Methods
This is a cross-sectional single center study conducted at Marmara University Medical Faculty, Division of Pediatric Pulmonology Selim Çöremen CF Center between May 2019 and July 2019.
Participants were asked to complete the PHQ-9 and GAD-7 questionnaires to evaluate the level of their depression and anxiety at the outpatient clinic during routine follow-up visit. Patients with a definitive diagnosis of CF were eligible. Consecutive sampling method was used and all patients who came to the outpatient clinic during the study period were involved into the study.
The objectives of this study are to measure depression and anxiety levels of patients and their caregivers and to determine the risk factors affecting these levels. Patients’ signs and symptoms were noted before the questionnaires were done. Necessary information for evaluation of the clinical status of the patient and adherence to medical treatment/airway clearance were collected from medical records. Adherence was assessed by patient/parent self-reports. Patients’ age, age at the time of diagnosis, anthropometric measurements, mutations, forced expiratory volume in one second (FEV1) %, treatment and pulmonary physiotherapy regimens, past medical history (allergic bronchopulmonary aspergillosis, pneumothorax, hemoptysis, number of hospital admissions and exacerbations, sputum colonization history) and co-morbidities were noted for analysis. CF disease severity was classified as mild if the FEV1 was more than 70%, as moderate if the FEV1 was between 40% and 69.9%, and as severe if the FEV1 was 39.9% or below of the predicted value.
For the assessment of anxiety and depression, participants were asked to complete the validated Turkish versions of 9-item Patient Health Questionnaire Depression Scale (PHQ-9) and 7-Item Generalized Anxiety Disorder Scale (GAD-7)10. The PHQ-9 is composed of nine depressive symptom items listed in the Diagnostic and Statistical Manual of Mental Disorders-4th edition (DSMIV) for depression. Patients were asked to rate the extent of their symptoms that had bothered them during the previous 2 weeks using a 4-point Likert rating scale. The PHQ-9 severity score ranges from 0 to 27. Patients achieving a score equal or above 15 are regarded as suffering from at least minor depression 11.The GAD-7 is a tool to assess general anxiety disorder and it is comprised of seven items representing the DSM-IV symptom criteria for GAD (e.g., “Feeling nervous, anxious or on edge”).
Patients were asked to indicate how often, during the last 2 weeks, they were bothered by each symptom, using a 4-point Likert-type rating scale. Total test scores range from zero to 21 with a score of eight deemed sufficient to identify symptoms of general anxiety disorder, panic disorder, post-traumatic stress disorder or social anxiety disorder12. The internal consistency reliability of the Turkish version of the GAD-7 (Cronbach’s α = 0.85) and the test–retest reliability (intraclass correlation = 0.83) were reported to be good12; 13.
The aim of the study was explained and informed consent was obtained from the participants beforehand. The Marmara University Medical Faculty Research Ethics Committee had approved the study, protocol number 09.2020.510.

Statistical analysis

Data were analyzed using the Statistical Program for Social Sciences (SPSS for IBM, 21.0). Descriptive statistics are presented in numbers, mean and standard deviations. The normal distribution of continuous variables was evaluated using the Shapiro‐Wilk test. The Mann–Whitney U test was used for group comparison and the Spearman’s rho correlation coefficient to assess relationships. p < 0.05 was used for statistical significance.