Quality of life assessment

The Turkish version “KINDL” questionnaire was used to assess changes in quality of life over the course of the trial, as was previously done (https://www.kindl.org/english/language-versions/turkish/)⁵⁷. The questionnaire consists of 24 Likert-scaled items grouped into 6 subscales measuring specific aspects of quality of life (QoL), including physical well-being, emotional well-being, self-esteem, family, friends, and school. An additional “Disease” module for patient’s self-identifying as hospitalized or having a long-term illness was used. The presence of the symptom is evaluated based on a quintile Likert scale; “never,” “rarely,” “sometimes,” “frequently,” and “always” options are scored by “1,” “2,” “3,” “4,” and “5”, respectively. Subscale scores are produced by combining the item ratings for each of the 6 subscales and converting each subscale score to a scale of 0–100, with higher scores representing better QoL. Similarly, a total score is produced by combining the item ratings across all 6 subscales (not including the Disease module). The SPSS syntax files provided by the KİNDL-R site were used to enter and analyze the KINDLR data using IBM SPSS Statistics trial version software package for MAC OS. The KINDL parent form was used for 8 to 16-year-old children.