOQOL-BREF. For individuals older than 64 years with severe joint contractures, very strong evidence indicates that the Chinese version of the PaArticular Scales is linearly related to the WHOQOL-BREF (r = -.553, p < .001). The Pearson correlation coefficient is large. The newly developed scale demonstrated criterion validity, which was consistent with findings by Chen et al.10 The study noted that activity and participation, personal factors, and body function and structure are determinants of QOL for elderly residents in LTC facilities. Among them, activity and participation have the best explanatory power, up to 52.1%, indicating that activity and participation have practical significance for the QOL of elderly residents. The results also echo the view of Rantanen et al. that providing outdoor activities for elderly residents with severely limited mobility may positively affect QOL.11
Some potential limitations should be considered. First, the data in this study were from a self-reported questionnaire. Although most of the responses were fully validated, it is still difficult to predict or estimate the subjective bias of reported data. For example, in the analysis of the reported data, there might be deviations in the actual experience of the participants. Second, the participants were recruited from LTC facilities, and the design considerations of this study could only reflect the view of these ethnic groups. Although the demographic variables, such as the participants’ age, gender, education, and visitation rate, were controlled, caution should be used when generalizing these findings to other settings or to other elderly populations. Third, although the sample size of this study satisfied the requirements for establishing stable person and item estimates and power analysis,16 it is still necessary to study the Chinese version of the PaArticular Scales with a larger sample size to obtain more complete and reliable data. Finally, to ensure that the Chinese version has applicability and generalizability, the samples in future studies should be more representative and more inclusive, for example, additional studies in different domains.
This study demonstrated that the Chinese version of the PaArticular Scales is a reliable and effective tool for measuring the activity and participation of elderly individuals with joint contractures. As a good sound outcome measurement tool, the Chinese version of the PaArticular Scales developed in this study not only fills the gap in assessing the activity and participation of elderly Chinese individuals but also makes the evaluation of elderly individuals with joint contractures more comprehensive, which can be the basis for improving their activity, participation, and QOL. Furthermore, this tool can also be used in the treatment, rehabilitation, prevention, and research programmes of LTC facilities.