A unidimensional pain/disability measure for low-back pain syndromes

A new measure is presented, suitable for documenting severity and response to treatment in chronic low-back pain syndromes. It is self-administered and combines two pain and seven mobility items. These were selected from pre-existing validated instruments on the basis of their sensitivity to change after treatment. Their Italian validated translation was adopted. The measure was administered to 32 chronic low-back pain Italian patients, all refractory to previous conservative treatments. In most cases they presented with herniation or protrusion of 1-3 lumbar discs. Patients were treated with 3-6 sessions of autotraction over a 5- to 15-day period. Scores on the scale were recorded at admission, discharge and follow-up, 1-3 months after treatment. At discharge and at follow-up, patients were asked if, overall, they felt improved, the same or worse. At follow-up, 20 patients out of 32 reported overall improvement. Scalometric properties of the measure were tested using Rasch analysis. For admission and follow-up, items followed a consistent hierarchical relationship along a unidimensional pain/disability variable, which is being called back illness. The items were not redundant, in that they spread well along a wide range of difficulty/severity. The hierarchy matched well with the expected expression of the conditions of the patients. A study was conducted on 34 chronic back pain patients, showing satisfactory test-retest reliability. Depending on the various items, Cohen's unweighted K ranged from 0.27 to 0.78, with ten of the 11 items above the 0.45 level of acceptability, while intraclass correlation coefficients ranged from 0.42 to 0.89. At follow-up, changes in BACKILL of plus 15% or more, with respect to admission, were consistent with patients' reports of improvement in 19 out of 20 cases. Changes in BACKILL of less than 15% were consistent with patients reports of being the same or worse in 11 out of 12 cases

Rasch-Derived latent trait measurement of outcomes: insightful use leads to precision case management and evidence-based practices in functional healthcare

The use of Rasch-derived latent trait measurement of outcomes for persons with chronic disease and disablement evolved from other fields, particularly education. Person-metrics is the measurement of how much chronic disease and disablement affects an individual's daily activities physically, cognitively, and through vocational and social role participation. The ability of the Rasch model to assume that the probability of a given person/ item interaction is governed by the difficulty of the item and the ability of the person is invaluable to disability measurement. The difference between raw scores and true measures is illustrated by an example of a patient whose physical difficulty is rated on rising from a wheelchair and walking 100m (known to be more difficult), and then walking an additional 200m. Though number ratings of 0-1-2 are assigned to these tasks, they are not equidistant, and only a true measure shows the actual levels of physical difficulty

Assessment of Disability in Patients with Acute Traumatic Spinal Cord Injury: A Systematic Review of the Literature

Given the importance of accurately and reliably assessing disability in future clinical trials, which will test therapeutic strategies in acute spinal cord injury (SCI), we sought to appraise comprehensively studies that focused on the psychometric properties (i.e., reliability, validity, and responsiveness) of all previously used outcome measures in the SCI population. The search strategy included Medline, CINAHL, EMBASE, and Cochrane databases. Two reviewers independently assessed each study regarding eligibility, level of evidence (using Sackett's criteria), and quality. Of 363 abstracts captured in our search, 36 full articles fulfilled the inclusion and exclusion criteria. Eight different outcome measures were used to assess disability in the SCI population, including Functional Independence Measure (FIM), Spinal cord Injury Measure (SCIM), Walking Index for Spinal Cord Injury (WISCI), Quadriplegia Index of Function (QIF), Modified Barthel Index (MBI), Timed Up & Go (TUG), 6-min walk test (6MWT), and 10-m walk test (10MWT). While 19 of 36 studies provided level-4 evidence, the remaining 17 articles were classified as level-2b evidence. Most of the instruments showed convergent construct validity in the SCI population, but criterion validity was not examined due to the lack a gold standard for assessment of disability. All instruments were tested in the rehabilitation and/or community setting, but only FIM was examined in the acute care setting. Based on our results of quality assessment, the SCIM has the most appropriate performance regarding the instrument's psychometric properties. Nonetheless, further investigations are required to confirm the adequate performance of the SCIM as a comprehensive measure of functional recovery in patients with SCI in rehabilitative care. The expert panel of the Spinal Cord Injury Solutions Network (SCISN) that participated in the modified Delphi process endorsed these conclusions