This corpus-based contrastive study examines the thematic use of the semantic field of research and researchers in the Discussion section of biomedical reports in Spanish native texts and English-Spanish translations. This semantic field was divided into integral reference (specific named researchers), general nouns for researchers, and singular and plural nouns referring to research. Themes containing these lexical items were examined with regard to their syntactic manifestations and their lexicogrammatical relations with the main finite verb. Quantitative analysis was used to establish reference values for the native texts and to reveal differences between the two subcorpora. Qualitative contextual analysis then investigated how the data might be applied to the translated texts. The quantitative study showed that the Spanish texts had more integral references and more general researcher nouns in their themes whereas the translations had more singular research nouns, especially those referring to the current study. Singular research nouns were associated with more prepositional adjuncts in the Spanish texts but with more subject themes, either as head or as modifier, in the translations. The distribution of tenses was different in all categories except for plural research nouns, with a higher percentage of present and present perfect in the Spanish texts and more past indefinite in the translations. Differences were also found in the distribution of lexical verbs related to integral references and singular research nouns. The contextual analysis revealed that awareness of these differences and strategic choices based on them could lead to thematic and discourse patterns that come closer to the target-language norms for this genre.