Construct and criterion-based validity of brief pain coping scales in persons with chronic knee osteoarthritis pain

A recent trend in clinical practice is to adopt short screening and diagnostic self-report instruments for patients with chronic pain. Brief two-item pain coping and beliefs measures have recently been developed and have potential to improve decision making in clinical practice. Our study examined the construct and criterion-based validity of the two-item per scale version of the coping strategies questionnaire (CSQ).

We used data obtained on a community-based sample of 873 persons with chronic knee osteoarthritis pain from the Osteoarthritis Initiative, a large longitudinal cohort study. Persons were administered the two-item per scale version of the CSQ. The International Classification of Functioning framework was used to select a variety of criterion-based measures for comparison with the CSQ. Spearman correlations and hierarchical regression models were used to characterize construct validity and receiver operating characteristic (ROC) curves, sensitivity and specificity were used to describe criterion-based validity.

Construct validity of the CSQ scales was generally supported, with the Catastrophizing and Praying or Hoping scales demonstrating the strongest construct validity across criterion measures. Criterion-based validity for the CSQ scales varied depending on the criterion measure. The Catastrophizing and Praying or Hoping scales also had the strongest criterion-based validity, with ROC curve areas as high as 0.71 (95% confidence interval = 0.67, 0.75), P < 0.001, for identifying persons with substantial physical function deficits.

The findings suggest that several of the two-item CSQ scales demonstrate a modest level of construct validity along with fair criterion-based validity. The Catastrophizing and Praying or Hoping scales appear to hold the most promise for clinical applications and future longitudinal research.