Turkish translation and validation of the Xerostomia Inventory

Abstract

Objectives: The Xerostomia Inventory (XI) was developed to assess the severity of dryness in patients with xerostomia. It has a long and a short form with three- and five-point Guttman-type response options. In this study, we aimed to translate the XI into Turkish, to assess the validity and reliability of both response options in patients with head & neck cancer (HNC) or Sjögren syndrome (SS), and to select the optimal version for Turkish patients.

Patients and methods: Between January 2019 and June 2019, the XI was translated into Turkish (XI-T) and applied to patients aged ≥18 years with HNC and SS. All patients were applied two tests including both the three- and five-point options. The internal consistency was assessed by Cronbach alpha and test-retest reliability by intraclass correlation coefficients (ICCs). Content validity was based on expert opinion and patient reviews.

Results: A total of 186 patients (109 males, 77 females; median age: 54 years; range, 19 to 78 years) answered the XI-T. The number of patients with HNC and SS was 143 (77%) and 43 (23%), respectively. Median XI-T score was 17 for the three-point, and 24 for the five-point option, respectively. Overall internal consistency was satisfactory for both options (α=0.81 and α=0.89, respectively). Overall test-retest reliability was satisfactory and ICCs ranged between 0.71 and 0.92 for the three-point, and 0.36 and 0.94 for the five-point option, respectively. Assessments based on expert opinions and patient reviews also favored the content validity of the scale.

Conclusion: The XI-T with both three- and five-point options is a valid and reliable tool to evaluate the presence and severity of dryness in patients with HNC and SS who experience xerostomia. The three-point option is more comprehensible and can be preferred over the five-point option in the Turkish population.

Citation: Yüce Sarı S, Tuğce Yılmaz M, Elmalı A, Kılıç L, Yüce D, Özyiğit G, et al. Turkish translation and validation of the Xerostomia Inventory. Arch Rheumatol 2022;37(3):351-360.

The study protocol was approved by the Hacettepe University Faculty of Medicine Ethics Committee for Non-Invasive Clinical Research (date, no: 15 Jan 2019, no: 2019/06-13). The study was conducted in accordance with the principles of the Declaration of Helsinki.

A written informed consent was obtained from each participant.

Data Sharing Statement:
The data that support the findings of this study are available from the corresponding author upon reasonable request.

Material preparation, data collection, analysis: S.Y.S., M.T.Y., A.E., L.K.; Data collection, analysis, revision: D.Y.; Revision, analysis: G.Ö., M.C.; Materials preparation, revision, analysis: G.Y.

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

The authors received no financial support for the research and/or authorship of this article.