The Pain Disability Index: psychometric properties

Abstract

This paper reports two studies of chronic pain patients (n = 444) relevant to the psychometric properties of the Pain Disability Index (PDI), a self-report instrument that has been used to assess the degree to which chronic pain interferes with various daily activities. In the first study, patients with high PDI scores reported more psychological distress (P less than 0.001), more severe pain characteristics (P less than 0.001), and more restriction of activities (P less than 0.001) than patients with low PDI scores, findings supportive of the construct validity of the measure. Further, a multiple regression showed that a linear combination of 9 variables predicted PDI scores (R = 0.74): time spent in bed, psychosomatic symptoms, stopping activities because of pain, work status, pain duration, usual pain intensity, quality of life, pain extent, and education. This study also showed differences for age and gender on disability. The second study involved 46 patients who had undergone inpatient treatment for their pain conditions. The study revealed modest test-retest reliability for the instrument. It also showed the PDI to be associated with the levels of pain behavior exhibited by these patients. The findings of both studies generally support the reliability and validity of the PDI as a brief measure of pain-related disability. Questions regarding its test-retest reliability and lack of association with certain pain behaviors are discussed, as are suggestions for future research.

Two Psychological Interventions Are Effective in Severely Disabled, Chronic Back Pain Patients: A Randomised Controlled Trial

“…The PDI is a measure of interference of chronic pain with functioning in each of seven life areas, generating a maximum global disability score of 7. The PDI is associated with measures of pain severity, affective distress and activity restriction, and has good psychometric properties [22]. Health-related quality of life was assessed by Health-Related Life Satisfaction Scale (FLZ) [23] (e.g.…”

Effects of Neck-Specific Exercises Compared to Waiting List for Individuals With Chronic Whiplash-Associated Disorders: A Prospective, Randomized Controlled Study

“…The Pain Disability Index (PDI) [30] measures the impact that pain has on the ability of a person to participate in essential life activities and has been shown to be reliably measure. Activities are scored on a numeric scale that ranged from 0 (no disability) to 10 (worst disability).…”

A telephonic intervention for promoting occupational re-integration in work-disabled individuals with musculoskeletal pain

“…Self-reported disability-The measure of selfreported disability was a modified version of the Pain Disability Index [38]. As with other measures, the instructional set was modified to refer to "symptoms of your condition" as opposed to pain.…”