What is “normal” disability? An investigation of disability in the general population

Abstract

Many studies have investigated the highly relevant association between pain and disability in clinical groups using the Pain Disability Index (PDI). To interpret these results, knowledge of disability in the general population is crucial. Moreover, to investigate criterion validity of the PDI, the influence on health care utilisation (HCU) is of special interest. In the present study, a broadened version of the PDI was psychometrically evaluated with a large representative sample of the general population. The independent impact of disability on HCU was also investigated. A representative sample of the German general population (N=2510) was screened for disability, somatic complaints, mental health (PHQ) and HCU. Following a psychometric evaluation of the PDI, data are provided about the distribution of disability in the general population. For the prediction of HCU, stepwise linear regression analysis was calculated. The psychometric evaluation of the PDI revealed a one-factor solution, high reliability, and satisfactory construct validity. Percentage scores for the distribution of disability are provided for those people reporting at least one pain/somatic symptom. These data allow a better description of disability in clinical samples. Somatic complaints, disability, unemployment or retirement, depression and anxiety explained 26% of the variance for HCU. The PDI is an economical, reliable and valid self-rating instrument for assessing disability caused by physical symptoms. HCU in the general population is determined by the number and severity of somatic complaints and also by disability. Symptoms and disability play a crucial but somewhat independent role.

Physiotherapy triage assessment of patients referred for orthopaedic consultation – Long-term follow-up of health-related quality of life, pain-related disability and sick leave

“…These findings differ from those previously reported; that many patients with persistent pain experience a high level of disability, affecting both work capacity (Gureje, Simon, 2001;Gerdle et al, 2004;Landmark et al, 2013) and quality of life (Kroenke et al, 2013;Landmark et al, 2013). However, Mewes et al (2009) report that approximately 30% of the general population with one or more somatic complaints indicated no disability on the PDI. Furthermore, Denison et al (2007) presented three subgroups of patients with musculoskeletal pain in primary care, where the largest group reported low levels of pain and mean score on PDI, as well as low levels of fear of movement, and a high level of selfefficacy.…”

Internet-Based Cognitive-Behavioural Intervention for Women with Premenstrual Dysphoric Disorder: A Randomized Controlled Trial

“…It encompasses 7 items that are answered on an 11-point Likert scale ranging from 0 (no disability) to 10 (total disability). As in previous studies in the field of behavioural medicine [39], the instruction text was modified by replacing the word pain by “premenstrual syndrome” or synonyms. In the current sample, adequate reliability for the PDI was demonstrated with Cronbach’s α of 0.83, which is comparable with an internal consistency value in a previous validation study (Cronbach’s α of 0.87 [38]).…”

Evaluating New Proposals for the Psychiatric Classification of Patients With Multiple Somatic Symptoms

“…Symptom-associated disability was assessed using the Pain Disability Index (PDI) in its modified version asking for disability caused by symptoms in general (not only pain) (27). This is a frequently used instrument in pain research, and we were able to collect normative data from 2500 people in the general population.…”