Translation and Cross Cultural Adaptation and Final Validation of Questionnaire on Assessment of Nutritional Status of Cancer Patients

Abstract

A Scored Patient- Generated Subjective Global Assessment for the first time for a complete nutritional status PG-SGA was published by Faith Ottery in 1996. This publication provides nutritional intervention and guidelines for assessment (combined with triage opportunities) geared towards nutritional recommendations for prevention and treatment of cancer patients. The use of the PG-SGA as a tool in research and clinical studies has been confirmed and recommended. There has been no Persian language version of this questionnaire in existence as a tool adapted to Iranian nutritional culture which could be used as a valid and acceptable publication. In order to use PG-SGA tool as a required tool domestically, the English version of the questionnaire needed to be adopted and conditioned for national cultural necessities in all possible ways for its correct and right application for clinical and research studies nationally. Therefore, the main purpose of this study is to bring cross cultural adaption and local nutritional elements and tailor fit them using PG-SGA tool only as a guideline. Methods: Using ISPOR (International Society for Pharmacoeconomics and Outcome Research) approach as a guideline, the procedure of translation and cross cultural adaption on preparing PG-SGA tool was done applying the ten following considerations, namely: Basic preparation, forward translation (from English to Persian), integration and reconciliation, Back Translation , Review and correction of Persian translation to English, harmonization and unification of local factors involved, cognitive debriefing of final results, further correction and final report. For the sake of content validity of Persian version of PG-SGA and its reliability (Relevancy, comprehensibility and items difficulty), face and structural content validity (Exploratory Factor Analysis) approach was used. For reliability of the Persian tool, the Test and Retest method as well as intraclass correlation coefficient (ICC) was used. For similarity and internal consistency , Cronbach Alpha Coefficient method was applied. Findings: The process of translation and cross cultural adaptation before mentioned were successfully carried out and accomplished. The assessment tool now is available for all concerned patients 100% nationwide. In terms of content validity from the viewpoints of professionals in the field, the designed tool based on its ease of understanding, difficulty, and connectivity order scores : S-CI=0/94, S-DI=0/84 and S-CVI=0/92 respectively with a total content validity Index of (Total. CVI=0/9). The Face validity was approved to be 100%. The designed and prepared tool scored ICC=0/84 with CI :( /061-0/94) in reliability measurement by Test and Retest method and in terms of Internal Consistency using Cronbach Alpha Coefficient a score of 0/6 was obtained. In search for Structural Validity using EFA (Exploratory Factor Analysis) method considering Keiser Mayer Olkin (KMO) indicator, a score of over 0/6 and using Bartlett’s Test of Sphericity a value of (P.Value 0/001) was resulted. Under sub scales of A.Total ,B,C,D , from the stand point of percent of variance, indicates that the newly designed PG-SGA tool can predict up to 42 % outcome score. These subscales with a minimum coefficient value of 0/3 for Structural Validity of PG-SGA score is an indicator of good quality of consistency.