<qa>  What is the name of the study approved by the Central Denmark Committee on Biomedical and ResearchEthical considerations: The study is approved by the Central Denmark Committee on Biomedical and Research Ethics and the Danish Data Agency. Transport costs in connection with control visits are refunded and it is attempted that examinations take place at days where the patient has to meet for a control visit at the hospital. At present, the treatment offer to this patient group does not include pre- and post-operative optimisation and it is not deemed unethical to randomise patients to pre- or post-operative optimisation or standard treatment, respectively. The study is registered in the American clinical database 