Letter to the Editor Regarding ‘Levodopa Intestinal Gel Infusion Therapies in Advanced Parkinson's Disease: A Swedish Study on Real-World Use and Costs’

or levodopa-entacapone-carbidopa intestinal gel (LECIG).On the basis of analysis of these data, the authors concluded that cassette use, annual per patient costs, and treatment discontinuation rates were higher for patients with advanced PD in Sweden treated with LECIG when compared with patients treated with LCIG.We believe there are some shortcomings in the methodology used to make these comparisons which may have resulted in some erroneous conclusions being drawn. Patient Subgroup Definition and Cost AnalysesThe definition of treatment cohorts and patient subgrouping for analysis is key to interpretation of the cost comparison data and warrants further scrutiny.For reasons best known to the authors, in this analysis patients were categorised into subgroups based on their previous exposure to levodopa pump-based therapies: pump nave (no previous levodopa pump treatment, PTN) or pump-experienced (prior levodopa pump treatment used at any time point, including reinitiation of the same pump treatment, PTE).These PTN and PTE categories are complex, overlapping, and hard to interpret, but seem to underlie the interpretation of the data in this study.As we understand it, according to the specified categorisation, a 'pump nave' patient