The reliability and validity of discrete and continuous measures of psychopathology: A quantitative review.

Abstract

In 2 meta-analyses involving 58 studies and 59,575 participants, we quantitatively summarized the relative reliability and validity of continuous (i.e., dimensional) and discrete (i.e., categorical) measures of psychopathology. Overall, results suggest an expected 15% increase in reliability and 37% increase in validity through adoption of a continuous over discrete measure of psychopathology alone. This increase occurs across all types of samples and forms of psychopathology, with little evidence for exceptions. For typical observed effect sizes, the increase in validity is sufficient to almost halve sample sizes necessary to achieve standard power levels. With important caveats, the current results, considered with previous research, provide sufficient empirical and theoretical basis to assume a priori that continuous measurement of psychopathology is more reliable and valid. Use of continuous measures in psychopathology assessment has widespread theoretical and practical benefits in research and clinical settings.

A paradigm shift in psychiatric classification: the Hierarchical Taxonomy Of Psychopathology (HiTOP)

“…Moreover, schizotypy as a latent construct (personality organization) is centrally embedded in a diathesis-stressor theoretical model that has considerable utility as an organizing framework for the study of schizophrenia, schizophrenia-related psychopathology (e.g., delusional disorder, psychosis not otherwise specified, schizotypal, paranoid and other related personality disorders) as well as putative schizophrenia endophenotypes, a view I have advocated for several decades [3][4][5][6] . Note, the term schizotypy is not restricted to describe only those clinical manifestations that are associated with schizotypal personality disorder 2,5,6 .…”

“…There are two reasons to expect that it will. First, dimensional phenotypes have been found to have greater reliability and stronger associations with validators than categorical diagnoses 4 , indicating that dimensional descriptions are more informative. Second, dimensions have been shown to be more useful in clinical research.…”

Are we witnessing the decline effect in the Type D personality literature? What can be learned?

“…Long-standing concerns about statistical and conceptual difficulties of categorical/typological constructs have been substantiated in recent work using sophisticated simulated comparison data techniques [29,30] that consistently favors dimensional conceptualizations. One systematic review [29] compared 377 articles with 311 distinct findings and concluded:…”

Experiencias esquizotípicas en la adolescencia: propiedades psicométricas del Schizotypal Personality Questionnarie-Child

“…Un formato de respuesta Likert mejora la fiabilidad de las puntuaciones y favorece la obtención de evidencias de validez (Lozano, García-Cueto, y Muñiz, 2008). Asimismo, una puntuación dimensional en psicopatología mejora sustancialmente la validez y la fiabilidad de la medición (Markon, Chmielewski y Miller, 2011).…”

“…Se debe mencionar que la posible mejora de la fiabilidad de las puntuaciones del SPQ-C podría venir determinada por el formato de respuesta tipo Likert de 5 puntos utilizada en este trabajo. En la literatura especializada se aconseja la utilizacion de este formato de respuesta para mejorar la calidad métrica de las puntuaciones (Lozano et al, 2008), así como para la construcción de puntuaciones dimensionales en medidas psicopatológicas (Markon et al, 2011). Por otro lado, ningún item presentó un funcionamiento diferencial en función del sexo de los participantes, aspecto que garantiza la comparación y la equidad de las puntuaciones entre los grupos a comparar.…”