Study design and sample
This study was designed as a cross-sectional survey. It was approved by
the XXX Research Ethics Committee (No. 201905XXXXX), and official
written consent from each facility was obtained. Prior to the study, the
research process was explained in detail to the participants. During the
period from April to June 2019, random sampling was performed using the
multi-stage sampling method. For factor analysis, the sample size for
items must be 5-10 according to previous studies.14,15The Chinese PaArticular Scales have a total of 35 items; therefore, a
sample size of 175-350 participants was appropriate for factor analysis
in this study.16 The inclusion criteria of the
participants were as follows: (1) ≥ 65 years old; (2) more than 6 months
living at the facility; (3) having the language skills to fill out or
answer the questionnaire; (4) severe joint contractures in any one
important joint (knee, hip, ankle, shoulder, elbow and hand) with
confirmation from a doctor, a nurse, or a therapist. Severe joint
contractures were defined as 3 on a 4-point scale (loss >
2/3 of joint range of motion).17,18 Those with
cognitive impairment and major mental illness diagnosed by physicians
were excluded.