Evaluating the impact of MeSH (Medical Subject Headings) terms on different types of searchers

•The usefulness of controlled vocabularies, exemplified by Medical Subject Headings (MeSH), was evaluated by a controlled user experiment.•MeSH terms were most useful for domain experts in terms of precision measure.•Domain knowledge was correlated with the precision score, whereas search training correlated with the recall score.•This study demonstrated the feasibility of re-using a test collection originally created for evaluating the effectiveness of retrieval techniques for a controlled user experiment.