Predicting WAIS scores form quick test scores for mentally retarded psychiatric patients

Investigated Quick Test prediction of WAIS Full Scale IQs for a psychiatric population (N = 19) who were also mentally retarded. One- and two- variable regression equations produced nonsignificant results and accounted for only 11% and 15% of the variance. Caution is advised when the Quick Test is used as an estimate of IQ for mentally retarded psychiatric individuals.     

提重辨别实验中精神发育迟滞儿童的反应特征

采用提重辨别实验对精神发育迟滞儿童(MR)和正常儿童进行了测试比较。结果表明,MR 儿童左手、右手和双手测试成绩间虽未产生显著性差异,但此三种测试条件下的辨别能力明显低于正常儿童。提示其大脑两半球认知功能存有缺陷,不支持国外 MR 儿童认知功能障碍的“左脑障碍”或“右脑障碍”假说。测试中 MR 儿童有明显的不肯定判断倾向,似可作为 MR 儿童高层认知结构的特性反应。     

Detecting symptom- and test-coached simulators with the test of memory malingering.

The ability of the Test of Memory Malingering (TOMM; Tombaugh, 1996) to detect feigned-memory impairment was explored. The TOMM was administered to three groups: (a) a control group instructed to perform optimally, (b) a symptom-coached group instructed to feign memory problems after being educated about traumatic brain injury symptomatology, and (c) a test-coached group instructed to feign memory problems after being educated about test-taking strategies to avoid detection. The recommended cutoff scores (Tombaugh, 1996) on Trial 2 and the Retention Trial produced overall classification accuracy rates of 96%, with high levels of sensitivity and specificity. Although the symptom-coached group performed more poorly on the TOMM relative to the test-coached group, the test was equally sensitive in detecting suboptimal effort across the different coaching paradigms.     

Performance of substance abusers with memory deficits on measures of malingering.

The effects of memory impairment on various malingering indices were assessed in a substance abusing population. Groups were formed by using scores from the Delayed Memory Index of the Wechsler Memory Scale-Revised and selecting individuals from an addictions recovery unit in the top and bottom quintiles. Quintile group differences were found for number correct on free and forced-choice recall on the 21-Item Wordlist; total time for grouped and ungrouped dots on the Rey Dot Counting procedure; and addition errors on the Memorization of 16 Items test. All differences found were in the direction of better performance by subjects with better Delayed Memory Index scores; however, all of the differences were small. With the exception of the free recall index from the 21-Item Wordlist, all subjects had scores on the malingering measures beyond the cutoffs typically used to detect malingering in clinical populations. These findings suggest that, even in memory-impaired populations, memory measures of malingering are valid.     

The use of the rey memory test to assess malingering in criminal defendants

An attempt was made to evaluate the utility of the Rey Memory Test (Rey, 1964) to assess malingering in criminal defendants referred for inpatient forensic evaluation. The performance of 14 diagnosed malingerers was compared to a control group of 14 forensic inpatients who had been acquitted by reason of insanity. Malingerers performed significantly less well on the test than did controls. A previously suggested cut-off score of 9 items remembered (Lezak, 1983) resulted in correct classification of 86% of the subjects as either malingering or not malingering. However, a cut-off of 3 rows remembered correctly was found to be inappropriate because 57% of the controls would have been labeled incorrectly as malingerers.     

Entamoeba histolytica autochthonous isolates from mentally retarded Italian patients

A total of 77 mentally retarde male inpatients residing in a psychiatric institution in northern Italy were screened for the presence of stool parasites,Entamoeba histolytica particularly. Parasitological stool examination showedEntamoeba spp. (E. histolytica and/orE. dispar) in 26 cases (33.7%). In vitro culture on Robinson's medium was positive in 16 cases (61.1%); in 11 cases we could stabilize and clone the isolates and proceed to electrophoretic assays. In all cases, patterns of pathogenic zymodemes were found (zymodeme II, 3 isolates; zymodeme XII, 4 isolates; zymodeme XIV, 4 isolates). All isolates were therefore identified asE. histolytica.     

The validity of the letter memory test as a measure of memory malingering: robustness to coaching.

The letter memory test (LMT) is a computerized forced-choice test of malingering detection including two face valid difficulty manipulations: increase in target stimulus length and increase of response foils. Prior research suggests the LMT shows promise as a malingering detection measure. In the present study, the utility of the LMT in the identification of malingering was further explored, using a counterbalanced design in a simulated malingering sample. Prior work was extended by assessing the robustness of the LMT to coaching and assessing the effectiveness of an additional scoring method, utilizing the face valid difficulty manipulations. Results were consistent with prior research on the LMT, with the standard cutoff score yielding high indices of accuracy. The LMT showed no order effects and was superior to the 15-item test in accuracy indices. Both the standard LMT score and the proposed score based on difficulty manipulations were relatively robust to coaching. Overall, findings indicate the LMT is a viable contender among measures of memory malingering.     

FRAXE mutation in mentally retarded patients using the OxE18 probe

The folate-sensitive fragile site FRAXE is located in proximal Xq28 of the human X chromosome and lies approximately 600 kb distal to the fragile X syndrome (FRAXA) fragile site at Xq27.3. Although FRAXA and FRAXE are indistinguishable by means of conventional cytogenetics, they can now be delineated at the molecular level and provides the basis for a proper diagnosis. The screening for CGG amplifications in the FMR1 gene was based on standard protocols using EcoRI digests on Southern blots and hybridization with the StB12.3 probe. The FRAXE mutation was analyzed by digestion with HindIII and the filters were probed with OxE20. We present the results of 144 patients referred for fragile X testing but negative for the FMR1 gene trinucleotide expansion, that were also screened for the FMR2 expansion. For FRAXE mutation a molecular protocol for OxE18 probe was used, in the DNA samples digested with EcoRI on the same blots as those used for detection of FRAXA. None of the patients tested were positive for the FRAXE expansion. This technique was successfully established into our laboratory routine showing the practical use of testing for FRAXA and FRAXE in a large series of patients.     

Disease profile of 400 institutionalized mentally retarded patients in Kuwait

Farag TI, Al-Awadi SA, El-Badramary MH, Aref MA, Kasrawi B, Krishna Murthy DS, El-Khalifa MY, Yadav G, Marafie MJ, Bastaki L, Wahba RA, Mohammed FM, Abul Hasan S, Redha AA, Redha MA, Al-aboud H, Al-Hijji S, Al-Dighashem D, Al-Hashash N, Al-Jeeryan L, Al-Khor-afi H, Qurban EA, Al-Sulaiman I. Disease profile of 400 institutionalized mentally retarded patients in Kuwait.
Clin Genet 1993: 44: 329–334. © Munksgaard, 1993
In this preliminary report we summarize the results of a 4-year multidisciplinary systematic, etiological clinicogenetic survey of 400 institutionalized mentally retarded patients in Kuwait. All had an intelligence quotient below 50. A constitutional disorder, as the direct cause of the mental retardation, was found in 203 patients (50.75%)): a chromosomal abnormality in 37 (9.25%), Mendelian disorders in 137 (34.25%), MCA/MR in 22 (5.55%) and CNS malformations in 7 cases (1.75%). In 157 patients (39.35%) a pre-, peri or postnatal cause was ascertained. No etiological diagnosis was detected in 40 patients (10%). A detailed analysis of the "disease profile" is given and compared with the results of previous diagnostic genetic surveys among different institutionalized mentally retarded populations in Western and developing countries.     

Bone mineral in mentally retarded patients receiving long-term anticonvulsive therapy.

A direct photon absorptiometry method was used to measure bone mineral content in a population of mentally retarded subjects, one half of whom were undergoing long-term anticonvulsant drug therapy. The sample consisted of 134 subjects, 60 males and 74 females. Average ages were 22.5 years for the females and 19.7 years for the males. A multiple regression analysis showed there was no apparent effect on anticonvulsant drug therapy on bone mineral content in this mentally retarded and growth retarded population. A comparison with normal standards indicates that bone mineral values for age for both sexes of mentally retarded subjects were depressed from 15-40 percent relative to white standards. The bone mineral depression closely paralleled the growth depression seen in this population. It is suggested that the inability to detect an overall anticonvulsive drug effect on bone mineral values may be due to the general growth retardation seen in this institutionalized mentally retarded population.     

Additional cryptic CNVs in mentally retarded patients with apparently balanced karyotypes

Apparently balanced chromosome abnormalities are occasionally associated with mental retardation (MR). These balanced rearrangements may disrupt genes. However, the phenotype may also be caused by small abnormalities present at the breakpoints or elsewhere in the genome. Conventional karyotyping is not instrumental for detecting small abnormalities because it only identifies genomic imbalances larger than 5–10 Mb. In contrast, high-resolution whole-genome arrays enable the detection of submicroscopic abnormalities in patients with apparently balanced rearrangements.Here, we report on the whole-genome analysis of 13 MR patients with previously detected balanced chromosomal abnormalities, five de novo, four inherited, and four of unknown inheritance, using Single Nucleotide Polymorphism (SNP) arrays. In all the cases, the patient had an abnormal phenotype. In one familial case and one unknown inheritance case, one of the parents had a phenotype which appeared identical to the patient’s phenotype. Additional copy number variants (CNVs) were identified in eight patients. Three patients contained CNVs adjacent to one or either breakpoints. One of these patients showed four and two deletions near the breakpoints of a de novo pericentric inversion. In five patients we identified CNVs on chromosomes unrelated to the previously observed genomic imbalance.These data demonstrate that high-resolution array screening and conventional karyotyping is necessary to tie complex karyotypes to phenotypes of MR patients.     

A cytogenetic survey of 449 patients in a Japanese institution for the mentally retarded

A cytogenetic survey was carried out on 449 patients (261 males and 188 females) in an institution for the mentally retarded in Japan. A total of 37 patients (8.1 %) were shown to have chromosome abnormalities. There were 33 individuals (7.3 %) with 21 trisomy. In addition, we found one patient with 46,XY/47,XY, + 12p, one with 46, XY, r(22), and one with 45, XY, -13, -14,+t(13q14q). Only one female was found to have an abnormal sex chromosome constitution, 47, XXX. The significant contribution of chromosome abnormalities in the etiology of mental retardation is also shown in the present survey. The most common chromosome abnormality was 21 trisomy, as seen in other similar surveys.