Observational Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Jan 18, 2019; 10(1): 23-32
Published online Jan 18, 2019. doi: 10.5312/wjo.v10.i1.23
Validation of the Danish version of the musculoskeletal tumour society score questionnaire
Casper Kloster Pingel Saebye, Johnny Keller, Thomas Baad-Hansen
Casper Kloster Pingel Saebye, Johnny Keller, Thomas Baad-Hansen, Sarcoma Centre of Aarhus University Hospital, Department of Orthopedic Surgery, Aarhus University Hospital, Aarhus N 8200, Denmark
Author contributions: Saebye CKP collected the majority of the data; Saebye CKP, Keller J and Baad-Hansen T designed the study and analyzed the data; Saebye CKP, Keller J and Baad-Hansen T wrote the manuscript.
Institutional review board statement: The study was preapproved in accordance with the national ethical guidelines, since this type of study does not require approval in Denmark, furthermore the study is in accordance with the Helsinki Declaration.
Informed consent statement: All patients gave their verbally informed consent for participating in the study, however signed consent was not required according to Danish guidelines, since the study was based on questionnaires.
Conflict-of-interest statement: All authors declare: no support from any organization for the submitted work; no financial relationships with any organizations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Casper Kloster Pingel Saebye, MD, PhD, Doctor, Sarcoma Centre of Aarhus University Hospital, Department of Orthopedic Surgery, Aarhus University Hospital, Palle Juul-Jensens Blvd. 99, Aarhus N 8200, Denmark. caspersaebye@clin.au.dk
Telephone: +45-78450000
Received: August 24, 2018
Peer-review started: August 24, 2018
First decision: October 4, 2018
Revised: December 1, 2018
Accepted: December 12, 2018
Article in press: December 13, 2018
Published online: January 18, 2019
Abstract
BACKGROUND

The musculoskeletal tumour society score (MSTS) is a well-known questionnaire for measuring functional outcome in patients with neoplasms in the extremities. Standardized guidelines for cross-cultural translation and validation ensure the equivalence of content between the original and translated versions. The translation and validation provide the possibility to compare different sarcoma populations on an international level. This study is based on the hypothesis that the Danish MSTS questionnaire is a valid tool for measuring the end result after surgery for neoplasms in the extremities.

AIM

To validate the Danish version of the upper and lower extremity version of the MSTS.

METHODS

The translation of the MSTS was conducted in accordance with international guidelines. Patients operated for sarcomas and aggressive benign tumors were invited to participate in the study. The psychometric properties of the Danish version of the MSTS were tested in terms of validity and reliability and for the risk of floor or ceiling effect. Spearman’s rank coefficient was used to test the validity by comparing with the Toronto Extremity Salvage Score (TESS). The Intraclass Correlation Coefficient (ICC) was used to evaluate inter-rater reliability. Cronbach’s alpha was used to test for internal consistency. Spearman’s rank coefficient was used to compare the MSTS lower extremity version with the objective test, Timed Up and Go (TUG).

RESULTS

The upper extremity version demonstrated an ICC of 0.95 in the inter-rater reliability test. The lower extremity version had an ICC of 0.88 in the inter-rater reliability test, respectively. Both MSTS versions showed a ceiling effect. The validity of the MSTS was measured by Spearman’s rank correlation coefficient by comparing the MSTS with the TESS and found it to be of 0.80 (P < 0.01) and 0.83 (P < 0.01) for the upper extremity and lower extremity version, respectively. A Spearman’s rank correlation coefficient of - 0.26 (P < 0.01) was found between the TUG and the MSTS questionnaire. A Spearman’s rank correlation coefficient of - 0.38 (P < 0.01) was found between the TUG and the lower extremity version of the TESS questionnaire.

CONCLUSION

The Danish version of the MSTS questionnaires were found to have good reliability and validity, however a substantial ceiling effect was identified.

Keywords: Sarcoma, Patient outcome assessment, Clinical oncology, Surgical oncology, Patient satisfaction

Core tip: The Danish version of the musculoskeletal tumour society score (MSTS) was found to have an overall good reliability and validity, however a substantial ceiling effect as well as a possibility of measurement error in the MSTS score was found. These findings must be taken into consideration when using the MSTS questionnaire.