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The European Union has seen an increased number of asylum seekers and economic migrants over the past few years. There will be request to assess some of these individuals to see if they have an intellectual disability (ID). If this is to be done using the current internationally recognized definitions of ID, we will need to be confident that the IQ tests we have available are able to accurately measure the IQs of people from developing countries. The literature showing substantial differences in the mean measured IQs of different countries is considered. It is found that, although there are numerous problems with these studies, the overall conclusion that there are substantial differences in mean measured IQ is sound. However, what is not clear is whether there are large differences in true intellectual ability between different countries, how predictive IQ scores are of an individual from a developing country ability to cope, and whether or not an individual's IQ would increase if they go from a developing country to a developed one. Because of these uncertainties, it is suggested that a diagnosis of ID should not be dependent on an IQ cut-off point when assessing people from developing countries.

Background: Previous research with earlier versions of the WISC and WAIS has demonstrated that when administered to people who have intellectual disabilities, the WAIS produced higher IQ scores than the WISC. The aim of this study was to examine whether these differences still exist. A comparison of the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) with the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) was conducted with individuals who were 16 years old and receiving special education. Materials and Methods: All participants completed the WAIS-III (UK) and WISC-IV (UK). The order of administration was counterbalanced; the mean Full Scale IQ and Index scores on the WAIS-III and WISC-IV were compared. Results: The WAIS-III mean Full Scale IQ was 11.82 points higher than the mean Full Scale IQ score on the WISC-IV. Significant differences were also found between the Verbal Comprehension Index, Perceptual Reasoning/Organization Index and Processing Speed Index on the WAIS-III and WISC-IV, all with the WAIS-III scoring higher. Conclusions: The findings suggest that the WAIS-III produces higher scores than the WISC-IV in people with intellectual disabilities. This has implications for definitions of intellectual disability and suggests that Psychologists should be cautious when interpreting and reporting IQ scores on the WAIS-III and WISC-IV.

The WISC-IV is likely to be in common use for the assessment of children with low intellectual ability for the next 10-12 years. There are several concerns about its uses with these children. Some children may not understand the instructions on some subtests, notably for letter-number sequencing. There may be an unacknowledged floor effect that will result in an overestimate of intellectual ability. The percentile ratings given in the manual are inaccurate for percentiles below 1%. Evidence is presented that the WISC-IV may systematically give lower IQ scores than the WAIS-III when assessing low IQ.

A meta-analysis of the stability of low IQ (IQ less than 80) was performed on IQ tests that have been commonly used--tests that were derived by D. Wechsler (1949, 1955, 1974, 1981, 1991, 1997) and those based on the Binet scales (L. M. Terman, 1960; L. M. Terman & Merrill, 1972). Weighted-mean stability coefficients of 0.77 and 0.78 were found for Verbal IQ (V IQ) and Performance IQ (P IQ) on the Wechsler tests and 0.82 for Full-Scale IQ (FS IQ) on both Wechsler and Binet tests, for a mean test-retest interval of 2.8 years. Although the majority of FS IQs changed by less than 6 points, 14% changed by 10 points or more. The author suggests that the results of IQ assessment should be treated with more caution than previously thought.

Objective: It has been suggested that, as the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) and the Wechsler Intelligence Scale for Children-Third Edition (WISC-III) give a scaled score of one even if a client scores a raw score of zero, these assessments may have a hidden floor effect at low IQ levels. The study looked for indications of this in a sample of assessments that had been given for clinical and diagnostic reasons. Design: The degree to which a hidden floor effect could be present was assessed by looking at the proportion of scaled scores of one in IQ bands: 50-59, 60-69 and 70 plus and by plotting the distribution of scaled scores in these bands for both the WISC-III and WAIS-III. Method: Fifty WISC-III and 49 WAIS-III assessments were obtained from records and analysed. Results: The distribution of scaled scores in the WAIS-III was approximately normal with very few scale scores of one, suggesting that a hidden floor effect would only be a potential problem for IQs in the 40s and 50s. The WISC-III had a skewed distribution of scaled scores with more scaled scores of one than any other scaled score. Scaled scores of one were shown in all IQ levels up to 70 plus. Conclusions: There is potentially a significant floor effect on the WAIS-III at IQs in the 40s and 50s and on the WISC-III up to IQs in the 70s. There are also indications that the WISC-III has a much harder criterion for gaining a scaled score of two than the WAIS-III, resulting in it producing lower IQs.

Background: It has often been stated that the prevalence of psychiatric disorders in people with intellectual disabilities is greater than it is in the population as a whole. Method: The epidemiological studies on psychiatric disorders in people with intellectual disabilities were reviewed. Results: There is evidence that the prevalence of psychiatric disorder is greater in children with intellectual disabilities, compared with children with normal IQs, that it is higher in both adults and children with severe intellectual disabilities compared with people with mild or no intellectual disability and that the rate of problematic behaviour is higher in both adults and children having intellectual disabilities, than in their non-disabled peers. Conclusions: There is no sound evidence that the prevalence of psychiatric disorders in adults with mild intellectual disability is greater than in the population as a whole.

It is argued that challenging behavior can be better understood if a correlational analysis (looking for correlations between behavior occurrence and other variables) is used in addition to functional analysis. A case example is provided of a man whose aggressive outbursts were negatively correlated with trips out of his unit. (Contains references.) (Author/CR)

Abstract Pseudoaneurysms related to the superior mesenteric artery (SMA) are a recognised complication of trauma to the vessel, and successful treatment with stenting has been previously described. We report the case of a patient who presented with obstruction of the fourth part of the duodenum secondary to a traumatic pseudoaneurysm, a hitherto unreported variant of superior mesenteric artery syndrome. Exclusion of the pseudoaneurysm and relief of the duodenal obstruction were simultaneously achieved by placement of a covered stent.