Test-Retest Reliability, Responsiveness and Interpretability of CLEFT-Q

The goal of this observational study is to test the questionnaire CLEFT-Q in a population of patients with cleft lip and/or palate. The main questions it aims to answer are:

1. Are CLEFT-Q scores reliable over time? 2. Can CLEFT-Q detect change following surgical treatment intervention? 3. What is the norm for CLEFT-Q within a control population who do not have cleft lip and/or palate? 4. What is the Minimal Clinically Important Change of CLEFT-Q in different subpopulations of cleft lip and/or palate? 5. Do changes in CLEFT-Q scores correlate with changes in objective outcomes following a surgical intervention? 6. What are the main expectations that patients express before a surgical intervention? 7. How do patients perceive that the results after surgical interventions meet their expectations? 8. Do patients express concepts of importance postoperatively that are not examined by CLEFT-Q? 9. How do healthcare professionals perceive that the use of CLEFT-Q affects clinical decisions and processes?

Participants will

1. Fill out the questionnaire CLEFT-Q twice with a two-week space. 2. Before and 1 year after an operation. 3. Be interviewed about their experiences related to an operation or using CLEFT-Q.

Researchers will compare results from the cleft lip and palate population to see if there is a difference between them and a population without cleft lip and palate.