VALIDITY AND RELIABILITY OF THE GREEK VERSION OF THE PAIN BELIEFS AND PERCEPTIONS INVENTORY

A. Christakou^1,2, V. Sakellari¹

Background: Beliefs of chronic pain play an important role in experiencing, assessing and treating chronic pain. The Pain Beliefs and Perceptions Inventory (PBPI) has been used widely to evaluate pain perceptions and beliefs of patients with chronic pain (Williams and Thorn, 1989).

Purpose: To investigate:
(a) the face and content validity,
(b) the factor structure,
(c) the concurrent validity,
(d) the discriminant validity,
(e) the internal consistency and the test-retest reliability of the PBPI in a Greek population with chronic pain.

Methods: The PBPI is a 16-item self-administered Likert-type scale addressing 4 dimensions of pain beliefs: seeing pain as mysterious (Mystery subscale), holding oneself responsible for pain (Self-Blame subscale), regarding one’s condition as lingering in the future (Permanence subscale), and/or continuous over time (Constancy subscale). Each item had a score ranged from −2 to +2, without a 0 value. The questionnaire was administered in 174 participants (117 women, 57 men) with an average age of 45.52 years (SD= 14.18) with chronic low back pain, neck pain, and/or pain of limbs lasting for at least 6 months (M=34.35, SD=39.37). Exploratory factor analysis (EFA) was chosen to examine the factor structure of the PBPI. A number of valid constructs were used to assess the concurrent and discriminant validity of the PBPI. The reliability of the instrument was examined using Cronbach α and Pearson r (ICC).

Results: The translation of the instrument was examined by physiotherapists and an expert in psychometrics. The instrument was found to include necessary questions for creation of an accurate impression of the degree of pain beliefs. The translation of the PBPI seemed to be valid and the instrument was well accepted by all the patients. Principal Axis Factoring (PAF) was the factor extraction method which has been used to analyze the factor structure of the PBPI. PAF method showed a fourth-factor solution with eigenvalues from 4.205 to 1.695, which accounted for 66.353% of the total variance. The communalities of the 16 items ranged from 0.385 to 0.939 with a mean number of 0.663. The factor loadings of the items from the pattern matrix ranged from 0.728 to 0.975. The first factor (Mystery), second factor (Constancy), third factor (Permanence), fourth factor (Self-blame) consisted of four, five, four and three items, respectively. The concurrent and discriminant validity of the instrument was confirmed by examining correlations between the PBPI with Short - form McGill Pain Questionnaire (SF-MPQ), Present Pain Intensity (PPI) index, Visual Analogue Scale (VAS), Brief Pain Inventory (BPI), Marlowe-Crowne Social Desirability Scale (SDS). The Cronbach α and the ICCs indices of the PBPI were acceptable.

Conclusion(s): The Greek translation of the PBPI provided reliable and valid instrument for the valuation of Greek patients with chronic pain.

Implications: These results make available a suitable instrument for chronic pain in the Greek population and will facilitate cross-cultural research on pain beliefs in the future.

Funding, acknowledgements: No external funding

Keywords: Chronic musculoskeletal pain, Validity and reliability, Greece

Topic: Pain & pain management

Did this work require ethics approval? Yes

Institution: Department of Physiotherapy, Technological Educational Institute of Lamia

Committee: Department of Physiotherapy, Technological Educational Institute of Lamia

Ethics number: Department of Physiotherapy, Lamia TEI