Translation and linguistic validation of the Persian version of the patient assessment of upper gastrointestinal symptom severity index and quality of life

Abstract

AIM: This study aimed to ascertain the equivalence in meaning and measurement qualities of two assessment tools, namely the Patient Assessment of Upper Gastrointestinal Symptom Severity Index (PAGI-SYM) and Quality of Life (PAGI-QOL), in a sample of individuals with upper gastrointestinal disorders in Iran. BACKGROUND: There is substantial demand for reliable and accurate research instruments in researchers' native language to evaluate specific concepts of interest. METHODS: The Rome Foundation Guideline was employed as a framework for this investigation. To this end, a rigorous translation process was utilized, involving forward translation by two independent translators, reconciliation, and backward translation. An expert committee evaluated the semantic, idiomatic, experiential, and conceptual aspects of the translations. A panel of gastroenterologists assessed the content and face validity of the translated questionnaires. Cognitive debriefing sessions were conducted involving patients with dyspepsia or gastroesophageal reflux disease. Concurrent validity of the questionnaires was ascertained by comparing them with the 36-item Short Form Health Survey (SF-36). RESULTS: The findings presented satisfactory translation of the assessment tools, with initial assessments of internal consistency and construct validity demonstrating suitability. In this particular sample, the internal consistency of the PAGI-SYM was excellent (Cronbach's alpha range: 0.62-0.92), while the PAGI-QOL indicated good internal consistency (Cronbach's alpha range: 0.68-0.95). Further, there were strong correlations between the total scores of PAGI-SYM and PAGI-QOL, as well as all SF-36 general health subscale (-0.469 and 0.572, p-value<0.001), demonstrating concurrent validity. CONCLUSION: Both PAGI-QOL and PAGI-SYM instruments exhibited validity and reliability when applied to assess upper gastrointestinal disorders.