Psychometric properties of the Dutch version of the revised neurophysiology of pain questionnaire

BACKGROUND: Understanding pain and its mechanisms can play an important role in (post-) cancer rehabilitation. In order to test patient's knowledge of pain, the Revised Neurophysiology of Pain Questionnaire was developed and translated into Dutch (RNPQ-NL). However, its psychometric properties have not been examined yet.

OBJECTIVE: The goal is to examine the psychometric properties of the RNPQ-NL as a tool to measure the knowledge of pain; in addition, its cross-cultural validity between Belgian and Dutch participants is examined.

METHODS: 277 persons from Belgium and the Netherlands participated in this study. Cancer patients and survivors (CPaS) (n = 115) were compared to a group of experts with medical training (n = 97). Highly educated individuals without medical background (n = 65) served as control group. The RNPQ-NL was filled out twice and scores analysed in accordance with the COSMIN-recommendation for assessing the methodological quality of studies on measurement properties of health status instruments.

RESULTS: The RNPQ-NL was able to distinguish between high and low knowledge of pain. The CPaS group scored significantly lower on the RNPQ-NL compared to the expert group (p < 0.001), but not in comparison to the control group (p=1.00). The Belgian CPaS scored lower than the Dutch CPaS (p=0.001), with a medium effect size (d = 0.481), showing acceptable cross-cultural validity. The Cronbach's α was 0.625, showing some heterogeneity of the items. The test-retest reliability was adequate (ICC = 0.794).

CONCLUSION: This study supports the interpretability, test-retest reliability, discriminative, and cross-cultural validity of the RNPQ-NL. Internal consistency is suboptimal but acceptable for measuring the knowledge of pain in CPaS.