Functional limitations in children and adolescents suffering from chronic pain: validation and psychometric properties of the German Functional Disability Inventory (FDI-G)

Abstract

Our objective was to translate the Functional Disability Inventory (FDI) into German, to evaluate its validity and to assess functional limitation in a large cohort of children and adolescents with juvenile fibromyalgia syndrome (jFMS). We administered several questions (e.g., sociodemographics, school-related issues) and questionnaires to 329 patients and one parent. The questionnaires included, among others, a German version of the FDI, the CHAQ (parent report), KIDSCREEN, tender point score (TPS), Depression Inventory for Children and Adolescents (DIKJ) and others. Patients were asked about the severity of pain today (NRS = numerical rating scale) and other symptoms. Internal consistency was evaluated with Cronbach's alpha. Construct validity of the FDI was evaluated by correlating the FDI with the questionnaires as well as with the pain and other variables, e.g., days missed school. An exploratory factor analysis (EFA) was also performed. Mean age was 13.9 years (SD ±2.48). Means were for pain today 5.37 (±2.39) and for the TPS 39.71 (±21.56). Internal consistency was α = .90. Low-to-moderate correlations were obtained between the FDI and the CHAQ (ρ = .51**), KIDSCREEN (e.g., physical well-being ρ = -.62**; peers and social support ρ = -.28**) as well as the pain variables (NRS ρ = .24**; TPS ρ = .38**). Psychological variables were also correlated with the FDI (e.g., DIJK ρ = .28**). An EFA suggested a two-factor solution. The FDI is a valid instrument for measuring functional limitations in German children and adolescents with jFMS.

Pain, functional disability, and their Association in Juvenile Fibromyalgia Compared to other pediatric rheumatic diseases

“…This study further confirms that severe pain and impairment in functioning is typical in youth with JPFS who are seen in pediatric rheumatology clinics. This is a common observation in research on youth with idiopathic chronic musculoskeletal pain [4,6,25,26]. A distinguishing feature of the current study, however, is that uniformly collected data were aggregated into a registry from multiple sites across North America.…”

Prevalence of Juvenile Fibromyalgia Syndrome Among Children and Adolescents and its Relationship With Academic Success, Depression and Quality of Life, Çorum Province, Turkey

“…27 In common with other patients with chronic pain, previous research demonstrated that individuals with JFMS experience decreased QoL. 28 For example, Durmaz et al 7 found a significantly lower QoL in children with JFMS. Kashikar-Zuck et al 29 reported significant difficulty in daily QoL in adolescents and children with chronic pain, such as JFMS and back pain.…”

Longitudinal Resilience and Risk Factors in Pediatric Postoperative Pain (LORRIS): Protocol for a Prospective Longitudinal Swiss University Children’s Hospitals-Based Study

“…Functional disability: Children’s self-reported difficulty in physical and psychosocial functioning due to their physical health is assessed by the Functional Disability Inventory. 54 15 items are rated on a Likert scale from 0 (=no problems) to 4 (=not possible) and concern perceptions of activity limitations during the past 2 weeks. Higher scores indicate greater disability.…”