F.J.R. van de Vijver

Assessment of cognitive deterioration in individual patients following cardiac surgery: Correcting for measurement error and practice effects

Assessment of cognitive change in individual patients may be confounded by unreliability of test scores and effects of repeated testing. An index correcting for both problems is proposed and compared with change indices that do not or do not adequately deal with measurement error and practice effects. These indices were used to examine cognitive deterioration in a sample of 63 patients undergoing cardiac surgery. It was demonstrated that for test measures with a low reliability, failure to correct for measurement error resulted in overestimation of deterioration rates. For test measures with a high reliability, but showing substantial practice effects, failure to correct for practice effects resulted in underestimation of deterioration rates. With the proposed index, cognitive deterioration shortly after cardiac surgery was most frequently observed for attention and psychomotor speed, less frequently for verbal fluency, and only occasionally for learning and memory.

Cross-Cultural Research Methods in Psychology: Equivalence and Bias: A Review of Concepts, Models, and Data Analytic Procedures

Introduction This chapter addresses the methodological issues associated with equivalence and bias in cross-cultural research. These issues are a consequence of the nonexperimental nature of the research designs of cross-cultural studies. True experiments are based on the random assignment of participants to different experimental conditions, which presumably ensures that confounding variables are equated across experimental conditions. However, participants cannot be randomly assigned to cultures, and groups that are compared in cross-cultural studies can hardly ever be seen as matched on all background variables that are relevant for the constructs of interest. Cross-cultural psychology is not unique in the impossibility of matching groups; many studies in clinical and educational psychology involve situations in which intact groups are studied, and the assumption of the similarity of background characteristics across groups is unrealistic. The inability to conduct true experiments to address essential questions in cross-cultural psychology implies that we have to be careful in conducting our studies, being cognizant of relevant methodological knowledge and tools. It also implies that cross-cultural studies are always threatened by bias and inequivalence when cultural groups are being compared. This chapter reviews the extant knowledge of these methodological issues. Our main message is that maximizing the validity of inferences should be the main concern of cross-cultural research and that methodological rigor in terms of establishing cross-cultural equivalence and suppressing bias across cultures plays a crucial role in this endeavor. We first describe a taxonomy of equivalence and bias, how they can be assessed, and the measures that can be taken to increase the validity of cross-cultural inferences. The second part gives an overview of procedures for adapting tests and survey questionnaires across cultures. Conclusions are presented in the final section.

Dealing with extreme environmental degradation: stress and marginalization of Sahel dwellers.

Background: Psychological aspects of environmental degradation are hardly investigated. In the present study these aspects were examined among Sahel dwellers, who live in environments with different states of degradation. The degradation was assessed in terms of vegetation cover, erosion, and loss of organic matter. Method: Subjects came from three cultural groups: Dogon (agriculturalists, n = 225), Mossi (agriculturalists, n = 914), and Fulani (pastoralists, n = 844). Questionnaires addressing marginalization, locus of control, and coping were administered. Results: Environmental degradation was associated with higher levels of stress, marginalization, passive coping (avoidance), a more external locus of control, and lower levels of active coping (problem solving and support seeking). Compared to agriculturalists, pastoralists showed a stronger variation in all psychological variables across all regions, from the least to the most environmentally degraded. Women showed higher scores of stress, (external) locus of control, problem solving, and support seeking than men. The interaction of gender and region was significant for several variables. Conclusion: It was concluded that environmental degradation has various psychological correlates: people are likely to display an active approach to environmental degradation as long as the level of degradation is not beyond their control.

Introduction to the methodological issues associated with cross-cultural research

Although once considered to be at the margins of psychological science, the study of culture has blossomed into one of the most important areas of research today. Studies involving cultural variables appear more frequently than ever before in mainstream journals in developmental, clinical, personality, and social psychology, as well as in specialty journals such as the Journal of Cross-Cultural Psychology, Culture and Psychology, International Journal of Intercultural Relations, and the Journal of Cross Cultural Management (van de Vijver, 2006). Theorists are also increasingly incorporating culture as an important variable into their theories and models of psychological processes. The methodological backbone spurring the blossoming of cultural science in psychology is cross-cultural research, in which two or more cultural groups are compared on psychological variables of interest. This is true regardless of the theoretical approach or perspective one adopts in understanding cultural influences on mind and behavior. For instance, methodological differences used to exist between those who called themselves cross-cultural psychologists versus those who called themselves cultural psychologists, with the former basing most of their work on cross-cultural comparison and the latter arguing that such comparisons were unwarranted, unjustified, and unnecessary (Greenfield, 1997; Shweder, 1999). Today, however, even those who call themselves cultural psychologists clearly use cross-cultural research methods as the method of choice in conducting research (e.g., Heine et al., 2001; Kitayama, Mesquita, & Karasawa, 2006; Markus, Uchida, Omoregie, Townsend, & Kitayama, 2006).

On the Study of Culture in Developmental Science

Cross-cultural developmental research faces the daunting task of studying the relationship of development and cultural context. The main argument of this article is that a variety of approaches is needed rather than one single perspective to make progress with this task. We illustrate how qualitative and quantitative research can be seen as complementary rather than mutually exclusive. We present four models, following Cole, that range from simple main effects to dynamic interaction models and argue that the debate about superiority of any one model is counterproductive; when applicable a more simple model is to be preferred. Thereafter a taxonomy of psychological domains is proposed (physiological, perceptual, cognitive, personality, and social aspects) that has a bearing on the choice of model. The final section describes some issues (and pseudoissues) of cross-cultural developmental science, such as the dichotomy between molar and molecular approaches, and the presumed need to maximize the understanding of cultural context in all research.

Types of comparative studies in cross-cultural psychology

From a methodological perspective cross-cultural studies in psychology differ in three dimensions. First, cross-cultural psychological studies can be exploratory or test specific hypotheses. Second, some cross-cultural studies compare countries or ethnic groups while other cross-cultural studies relate specific characteristics of a country or ethnicity (e.g., socialization patterns or religiosity) to psychological variables. Third, studies can compare either constructs (e.g., do Chinese and Kenyans mean the same when they say that a person is intelligent?) or score levels (e.g., are Americans more extravert than Italians?). A classification of cross-cultural psychological studies, based on the three dimensions, is presented and examples are given. Creative Commons License This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License. This article is available in Online Readings in Psychology and Culture: http://scholarworks.gvsu.edu/orpc/vol2/iss2/2

Methodology of Combining the WISC-III Data Sets

Publisher Summary The Wechsler test is one of the most used, individually administered, standardized measures for assessing intelligence in children and adults. The primary purpose of intelligence testing is to classify individuals based on their overall level of cognitive functioning. This chapter presents an overview of the items adapted and closely translated per subtest in each of the countries. This chapter provides the background for the statistical analyses. The overview provides insight in the judgmental bias of the subtest, which refers to nonstatistical procedures to identify bias, based on a content analysis of the items. All local test development teams had to address two issues: which American items were expected to be transferable to a new linguistic and cultural context without major alterations, and which items were assumed to require adaptations. As a consequence, country comparisons of the number of adapted items of the 11 subtests provide information about the judgmental bias in these subtests.

Group differences in structured tests

During the last two decades much effort has been put into developing and refining procedures to detect bias in test items. Bias is defined here as any effect on an observed score which is not found to an equal extent in the psychological universe to which the scores are generalised (cf. Poortinga and Van de Vijver, in press). The vast majority of publications on this subject has appeared in methodologically oriented journals; remarkably few references are made to the bias tradition in journals implicitly devoted to intergroup comparisons. Apparently, the study of item bias has neither created nor met a strong demand among cross-cultural psychologists. Although it can be argued that this is simply a matter of time, it seems more likely that the item bias tradition will influence applied research only to a limited degree because of the conceptual rigidity of the approach. Item bias procedures are post hoc procedures meant to detect items with differential statistics across groups. When a test is administered to people of two cultures and differences in endorsement rates are the same for all items, except for one item which shows a larger difference, this latter item is typically considered to be biased. Items are dichotomously labelled as biased or unbiased.

Cross-cultural research methods

Cross-cultural studies involve persons from different countries and/or ethnic groups. One of the central methodological problems of these studies is bias, the generic term for rival explanations of cross-cultural differences. Three different types of bias are distinguished, depending on whether the source of interpretation problems derives from the construct, method of the study, or specific items (called construct, method, and item bias or differential item functioning, respectively). Equivalence refers to the implications of bias on score comparability. Linguistic, structural, measurement unit, and full score equivalence are described. Issues in test translation (translation—back-translation, committee designs, decentering) are discussed. Common subject- and culture-sampling schemes in cross-cultural research are mentioned. The article ends with a discussion of issues in combining individual- and country-level characteristics.