Ana R. Delgado

Cognitive mediators and sex-related differences in mathematics

Abstract Sex-related differential studies on mathematical abilities have hardly taken into account the mediator role of the verbal factor, which contrasts with the interest shown in the mediator role of visuospatial aptitude. We predicted that if sex-related differences were found, mental rotation would mediate mathematical abilities typically favoring males (geometry and verbal problems) and lexical access would mediate the one favoring females (arithmetic). Data from 455 participants with a median age of 13 were analyzed, showing that sex-related effect sizes in mathematical criteria were small, ranging from d=−.16 to .18 (corrected by attenuation), as expected for unselected samples. Lexical access scores were consistent predictors for every mathematical subdomain, and mental rotation added to the prediction only for geometry and word problems.

Sex differences in visuospatial ability: Do performance factors play such an important role?

This study was designed to analyze some performance factors as a possible source of sex-related bias in psychometric tests of visuospatial aptitude. Goldstein, Haldane, and Mitchell (1990) explored the effect of two response styles—slowness of performance and reluctance to guess—by using a 3-D mental rotation test (the task showing the largest cognitive sex difference) and found that time limits and raw scores contributed substantially to the male advantage. We applied two tests in thespeed-power continuum to a representative sample of 621 males and 821 females in their last year of high school in a 2 × 2 (gender × time) full factorial design. Reluctance to guess was similar for males and females. Males obtained more correct responses on both tests, and for both time conditions, than did females. These results are not only statistically significant but also are of substantial practical consequence.

Further Evidence Favoring Three-Option Items in Multiple-Choice Tests

This study examined the validity of an item-writing rule concerning the optimal number of options in the design of multiple-choice test items. Although measurement textbooks typically recommend the use of four or five options - and most ability and achievement tests still follow this rule - theoretical papers as well as empirical research over a period of more than half a century reveal that three options may be more suitable for most ability and achievement test items. Previous results show that three-option items, compared with their four-option versions, tend to be slightly easier (i. e., with higher traditional difficulty indexes) without showing any decrease in discrimination. In this study, two versions (with four and three options) of 90 items comprising three computerized examinations were applied in successive years, showing the expected trend. In addition, there were no systematic changes in reliability for the tests, which adds to the evidence favoring the use of the three-option test item.

Scoring neuropsychological tests using the Rasch model: an illustrative example with the Rey-Osterrieth Complex Figure.

Parametric statistical methods are typically used for analyzing test scores, even though they are ordinal at best. The Meyers and Meyers’ Rey-Osterrieth Complex Figure four-category scoring system has been evaluated with the Rasch Rating Scale Model, and disordered thresholds have been found. However, Rasch-modeling dichotomized data led to good fit for both normal (n = 219) and Traumatic Brain Injury (n = 54) samples and generalized validity for these groups, as well as for male and female groups. The logarithmic transformation of the item and person data performed by the model converts the ordinal data to yield interval scaled data. This is desirable not only from a scientific perspective, but also from the point of view of interpretability and communicability.

The Effect of Instructions on Multiple-Choice Test Scores

Summary: Most standardized tests instruct subjects to guess under scoring procedures that do not correct for guessing or correct only for expected random guessing. Other scoring rules, such as offering a small reward for omissions or punishing errors by discounting more than expected from random guessing, have been proposed. This study was designed to test the effects of these four instruction/scoring conditions on performance indicators and on score reliability of multiple-choice tests. Some 240 participants were randomly assigned to four conditions differing in how much they discourage guessing. Subjects performed two psychometric computerized tests, which differed only in the instructions provided and the associated scoring procedure. For both tests, our hypotheses predicted (0) an increasing trend in omissions (showing that instructions were effective); (1) decreasing trends in wrong and right responses; (2) an increase in reliability estimates of both number right and scores. Predictions regarding pe...

The role of instructions in the variability of sex-related differences in multiple-choice tests

Abstract When both experts and lay people interpret data on sex-related differences, they usually forget that the instruments for data collection might be provoking such differences. This experiment, carried out on 240 participants, focused on the effects of four instruction/scoring conditions on sex effect size in two computerized tests — vocabulary and mental rotation, for which sex-related differences had been shown to be, respectively, small (favoring females) and large (favoring males). Given the caution which seems to characterize female performance, our general hypothesis predicted that, under instructions encouraging guessing, effect sizes favoring males would augment and effect sizes favoring females would diminish. The opposite results were expected under instructions discouraging guessing. Some supporting evidence was found.

Análisis Rasch de la versión española de la escala Mindful Attention Awareness Scale en una muestra clínica

INTRODUCTION The clinical use of mindfulness has increased recently, and the Mindful Attention Awareness Scale (MAAS) has become one of the most used tools to measure it. The aim of this study was to test the effectiveness of mindfulness training and analyzing the psychometric properties of the MAAS scores in a clinical sample using the Rasch Model. METHODS One hundred and ninety-nine participants with mood-anxiety clinical symptoms were recruited. The experimental group (n=103) received mindfulness training, and the control group (n=96) a conventional outpatient treatment for the same duration. The pre-post MAAS scores were analyzed to test the effectiveness of training, the psychometric properties of the scores, and differential item functioning (DIF) using the Rating Scale Model (RSM). RESULTS Misfit in items 9 and 12, DIF in item 9, and Spanish translation problems in the items 5, 9 and 12 were observed. The repetition of the analysis without these items was decided. Appropriate dimensionality, fit and reliability values were obtained with the short version, MAAS-12. CONCLUSIONS Contrary to previous studies, the MAAS was sensitive to treatment-associated change. However, the commonly used MAAS has some translation and metric problems, and should be revised. MAAS-12 is a better scale than MAAS but suffers from construct under-representation. Constructing tools from a coherent theoretical perspective is suggested, so that all mindfulness facets are represented.

Funcionamiento diferencial de los ítems del test Mini-mental en función de la patología

INTRODUCTION Comparing the height of males and females would be impossible if the measuring device did not have the same properties for both populations. In a similar way, the cognitive level of diverse groups of patients should not be compared if the test has different measurement properties for these groups. Lack of Differential Item Functioning (DIF) is a condition for measurement invariance between populations. MATERIAL AND METHODS The most internationally used screening test for dementia, the MMSE (or Mini-mental State Examination), has been analysed using an advanced psychometric technique, the Rasch Model. The objective was to determine the invariance of mini-mental measurements from diverse groups: Parkinsons disease patients, Alzheimers type dementia and normal subjects. The hypothesis was that the scores would not show DIF against any of these groups. The total sample was composed of 400 subjects. RESULTS Significant differences between groups were found. However, the quantitative comparison only makes sense if no evidence against measurement invariance was found: given the kind of items showing DIF against Parkinsons disease patients, the MMSE seems to underestimate the cognitive level of these patients. CONCLUSIONS Despite the extended use of this test, 11 items out of 30 show DIF and consequently score comparisons between groups are not justified.

Validity Study of the Beck Anxiety Inventory (Portuguese version) by the Rasch Rating Scale Model

Our objective was to conduct a validation study of the Portuguese version of the Beck Anxiety Inventory (BAI) by means of the Rasch Rating Scale Model, and then compare it with the most used scales of anxiety in Portugal. The sample consisted of 1,160 adults (427 men and 733 women), aged 18-82 years old (M=33.39; SD=11.85). Instruments were Beck Anxiety Inventory, State-Trait Anxiety Inventory and Zung Self-Rating Anxiety Scale. It was found that Beck Anxiety Inventorys system of four categories, the data-model fit, and people reliability were adequate. The measure can be considered as unidimensional. Gender and age-related differences were not a threat to the validity. BAI correlated significantly with other anxiety measures. In conclusion, BAI shows good psychometric quality.

Order in Spanish colour words: Evidence against linguistic relativity

The hypothesis that the Berlin and Kay (1969) colour sequence would be replicated in Spanish colour-word usage has been corroborated on 131,028 colour words from a representative corpus (N = 188,975,000). The observed sequence of white, black, red, green, blue, yellow, grey and brown is highly consistent diachronically (through current and contemporary Spanish), synchronically (through various countries) and with the expected order. Considering the divergence of Spanish vocabularies among geographical areas in the last centuries, the almost total agreement did not have a high prior probability under hypotheses of culturally arbitrary colour vocabularies. It is difficult to see how linguistic relativity could adequately account for such a robust result. The use of ordinal statistics and non-reactive measures to study cultural products constrained by epigenetic rules, such as colour vocabularies, is presented as an exercise of methodological consilience.