Rethinking Benefits in Health Research, Reflections of an Ethics Committee.

The principle of beneficence in health research implies the effort of researchers to minimize risk to participants and maximize benefits to participants and society, which could be considered an abstract definition. Therefore, the benefits are not easily conceived by researchers who fail to achieve their goal, which is to privilege the well-being of participants. The purpose of this work was to describe and discuss the theoretical elements that support the principle of beneficence so that their knowledge allows designing and granting adequate benefits to participants. The present document defines the principle of beneficence. It also analyzes the maximization of benefits, the distinctions between different classifications of benefits, and the differentiation from compensations or incentives. With all this information, researchers must do a critical deliberation to select adequate benefits for participants of their studies, considering the type of study, potential participants, probability of risk, among others. These benefits should not be understood as a charity that researchers grant to the participant; they should be conceived as any form of action in favor of the well-being of participants. Participants must always be considered as moral agents, responsible for deciding whether the benefits would outweigh the possible negative unintended consequences of a particular study. Finally, no risk should be taken if it is not commensurate or proportional to the benefit of the research study.

After a disaster: Validation of PTSD checklist for DSM-5 and the four- and eight-item abbreviated versions in mental health service users.

Posttraumatic stress disorder (PTSD) is a common and disabling condition developing in one of four survivors after an earthquake. Brief and self-reported validated measures for assessing PTSD symptom severity are necessary to improve care access and assess disorder progress and treatment response. Therefore, we evaluated the psychometric properties of the PTSD-Checklist for the DSM-5 (PCL-5) of 20-, 8- and 4-item in patients that sought specialized mental health services after a catastrophic earthquake that stroke Mexico on September 19th, 2017. The internal consistency of 20-, 8- and 4-item PCL-5 was adequate (≥.7). Using the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) as a reference, signal detection analyses revealed a PCL-5 score of 27 as optimal (sensitivity = .96, specificity = .73) for identifying probable PTSD cases. The shortened versions highly correlated with the full PCL-5 and had comparable diagnostic utility. Our results indicate that the 20-item PCL-5 and the abridged versions can effectively identify possible PTSD cases. The 8-item version has better psychometric properties and more consistent diagnostic utility across time and civil populations. These measures must be evaluated in independent samples to corroborate their utility in different populations and regarding diverse traumatic events.

Estudio de la variabilidad genética del DRD4 y del DAT1 en individuos habitantes de la Ciudad de México / Genetic variability study of DRD4 and DAT1 in the urban population of Mexico City

Family, twin and adoption studies suggest that genetics plays an important role in the etiology of many psychiatric disorders. It has been proposed that the dopaminergic brain system could be affected in schizophrenia, substance abuse and attention deficit hyperactivity disorder. The most studied genes are two VNTR polymorphic systems; one located in the exon 3 of the dopamine D4 receptor (DRD4) gene, and the other in the 3' untranslated region of the dopamine transporter (DAT1 or SCLA6A3) gene. It has been reported that allele frequencies of these polymorphisms varied between populations and this could affect the results in the association studies. Due to the previous findings, the objective of the present study was to determine the allele frequencies of DRD4 and DAT1 in an epidemiological sample of the adolescent population of México City. We found that the frequencies presented in our study were in between those reported for Caucasians and those reported for the American Indigenous population, this result are consistent with Euro-Indigenous inbreeding that has occurred in Mexico. Moreover, the results presented in the present study could explain the lack of consistency in the association analysis and make necessary to develop these investigations in our population.

Existe evidencia fehaciente de la influencia genética en los trastornos psiquiátricos y se ha propuesto que el sistema dopáminergico cerebral puede ser uno de los afectados en diversos trastornos como la esquizofrenia, el abuso de sustancias y el trastorno por déficit de atención e hiperactividad. En este sentido, los sistemas genéticos más estudiados son 2 VNTRs; uno localizado en el exón 3 del gen del Receptor a dopamina D4 (DRD4) y el otro en la región 3' no traducida del transportador a dopamina (DAT1 o SCL6A3). Se ha reportado que las frecuencias alélicas de estos polimorfismos difieren significativamente entre poblaciones y que esto puede afectar los resultados en los estudios de asociación. Debido a lo anterior, el objetivo del presente trabajo fue determinar las frecuencias alélicas del DRD4 y del DAT1 a partir de una muestra epidemiológica de la población adolescente de la Ciudad de México. Las frecuencias alélicas reportadas en el presente estudio son intermedias a las reportadas en caucásicos y poblaciones indígenas de América, lo que concuerda con la historia de mestizaje ocurrida en México. Estás diferencias pueden ayudar a explicar la falta de consistencia en diferentes estudios de asociación y hacen necesario realizarlos en población mexicana.