Scientific writing especially doctoral dissertation writing commands a high level of objectivity, room for new knowledge, and involvement of the reader. This is manifested in the way the writers demonstrate commitment and detachment to the claims they make and how they position writer-reader relations. Commitment and detachment in a writer’s claims are linguistically shown by the use of interactional metadiscoursal markers. Interactional metadiscourse markers are, therefore, important metadiscursive resources for writers to mark their epistemic stance and position writer-reader relations. To effectively achieve this, doctoral thesis writers need to use interactional markers appropriately and proportionately. Using a descriptive analytic design and following Hyland’s (2005) taxonomy and Kondowe’s (2014) categorization, this study investigated how doctoral students at JOOUST use interactional markers in their doctoral thesis writing. The paper analysed the extent, form, and function of interactional markers in the introduction and discussion sections of doctoral theses deposited at JOOUST library across all disciplines. The results showed that the use of interactional markers in doctoral thesis writing among JOOUST students was skewed. Boosting appears recurrently compared to hedging, with the other interactional markers being used minimally. Boosters were used to persuade readers of the validity of claims. Hedges were used to persuade readers of the detachment from the claims made. These findings suggest the need for awareness raising on the usefulness of hedging and boosting devices in moderating the claims made in thesis writing because research theses are academic documents that must adhere strictly to impersonal and formal writing conventions.