Purpose: Existing literature identifies the agency used by survivors of domestic violence when they participate in research. However, some human research ethics committees act as gatekeepers on research into survivors’ lived experience due to their perceived vulnerability. This article explores factors that influence survivors’ decision-making when they participate in research interviews. Methods: Sixteen survivors of intimate partner strangulation participated in interviews about their lived experience. The analysis of the interview transcripts was guided by the research question: What factors influence the agency that survivors of domestic violence draw on when making decisions about participating in research interviews? Results: The findings revealed four processes through which the self-efficacy of participants became apparent – cognitive, motivational, affective and selection processes. Self-efficacy underpins a person's agentic behaviours, particularly their decision-making. Conclusion: This article highlights how survivors of intimate partner strangulation, notwithstanding their lived experience of extreme violence, exercise self-efficacy. Knowledge in this area is valuable because it indicates survivors who have left the abusive relationship and have engaged in support can make informed decisions about their participation in research interviews. Such understandings can provide researchers with an increased awareness about the wellbeing of participants during interviews and human research ethics committees can be confident that research participants, who may be considered ‘vulnerable’, have the ability to assess their capacity to engage in research, if the caveats of having left the abusive relationship and having sought support are satisfied.