A recent study has cast a shadow over the reliability of mental health diagnostic interviews, revealing significant variability in their effectiveness across different conditions. Commonly relied upon in clinical settings and research, these interviews, which are pivotal for diagnosing mental disorders such as depression, anxiety, and substance use disorders, are increasingly viewed as falling short of their touted ‘gold standard’ status.
Mixed Findings on Diagnostic Interviews
Conducted by Laura Duncan, a psychiatry professor at McMaster University in Ontario, Canada, the study published in JAMA Network Open synthesises evidence from a range of tests assessing the reliability of diagnostic interviews between February 2024 and September 2025. While these interviews are frequently seen as the primary method for diagnosing mental health issues, Duncan highlights that their validity and reliability are not as robust as previously believed.
Duncan remarked, “These interviews are often treated as a ‘gold standard’ for assessing mental disorders, but they lack a definitive benchmark that demonstrates excellent validity and reliability.” Despite longstanding debates surrounding their reliability, there remains a lack of alternative methods, which may explain why diagnostic interviews continue to dominate the field.
Reliability Varies by Condition
The study employed Cohen’s kappa coefficient to measure the consistency of diagnoses across various mental health conditions. The results revealed that while the average reliability was generally more favourable for substance use disorders, the highest reliability was associated with opioid use disorder. This disparity can be attributed to the nature of substance use disorder criteria, which are primarily behavioural in nature. Duncan notes, “It’s often easier to estimate how many drinks you had in a week than the number of days you felt sad or anxious.”
Dr Michael First, a psychiatrist at Columbia University and co-author of the Structured Clinical Interview for DSM-5 (SCID), expressed frustration with the study’s limitations. He acknowledged the variability in diagnostic interviews but called for more granular information to delineate which specific instruments exhibit greater reliability. “It’d be nice to be able to look at this and say: ‘Oh, based upon this paper, I should pick this one because of this,’” First commented. “But there’s simply not enough information here.”
The Need for More Rigorous Standards
The study’s authors reviewed various diagnostic tools, including the SCID and the Mini International Neuropsychiatric Interview (Mini), as well as more targeted instruments like the Clinically Administered PTSD Scale (CAPS). First pointed out a critical flaw in the study’s methodology, which grouped fully structured interviews with semi-structured ones. Fully structured interviews, he noted, yield more consistent results because they adhere strictly to a scripted format. This rigidity can sometimes hinder the diagnostic process, failing to account for the nuances of individual patient responses.
In contrast, semi-structured interviews allow clinicians to adapt their questioning based on the patient’s responses, potentially leading to a more accurate diagnosis, albeit with increased variability in results. Duncan acknowledged the need to address First’s concerns but lamented the lack of sufficient data to make definitive comparisons between different interview types.
A Call for Future Approaches
Despite the limitations of current diagnostic tools, First remains hopeful for advancements in psychiatric evaluation. For decades, the field has anticipated the introduction of more objective laboratory tests for mental health conditions. “We’ve been saying that for 50 years,” he remarked.
Duncan advocates for a shift away from rigid diagnostic categories, suggesting that conditions should be viewed on a spectrum. This approach could foster a deeper understanding of mental health and promote more tailored treatment strategies.
Why it Matters
As mental health awareness continues to grow, the implications of this study are profound. The effectiveness of diagnostic interviews is critical not only for individual treatment but also for shaping broader public health policies. A more nuanced understanding of mental health assessment could ultimately lead to better outcomes for patients, fostering a healthcare environment that prioritises accuracy and compassion in diagnosis and treatment.
