Abstract
While the Interpersonal Psychological Theory of Suicide (IPTS) offers the potential to inform effective prevention strategies, previous evaluations of the model have been critiqued for only testing specific components of the theory. Additional arguments have also been made about whether the role of hopelessness should be tested using measures of interpersonal hopelessness or general hopelessness. We explicitly tested the full model of the IPTS using measures of both interpersonal hopelessness and general hope-lessness. Undergraduate students (n = 394) completed online measures related to the core tenets of the theory. Results indicated that the four-way interaction of burdensomeness, belonging, fearless-ness about death, and hopelessness was associated with a greater risk of suicide for both measures of hopelessness. Overall, our findings suggest that interpersonal hopelessness should be considered alongside other factors posited by the IPTS when understanding suicide risk in undergraduate students in Aotearoa New Zealand.