Can health services defeat epidemiology? This question is not inspired by the School of Public Health summer softball league. Instead, it’s inspired by a conversation with my colleague Ed Boudreaux about screening for suicidal ideation as a tool for preventing suicide attempts and suicide deaths.
Ed wondered whether providers’ or health systems’ responses to screening questionnaires could make those questionnaires appear less accurate. Clinicians are expected to respond to suicidal ideation with more detailed risk assessment, safety planning, and appropriate follow-up care. If those interventions are effective, then risk of subsequent suicide attempt or suicide death will be reduced. And the expected association between suicidal ideation and subsequent suicidal behavior will be weakened. And we might falsely conclude that screening tools are inaccurate.
My first response to Ed was, “We should be so lucky!” The relationship between suicidal ideation and subsequent suicidal behavior is very strong. Unfortunately, our interventions to reduce risk of suicidal behavior are not that strong. We certainly hope to make a dent in the strong relationship between suicidal ideation and subsequent suicide attempt or suicide death. But that would be just a dent.
But Ed’s point is an important one. In fact, it’s central to our recently-funded MHRN project to evaluate implementation of Zero Suicide implementation across health systems – led by Brian Ahmedani at Henry Ford Health System. Following the Zero Suicide scheme, we expect our health systems to implement reliable programs to identify suicide risk, engage people at risk, deliver effective interventions, and assure appropriate care transitions. Our hypothesis is that effective implementation will weaken the association between suicidal ideation (or some other indicator of risk) and subsequent suicidal behavior. Our metrics for evaluating the impact of Zero Suicide programs will look for changes in those relationships over time. For example: Is the relationship between response to PHQ9 item 9 and risk of subsequent suicide attempt weaker after implementation of systematic risk assessment and safety planning?
Ultimately, this is a “problem” we should embrace. Our epidemiologic research identifies priority areas for improving health services. In response, our health systems implement new care processes. And those improvements undermine the findings of our epidemiologic research.
If our previous findings cannot be replicated, that may be good news. Several of us have been involved in over twenty years of research to improve management of depression in primary care. For much of that time, we had no difficulty replicating our findings regarding high rates of treatment discontinuation and low rates of treatment success. That’s not a history to be proud of.