The Pain Disability Questionnaire (PDQ): evaluating the efficacy of the psychosocial and functional subscales for 12-month post-treatment outcomes after total knee arthroplasty

Abstract

Background: The Patient Disability Questionnaire (PDQ) has been shown to have good predictive validity for outcomes after total hip arthroplasty (TKA). However, the PDQ subscales (psychosocial and functional disability) have not been assessed independently. This study assesses 1-year surgical outcomes based on the PDQ’s psychosocial and functional disability subscale scores. Methods: The sample included 130 participants undergoing TKA. Physical and psychosocial measures included the PDQ, Knee Society Score (KSS), Western Ontario McMaster Arthritic Index (WOMAC), and the Short Form-36 Health Inventory (SF-36). Univariate correlations were used to cross-validate all subscales. Multivariate gamma and linear regressions were used to associate PDQ functional and psychosocial disability subscale scores with WOMAC and SF-36, 1 yr after TKA. Results: Poorer PDQ psychosocial scores were associated with being younger, black or Hispanic, and using Medicaid. Poorer functional disability scores were associated with being younger, female, black or Hispanic, and using Medicaid or without insurance. Multivariate regressions revealed that baseline PDQ psychosocial and functional disability were both significantly associated with 1-year WOMAC total scores and 1-year SF-36 Mental Composite Scores. Conclusions: The PDQ is useful in predicting 1-year outcomes for patients undergoing TKA. Worse baseline PDQ subscale scores indicated worse quality of life, more pain and stiffness of the joints, as determined by comparative WOMAC and SF-36 scores. Clinical implications from this study suggest screening patients before surgery to identify factors that could hinder recovery time or cause pain or function remission in adults undergoing TKA.

Assessing the Functional Status of Patients with Chronic Pain—Cross Cultural Adaptation and Psychometric Properties of the Serbian Version of the Pain Disability Questionnaire

“…It is necessary to separately evaluate pain intensity and functionality, as improvements in pain intensity do not necessarily lead to improvements in function [ 43 ]. However, a significant correlation was identified between pain intensity and the PDQ-Serb, confirming results found in previous studies [ 7 , 9 , 12 ].…”

“…Total score differences have distinguished between different subject groups with presumably different levels of disability (e.g., chronic pain, acute pain, and control subjects) [ 7 , 8 ]. The PDQ has shown strong associations with other patient-reported measures of perceived disability, physical/mental functioning, pain interference, quality of life, and pain severity [ 7 , 8 , 9 , 10 , 11 , 12 ]. Associations have also been found with objective markers of physical impairment in subjects with chronic pain conditions, including distance and speed in a 6 minute walk test [ 13 ] and length of disability following workers compensation injuries [ 14 ].…”

“…It has demonstrated responsiveness to rehabilitative treatment with significant reductions in total and subscale scores [ 7 , 14 ]. Total PDQ scores have also predicted one-year post-rehabilitation work return/retention and health-utilization outcomes [ 7 ] and one-year post-total knee arthroplasty pain, quality of life, and functional outcomes [ 10 , 12 ].…”

“…Though most previous studies have assessed total PDQ scores, some have also used the lower-order factors as subscale scores [ 7 , 12 ]. The specific predictive power of the two subscales has not been adequately addressed.…”