The authors derive a general equation to compute multiple cut-offs on a total test score in order to classify individuals into more than two ordinal categories. The equation is derived from the multinomial logistic regression (MLR) model, which is an extension of the binary logistic regression (BLR) model to accommodate polytomous outcome variables. From this analytical procedure, cut-off scores are established at the test score (the predictor variable) at which an individual is as likely to be in category j as in category j+1 of an ordinal outcome variable. The application of the complete procedure is illustrated by an example with data from an actual study on eating disorders. In this example, two cut-off scores on the Eating Attitudes Test (EAT-26) scores are obtained in order to classify individuals into three ordinal categories: asymptomatic, symptomatic and eating disorder. Diagnoses were made from the responses to a self-report (Q-EDD) that operationalises DSM-IV criteria for eating disorders. Alternatives to the MLR model to set multiple cut-off scores are discussed.

From the very outset of scientific Psychology, psychologists have shown interest for drugs and their effects on behavior. This has given rise to numerous contributions, mostly in the form of Psychopharmacology publications. The aim of this study was to quantitatively evaluate these contributions and compare them with other academic disciplines related to Psychopharmacology. Using the PubMed database, we retrieved information about articles from 15 journals included in the Pharmacology and Pharmacy category of the Journal Citation Reports database for a 21-year period (1987 to 2007). There were 37540 articles which about 52% were represented by 3 journals. About 70% of psychology publications were represented by 2 of these journals. Psychology departments accounted for the 11% of the published papers, which places Psychology third behind Psychiatry and Pharmacology, which contributed to 22.69 and 13% respectively. Psychology contributed to the greatest number of studies in 3 journals, second in 3 and third in 8. This report represents the first effort to explore the contribution of academic Psychology to the multidisciplinary science of psychopharmacology. Although leaders of production of psychopharmacology research were from Psychiatry and Pharmacology, Psychology departments are an important source of studies and thus of knowledge in the field of Psychopharmacology