Graded chronic pain scale revised: validation in a sample of the general German population

The Graded Chronic Pain Scale (GCPS) has been used frequently in pain research and clinical practice to classify chronic pain severity on the basis of pain intensity and pain-related interference.1 To better align with contemporary chronic pain definitions and functional impact metrics, von Korff and colleagues revised the scale (GCPS-R).2 The GCPS-R was developed in adult US enrollees of 2 health plans (n= 2021)2 and subsequently was validated in US veterans (n= 794).3 The authors of the GCPS-R have called for additional confirmatory evidence of the validity of the revised scale in diverse samples.3 The present study was part of a general population survey conducted by the University of Leipzig to assess political attitudes as well as health topics. The participants were informed that the study had no specific focus. They did not receive a reward for participation. Inclusion criteria for the study were age ≥16 years and the ability to read and understand the German language. All participants were informed about the study procedures and signed an informed consent form. The study was approved by the institutional ethics review board of the University of Leipzig (Az 43/24 ek). Chronic pain stages were assessed with the German version of the GCPS-R. The details of the methods for the survey, the translation and blind back-translation, and the data on the predictors of high-impact chronic pain (HICP) have already been published.4 The present study uses the same dataset and extends the previous publication4 with a focus on convergent validity indicators of the GCPS-R. Convergent validity indicators were self-reported limitations on the ability to work, work-related problems, the presence of a chronic illness or long-term health problem, the use of any analgesics and centrally acting analgesics (weak opioids, strong opioids, antidepressants for pain management, anticonvulsants for pain management) during the prior 4 weeks (all self-developed questions), self-perceived health (General Health Question of the 12-Item Short-Form Health Survey),5 and psychological symptom burden (Patient Health Questionnaire 4 [PHQ-4]).6