Towards a core outcome set for hemorrhoidal disease—a systematic review of outcomes reported in literature

PURPOSE: Previously published literature regarding treatment of hemorrhoidal disease (HD) revealed a lack of uniform defined outcomes. These differences between outcomes among studies limit transparency and lead to incomparability of results. The aim of this study was to systematically list the types of outcomes used in HD studies. This list will be used to develop a core outcome set. METHODS: We searched Medline (Pubmed), Embase (OVID), and Cochrane for interventional studies for adult patients with HD. Two authors independently identified and reviewed eligible studies. This resulted in a list of outcomes reported by each clinical trial. All outcomes were categorized using the conceptual framework OMERACT filter 2.0. RESULTS: A total of 34 randomized controlled trials and prospective observational studies were included in this study. A total of 59 different types of outcomes were identified. On average, 5.8 different outcomes (range 2–8) were used per study. The outcomes were structured into three core areas and10 ten domains. The most commonly reported core area was pathophysiological manifestations including the domain symptoms, complications, and recurrence. The most frequently reported outcomes were pain (91%), blood loss (94%), prolapse (71%), and incontinence (56%). There was a high variation in definitions of the common outcomes. And often there was no definition at all. CONCLUSION: This study shows a substantial heterogeneity in the types of outcomes in HD studies. We provided an overview of the types of outcomes reported in HD studies and identified a list of potentially relevant outcomes required for the development of a COS. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00384-018-3046-2) contains supplementary material, which is available to authorized users.