Assessing patient-reported peripheral neuropathy: the reliability and validity of the European Organization for Research and Treatment of Cancer QLQ-CIPN20 Questionnaire

Abstract

Purpose This clinimetric analysis was conducted to evaluate the reliability, validity, and responsiveness to changeover time of the QLQ-CIPN20 when used to quantify patient-reported chemotherapy-induced peripheral neuropathy (CIPN). Methods Participants recruited to four cooperative group trials were pooled to create two groups (n = 376, 575): those who did versus did not receive neurotoxic chemotherapy. QLQ-CIPN20 internal consistency reliability was assessed using Cronbach's alpha coefficients. Instrument validity was assessed using factor analysis, by evaluating score correlations with other CIPN and pain measures, and by comparing scores between contrasting groups. Cohen's d was used to assess responsiveness to change. Results Alpha coefficients for the sensory, motor, and autonomic scales were 0.88, 0.88, and 0.78, respectively. However, autonomic scale and hearing loss items exhibited low item–item correlations (r ≤ 0.30) and thus were deleted. Moderate correlations were found between QLQ-CIPN20 and Brief Pain Inventory pain severity items (r 0.30–0.57, p ≤ .0001). Correlation between the QLQ-CIPN20 sensory and toxicity grading scale scores was low (r = .20; p ≤ .01). Mean scores were higher (worse) (p ≤ 0.0001) in individuals who did versus did not receive neurotoxic chemotherapy. The sensory and motor scales exhibited moderate-high responsiveness to change (Cohen's d = 0.82 and 0.48, respectively). Factor analysis indicated that the 16-item version formed distinct factors for lower and upper extremity CIPN, delineating typical distal to proximal CIPN progression. Conclusions Results provide support for QLQ-CIPN20 sensory and motor scale reliability and validity. The more parsimonious and clinically relevant 16-item version merits further consideration.

Relationship between Chemotherapy-induced Peripheral Neuropathy and Quality of Life in Patients with Hematologic Malignancies

“…According to the tool's scoring guidelines, the higher the score, the higher the degree of severity of CIPN-related symptoms along a score range of 0-100 [25]. Smith et al, determined the Cronbach's ⍺ coefficient of the 16-item QLQ CIPN20 to be .90 (.84 in our study) for the lower extremity subscale and .91 (.70 in our study) for the upper extremity subscale [24].…”

“…First, this study evaluated only 16 of the 20 original items of the EORTC QLQ-CIPN20 tool [24] as four items were deleted during the validity test. To justify the elimination of these 4 items as non-CIPN-related problems, Smith et al [24]., argued that dizziness, blurred vision, and erectile dysfunction could manifest as a result of non-CIPN-related drugs or comorbid diseases, and hearing loss was likely to occur in patients treated with chemotherapeutics associated with ototoxicity, such as cisplatin, which was not typically administered.…”

“…To justify the elimination of these 4 items as non-CIPN-related problems, Smith et al [24]., argued that dizziness, blurred vision, and erectile dysfunction could manifest as a result of non-CIPN-related drugs or comorbid diseases, and hearing loss was likely to occur in patients treated with chemotherapeutics associated with ototoxicity, such as cisplatin, which was not typically administered. This study included patients with hematologic malignancies and a high possibility of comorbid anemia, a high proportion of elderly patients (47%≥65 years of age), and patients unexposed to chemotherapeutics associated with ototoxicity.…”

“…CIPN was assessed using the 16-item QLQ-CIPN20, which was validated by Smith et al, [24]. The original EORTC QLQ-CIPN20, developed by Postma et al, [2] as a subscale of the European Organization for the Research and Treatment of Cancer quality of life questionnaire core 30 items (EORTC QLQ-30), was comprised of 20 questions (on a 4-point Likert scale) that assessed CIPN, and included 3 subscales to assess motor (8 items), sensory (9 items), and autonomic (3 items) symptoms, as well as function [2].…”

“…and 1 item from the sensory scale (Did you have difficulty hearing?) were eliminated from the 20-item original tool because of low inter-item correlations [24]. A factor analysis performed after omitting these 4 yielded 2 factors, the "lower extremity CIPN" and "upper extremity CIPN" subscales.…”