4. DISCUSSION
This study demonstrated that Tr-PedsQL™ 3.0 EoE Module had good reliability and validity among teens and their parents with EoE. These findings are in line with previous research on the psychometric properties of the original version of the PedsQL™ EoE Module.7 In our country, there is currently no valid and reliable QoL scale related to EoE developed or adapted for children in Turkish. Although the linguistic validation and cultural adaptation of the PedsQL™ 3.0 EoE module have been published in Spanish, there have been no validity and reliability studies in any other languages found outside of our study.4
Franciosi et al. have developed a specific EoE scale to determine the disease-related quality of life in children with EoE, consisting of a patient version for different age groups in the pediatric population and a parent proxy version.7, 9, 21 They reported the reliability and validity of the PedsQL™ EoE Module in a USA pediatric EoE population. Their results showed that the module demonstrated good internal consistency, test-retest reliability, and construct validity, similar to the findings of the Tr-PedsQL™ 3.0 EoE Module.
Scales, originally designed in their original language, can only be applied to the populations they were designed for. Therefore, their use in a different context requires linguistic validation and cross-cultural adaptation to the country in which they will be applied, while maintaining the original meaning and intent of the items.
In the symptom I domain, our patients and their parents don’t understand ”heartburn” (item 2) because it does not have a single-word equivalent in Turkish. In Turkish, patients describe the sensation as ” Burning sensation behind the breastbone or bitter and sour secretion flowing back into their mouths,” which reminds the doctor of reflux, another symptom. The researchers resolved this issue by consulting experts and using a description that accurately conveyed the intended meaning in Turkish. This is a crucial step in ensuring that the translated version is comprehensible and relevant to the target population. Secondly, during the linguistic validation process, it became apparent that some items in the parent report version lacked verbs. This omission affected the clarity and comprehensibility of these items for parents. To address this issue, we added verbs to all the items that lacked them and then parents were able to answer without any issues. After making these adjustments, we did not encounter any issues with parents and teens during the cognitive interviews stage, demonstrating the effectiveness of the revisions in enhancing the scale’s usability.
Moderate agreements were found for Treatment, Worry, Communication, and Food feelings dimensions of Tr-PedsQL™ 3.0 EoE Module between teens and their parents. The study by Franciosi et al. (2013) also found moderate agreement only for symptom I and poor agreement for treatment and communication dimensions.7 The Treatment, Worry, Communication, and Food feelings dimensions of PedsQL™ 3.0 EoE Module are generally related to subjective experiences and individual perceptions.22
The construct validity of the Tr-PedsQL™ 3.0 EoE Module, as shown by significant correlations between its Symptoms Total, Symptoms I, and Symptoms II scores with the Tr-PEESS v2.0 scores, provides evidence of convergent validity. Convergent validity pertains to the degree to which two measures that are supposed to assess the same construct are indeed related to each other.23 Additionally, the absence or weak correlation between the Communication and Food Feeling dimensions, which are not present in the Tr-PEESS v2.0 but are included in the Tr-PedsQL™ 3.0 EoE Module, supports the divergent validity.
The lowest scores were obtained from the Food and Eating dimension, indicating that this dimension is the most problematic for both teens and their parents. These findings are consistent with previous studies7, 24, which have highlighted the impact of EoE on food-related activities and quality of life. In Warners et al. study24, the authors discussed the challenges faced by patients with EoE, particularly in terms of food avoidance and dietary restrictions, and how these factors contribute to decreased quality of life. Our results further emphasize the importance of addressing food-related issues in the management and treatment of EoE to improve patient outcomes and overall well-being.
There are some limitations in this study. It is performed in Turkish children at a single center which may limit the generalizability of the results. The number of participants in the study may seem limited, it should be noted that our center is a reference hospital for EoE in Turkey and has the highest number of cases. This study evaluates the validity and reliability of the Turkish version of the PedsQL™ 3.0 EoE Module. Therefore, we could not compare the our results with similar studies conducted in other languages. Due to the absence of a Turkish scale that assesses quality of life in EoE or a Turkish quality of life scale that is similar to dimensions in the PedsQL™ 3.0 EoE module, only the Tr-PEESS v2.0, which assesses symptoms, was used to test convergent validity.