title: Self-reported pain severity, quality of life, disability, anxiety and depression in patients classified with 'nociceptive', 'peripheral neuropathic' and 'central sensitisation' pain. The discriminant validity of mechanisms-based classifications of low back (±leg) pain.
abstract: Evidence of validity is required to support the use of mechanisms-based classifications of pain clinically. The purpose of this study was to evaluate the discriminant validity of 'nociceptive' (NP), 'peripheral neuropathic' (PNP) and 'central sensitisation' (CSP) as mechanisms-based classifications of pain in patients with low back (±leg) pain by evaluating the extent to which patients classified in this way differ from one another according to health measures associated with various dimensions of pain. This study employed a cross-sectional, between-subjects design. Four hundred and sixty-four patients with low back (±leg) pain were assessed using a standardised assessment protocol. Clinicians classified each patient's pain using a mechanisms-based classification approach. Patients completed a number of self-report measures associated with pain severity, health-related quality of life, functional disability, anxiety and depression. Discriminant validity was evaluated using a multivariate analysis of variance. There was a statistically significant difference between pain classifications on the combined self-report measures, (p = .001; Pillai's Trace = .33; partial eta squared = .16). Patients classified with CSP (n = 106) reported significantly more severe pain, poorer general health-related quality of life, and greater levels of back pain-related disability, depression and anxiety compared to those classified with PNP (n = 102) and NP (n = 256). A similar pattern was found in patients with PNP compared to NP. Mechanisms-based pain classifications may reflect meaningful differences in attributes underlying the multidimensionality of pain. Further studies are required to evaluate the construct and criterion validity of mechanisms-based classifications of musculoskeletal pain.
authors.affiliation: St Vincent's University Hospital, Elm Park, Dublin 4, Ireland. k.smart@svuh.ie
authors.forename: Keith M
authors.initials: KM
authors.lastname: Smart
authors.forename: Catherine
authors.initials: C
authors.lastname: Blake
authors.forename: Anthony
authors.initials: A
authors.lastname: Staines
authors.forename: Catherine
authors.initials: C
authors.lastname: Doody
mesh_terms: D000704:Analysis of Variance; D001007:Anxiety / Q000453:epidemiology*; D059333:Central Nervous System Sensitization / Q000502:physiology*; D003430:Cross-Sectional Studies; D003863:Depression / Q000453:epidemiology*; D004185:Disability Evaluation; D016002:Discriminant Analysis; D005260:Female; D006801:Humans; D007866:Leg / Q000503:physiopathology*; D017116:Low Back Pain / Q000145:classification* / Q000503:physiopathology / Q000523:psychology*; D008297:Male; D059352:Musculoskeletal Pain / Q000145:classification* / Q000503:physiopathology / Q000523:psychology*; D010147:Pain Measurement / Q000379:methods; D010523:Peripheral Nervous System Diseases / Q000145:classification* / Q000503:physiopathology / Q000523:psychology*; D011788:Quality of Life