The 15-item Chronic Acquired Polyneuropathy Patient-Reported Index (CAPPRI) is a feasible and cost-effective tool for assessing health-related quality of life (eg, pain, sleep, everyday function, and psychological well-being) in patients with diabetic distal sensorimotor polyneuropathy (DSPN), according to a study published in Neurology.
A total of 668 patients with DSPN were recruited for this analysis, all of whom completed CAPPRI scales during clinic visits. Investigators evaluated the performance of the CAPPRI in assessing health-related quality-of-life outcomes in these patients. Items on the assessment included questions about disease frustration and interference, everyday function (eg, walking, getting dressed, performing work, driving, and home activities), sleeping issues, dependency, falling, mental preoccupation with the disease, inability to enjoy leisure activities, energy levels, and eating issues.
Overall, 231 patients with polyneuropathy diagnoses of DSPN completed the 15-item CAPRI scale. The Rasch Partial Credit Model found good person (0.88) and item (0.99) reliability of the scale. In disabled patients, the questions regarding eating and falling were the most sensitive for identifying differences in clinical status; the items associated with pain frustration and interference were most sensitive for the lowest disability levels. The items on CAPPRI with the significantly highest associations for Inflammatory Neuropathy Cause and Treatment scores included questions regarding dependency (P <.001), home activities (P <.001), balance (P <.001), inability to perform leisure activities (P <.001), and falling (P <.001).
The relatively small patient sample, the use of only clinical grounds for diagnosing DSPN, and the inclusion of patients on varying treatment regimens were limitations of this analysis.
Since the CAPPRI met Rasch expectations, the researchers suggest “the scale acts like an interval-level scale, rather than only an ordinal scale.”
Reference
Gwathmey KG, Sadjadi R, Horton WB, et al. Validation of a simple disease-specific, quality-of-life measure for diabetic polyneuropathy: CAPPRI [published online May 4, 2018]. Neurology. doi:10.1212/WNL.0000000000005643