Confirmatory factor analysis of the Pittsburgh Sleep Quality Index in rheumatoid arthritis patients.

The purpose of this research was to evaluate the factor structure of the Pittsburgh Sleep Quality Index (PSQI) in rheumatoid arthritis (RA). The sample included 107 patients with RA, 88 females and seven males, with an average age of 56.09 years, recruited from the greater Southern California area.

A multidimensional model of fatigue in patients with rheumatoid arthritis.

Objective: To evaluate a multidimensional model testing disease activity, mood disturbance, and poor sleep quality as determinants of fatigue in patients with rheumatoid arthritis (RA).

Method: The data of 106 participants were drawn from baseline of a randomized comparative efficacy trial of psychosocial interventions for RA. Sets of reliable and valid measures were used to represent model constructs.

An evaluation of a biopsychosocial framework for health-related quality of life and disability in rheumatoid arthritis.

Objective: To examine the relationships between physical, psychological, and social factors and health-related quality of life (HRQOL) and disability in rheumatoid arthritis (RA).

Methods: A sample of 106 patients with rheumatoid arthritis (RA) completed measures of self-reported disease activity and psychosocial functioning, including coping, personal mastery, social network, perceived stress, illness beliefs, the SF-36 and Health Assessment Questionnaire Disability Index (HAQ-DI). In addition, physician-based assessment of disease activity using the Disease Activity Scale (DAS-28) was obtained.