Abstract. Background: This feasibility study of text-miningbased scoring algorithm provides an objective comparison of structured reports (SR) and conventional free-text reports (cFTR) by means of guidelineStructured reporting (SR) represents a new direction in communicating radiological reports to clinicians in a way that is clear and uniform (1). However, follow-up studies on SR have shown mixed results regarding adaptation and adherence (2-4). In particular, neuroradiological residents most commonly complain that SRs are overly constraining and time-consuming (5). In spite of that, there is an increasing tendency to use online solutions to generate SR templates (6). For instance, "CT brain" and "MR brain" were the third and fifth most frequently viewed SR templates in the Radiological Society of North America (RSNA) online library (7). SR templates can serve as core frameworks, but because of heterogeneous representations of diseases and co-morbidities, there is a substantial need to allow for customization of each report -primarily in the form of additional free text. Consequently, the distinction between conventional free-text (narrative) reports (cFTR) and SR becomes even more blurred, which makes their objective comparison even harder. This raises two further questions: Are SRs indeed 'better' than cFTRs? How can cFTRs be compared with SRs in an objective, fast and scalable way if SRs are often a mixture of structured and free (narrative) text?Firstly, there is a need to define how to objectively quantify 'better'. Commonly the method of choice for such quality assessments is either an expert opinion-based rating (5, 8) or a survey-based evaluation by physicians (4). Although both methods provide valuable insight, they are very laborious and time-consuming for experts and do not scale well for large datasets (4,8). Therefore, we aimed to implement an approach using the adherence to imaging and clinical guidelines as a quality measure.Secondly, in order to objectively compare cFTR with SR, we suggest an evaluation based on widely used text-mining technique using the 'bag of words' representation and cosine similarity (9, 10). The cosine similarity provides the core of many information retrieval systems (11,12). Reports can be 843 This article is freely accessible online.