Reliability and validity of The University of California, scleroderma clinical trial consortium gastrointestinal tract questionnaire (ucla SCTC git 2.0) for Turkish population

Abstract: Objectives: The UCLA Scleroderma Clinical Trial Consortium Gastrointestinal Tract Instrument (UCLA-SCTCGIT) 2.0 was developed to assess systemic sclerosis (SSc) associated gastrointestinal tract (GIT) symptoms severity and its impact on patients' well-being. Our objective was to translate the UCLA-GIT 2.0 from English to Turkish and to validate it among Turkish systemic sclerosis (SSc) patients. Methods: UCLA-GIT 2.0 was adapted into Turkish using a formal forward-backward translation method. The resulting Turkish GIT 2.0 in combination with Short Form 36 (SF-36) was administered to 97 Turkish speaking patients with SSc. We evaluated the internal consistency reliability and construct validity by exploring associations between the UCLA SCTC GIT 2.0 and SF-36 scales. Internal consistency was determined by calculating Cronbach's alpha. To determine the reliability, the questionnaire was re-administered with an interval of two weeks to a subgroup of patients and the intraclass-correlation coefficient (ICC) was computed. Spearman correlation coefficients between GIT scores and SF-36 were computed. Results: Ninety seven patients with a mean age of 55.37 ± 11.35 years and predominantly female (87,6%) were included. Cronbach's alfa value was 0.894 for UCLA SCTC GIT 2.0 scale. Intraclass correlation coefficient score for test-retest reliability was determined ,821 (p=0,000). The instrument had acceptable reliability except for the diarrhoea scale (alpha=,356). Moderate magnitude correlations were determined between total GIT score and SF-36 subscales. Conclusions: The Turkish GIT 2.0 questionnaire showed good internal consistency, high reliability and acceptable validity. Key words: scleroderma, gastrointestinal truct, validity, reliability