A new meta-analysis led by McMaster University challenges the reliability of standardized diagnostic interviews used in mental health assessments. Published in JAMA Network Open, the study analyzed 57 studies involving over 8,000 adults across 26 countries, revealing that these interviews are only moderately consistent. In some cases, individuals received different diagnoses when assessed just days apart. The findings indicate that diagnostic interviews are more reliable for substance use disorders than for conditions like anxiety and depression, which are subjective and influenced by personal experiences. Senior author Laura Duncan emphasizes that the inconsistency in diagnoses can lead to inappropriate treatments and highlights the necessity for improved diagnostic methods. The study suggests that mental health professionals should not treat these interviews as the definitive assessment tool but rather combine them with clinical insights to enhance diagnostic accuracy.