OBJECTIVES: Participants in oncology randomised controlled trials (RCT) are often permitted to switch from their randomised treatments onto alternative treatments. Intention-to-treat (ITT) assessments are prone to bias in the presence of switching and consequently the overall survival (OS) benefit and cost-effectiveness of the novel treatment may be underestimated. Regardless, decision-makers frequently reject statistical analyses which adjust for treatment switching in health technology assessment, often due to poor justification of methodological assumptions. This study applies adjustment methods to an RCT comparing dabrafenib to dacarbazine in patients with BRAF V600E/K mutation-positive metastatic melanoma, and investigates which adjustment method best fits this specific case study.  METHODS: The adjustment methods applied included the Rank Preserving Structural Failure Time Model (RPSFTM), Inverse Probability of Censoring Weights (IPCW), and two-stage adjustment. The suitability of each method was assessed by investigating their assumptions and trial characteristics. RESULTS: CONCLUSIONS: Adjusting for switching showed an increased OS effect for dabrafenib. Methodological assumptions must be rigorously investigated to demonstrate whether and which adjustment methods are justified.