Psychometric properties of the Brazilian short-version of the Northwick Park Neck Pain Questionnaire.

ABSTRACT

OBJECTIVE: To translate, cross-culturally adapt and assess measurement properties of the translated version of the Northwick Park Neck Pain Questionnaire into Brazilian Portuguese. DESIGN: Cross-sectional study. SETTINGS University healthcare facility and online. PARTICIPANTS: People with chronic neck pain (n = 178). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Participants answered the translated version of Northwick Park Neck Pain Questionnaire, the Neck Disability Index, the Numerical Rating Scale for pain, the Tampa Scale for Kinesiophobia and the Pain Catastrophizing Scale. Seven to ten days after that, a subset of 84 participants answered the Northwick Park Neck Pain Questionnaire again. The structural (exploratory and confirmatory factor analyses) and construct validities, internal consistency, reliability and concordance were assessed. Level of significance was set at 5%. RESULTS: Participants' (35.6 ± 13.5 years old) with symptoms duration of 54.4 ± 60.4 months scored 25.5 ± 14.0 on the Brazilian Northwick Park Neck Pain Questionnaire and 11.9 ± 5.8 on the Neck Disability Index. The structural analysis showed that the short version of the Northwick Park Neck Pain Questionnaire has an adequate structure to measure disability due to neck pain. Correlations with other questionnaires were between 0.268 and 0.678, Cronbach's alfa was 0.76, intraclass correlation coefficient was 0.96, standard error of measurement was 2.74 and minimal detectable change was 7.60. CONCLUSION: The short version of the Northwick Park Neck Pain Questionnaire is valid and reliable to be used in patients with chronic neck pain, as it presented adequate measurement properties of structural and construct validity, reliability and concordance.