Therapists frequently advise the use of activity pacing as a coping strategy to manage long-term conditions (eg, chronic low back pain, chronic widespread pain, chronic fatigue syndrome/myalgic encephalomyelitis). However, activity pacing has not been clearly operationalized, and there is a paucity of empirical evidence regarding pacing. This paucity of evidence may be partly due to the absence of a widely used pacing scale. To address the limitations of existing pacing scales, the 38-item Activity Pacing Questionnaire (APQ-38) was previously developed using the Delphi technique. The aims of this study were: (1) to explore the psychometric properties of the APQ-38, (2) to identify underlying pacing themes, and (3) to assess the reliability and validity of the scale. Three hundred eleven adult patients with chronic pain or fatigue participated, of whom 69 completed the test-retest analysis. Data obtained for the APQ-38 were analyzed using exploratory factor analysis, internal and test-retest reliability, and validity against 2 existing pacing subscales and validated measures of pain, fatigue, anxiety, depression, avoidance, and mental and physical function. Following factor analysis, 12 items were removed from the APQ-38, and 5 themes of pacing were identified in the resulting 26-item Activity Pacing Questionnaire (APQ-26): activity adjustment, activity consistency, activity progression, activity planning, and activity acceptance. These themes demonstrated satisfactory internal consistency (Cronbach α=.72–.92), test-retest reliability (intraclass correlation coefficient=.50–.78, P≤.001), and construct validity. Activity adjustment, activity progression, and activity acceptance correlated with worsened symptoms; activity consistency correlated with improved symptoms; and activity planning correlated with both improved and worsened symptoms.
Developed to be widely used across a heterogeneous group of patients with chronic pain or fatigue, the APQ-26 is multifaceted and demonstrates reliability and validity. Further study will explore the effects of pacing on patients’ symptoms to guide therapists toward advising pacing themes with empirical benefits.