Mental illness among relatives of successful academics: implications for psychopathology‐creativity research

World Psychiatry 18:3 October 2019 Another illustrative example is the fact that authors themselves disagree on the ultimate aim of transdiagnostic research. Some of them claim that transdiagnostic research is a fundamental pathway to clinical utility for improving psychiatric classification and diagnosis, while others argue that the transdiagnostic approach does not primarily target the improvement of psychiatric classifi cation and diagnosis, but rather tests a general theory of psycho pathology. A further example is the fact that, until the publication of this systematic review, the empirical limitations and reporting quality of transdiagnostic research remained unaddressed: appraising and acknowledging the specific limitations of a certain domain of knowledge is equally, if not more, important as celebrating its successes. It may well be that some versions of a transdiagnostic approach are going to be necessary to improve psychiatric classification and care. What is certain is that, until studies continue to loosely and incoherently self-proclaim transdiagnostic without acknowledging any diagnostic information, it is unlikely that transdiagnostic research will bear any real-world meaning for clinicians, patients, and medical practice. Similarly, poor reporting on the number and type of (trans)diagnostic spectra prevents the appraisal, refinement, and eventual integration of categorical and dimensional approaches in psychiatric classification. The systematic review acknowledged that transdiagnostic categorical approaches that respect dimensionality are possible in organic medicine as well as in psychiatry, but this requires transparent reporting of the results. For example, the largest transdiagnostic study published to date demonstrated that it is possible to report the diagnostic information for almost all ICD-10 mental disorders. Furthermore, while it is possible that transdiagnostic interventions may display superior efficiency, cost-effectiveness, accessibility, and patient-reported satisfaction compared to specific-diagnostic interventions, demonstrating this would require robust comparative analyses specifically conducted to test the non-inferiority or superiority of the transdiagnostic approach. These analyses are infrequent in the current literature. The systematic review leveraged these caveats to put forward six empirical transdiagnostic research recommendations: TRANSD. The TRANSD recommendations are pragmatic and focus on improving the quality of appraising and reporting transdiagnostic constructs. Importantly, they do not provide any a priori restrictive definition of the transdiagnostic schemata; as such, they can be applied to different topics and stimulate critical research in the field. The first recommendation is to have a transparent definition of the gold standard (ICD, DSM, other), including specific diagnostic types, official codes, primary vs. secondary diagnoses, and diagnostic assessment interviews. Second, the primary outcome of the study, the study design, and the definition of the transdiagnostic construct should be reported in the abstract and main text. Third, the conceptual framework of the transdiagnostic approach – across-diagnoses (comparing different ICD/ DSM categorical diagnoses against each other), beyond-diagnoses (employing ICD/DSM diagnostic information to go beyond it, testing new diagnostic constructs such as biotypes), other (with an explanation of the conceptual framework) – should be appraised. Fourth, the diagnostic categories, diagnostic spectra, and non-clinical samples in which the transdiagnostic construct is being tested and then validated should be indicated. Fifth, the degree of improvement of the transdiagnostic approach should be shown against the specific diagnostic approach through spe cific comparative analyses. Sixth, the generalizability of the trans diagnostic construct should be demonstrated through external validation studies. It is hoped that these recommendations will improve the transparency and consistency of the next generation of transdiagnostic research, overcoming the current limitations of knowledge and benefitting psychiatric care.