Psychometric Test Performance Research Articles

Psychometric tests for assessment of brain function after solvent exposure.

Psychometric testing is a key issue in neuropsychological toxicology assessment. Evaluation of methods for assessing general intellectual impairment is necessary as conventional neurology has been shown to be insensitive to the neurotoxic effects of solvents and metals. This study presents an analysis of a psychometric test battery from an investigation of psycho-organic syndrome in a historical cohort of 96 metal degreasers with long-term exposure to solvents, particularly trichloroethylene. The neuropsychological test battery was a combination of Wechsler Adult Intelligence Scale (WAIS), Luria, and tests developed in Scandinavia. Linear regression analysis showed a significant dose-response relation between increasing cumulative solvent exposure and impaired psychometric test performance in 9 out of 15 tests. Multivariate analysis, however, suggests that much of the variance was due to confounding variables, especially age, and to a lesser degree, primary intellectual function and word blindness. After control for confounding factors the strongest association with solvent exposure occurred for the following three tests: acoustic-motor function, Paced Auditory Serial Addition Test (PASAT), and the visual gestalt test.

Trichinosis: a prospective controlled study of patients ten years after acute infection.

The existence of chronic trichinosis as a disease entity is still a matter of debate. For 10 years after an outbreak of infection with Trichinella spiralis, we conducted a prospective controlled study of the patients involved. At the termination of this investigation, we undertook clinical, biochemical, serological, immunologic, neuroradiological, radiological, and psychological studies of 128 originally infected persons and 16 controls. The categories of symptoms most often documented in persons who had been infected were muscular (90%), ocular (59%), neurological (52%), and psychological (52%). Impaired muscle strength (56%), conjunctivitis (55%), and impaired coordination (32%) were the clinical manifestations most frequently encountered. Thirty-eight percent of the 128 originally infected patients still had IgG antibodies to T. spiralis after 10 years. Magnetic resonance imaging of the brain revealed no abnormalities. No calcifications of residual larvae were detected by mammography or muscle biopsy. The level of performance in psychometric tests was lower in the originally infected population than in the general population. Although patients who had had trichinosis differed significantly from controls in terms of a variety of parameters even after 10 years, we found insufficient evidence on which to conclude that chronic trichinosis exists as a distinct entity.

Does cetirizine belong to the new generation of antihistamines? An investigation into its acute and subchronic effects on highway driving, psychometric test performance and daytime sleepiness

AbstractTwenty‐seven healthy male volunteers participated in a double‐blind, five‐way crossover designed comparison of the new, selective H1‐receptor antagonist cetirizine (10 mg q.d.) and terfenadine (60 mg b.i.d. and 120 mg q.d.) versus the older H1‐receptor antagonist triprolidine (5 mg b.i.d.) and placebo.Medication was administered during four consecutive days. Subjects were tested on the 1st and 4th treatment day. On each test day subjects drove an instrumented vehicle over a 100 km highway circuit while attempting to maintain a constant speed (90 km/hr) and a steady lateral position within the right traffic lane. Thereafter they performed three computerized memory tasks. On the 4th treatment day, sleep latency was measured before and after the driving test. On both days, triprolidine significantly impaired performance in the driving and psychometric tests. Triprolidine also significantly reduced sleep latency in comparison to placebo on the 4th treatment day. Terfenadine 60 mg b.i.d. impaired psychometric performance after subchronic treatment.It was concluded that cetirizine, like terfenadine, belongs to the newer class of antihistamines and can be safely used by patients who continue their daily activities.

DIF: A Computer Program for the Analysis of Differential Item Performance

A FORTRAN 77 program is presented which performs analyses of differential item performance in psychometric tests. The program performs the Mantel-Haenszel procedure and computes various additional classical indices of differential item functioning (including discrimination indices) as well as associated effect size measures.

Psychometric intelligence and performance on selective reminding

Abstract The relationship between psychometric intelligence and Selective Reminding Test (SRT) performance was examined using the data from 60 college students, aged 18 to 35. Subjects were divided into four groups (Low Average, Average, High Average, and Superior) on the basis of their Satz-Mogel Full Scale WAIS-R IQ. MANOVA yielded significant group differences for five of the SRT scores wherein the Low Average group's performance was significantly lower than that of the High Average and Superior groups. Gender differences emerged for four of the SRT dependent measures, with women scoring higher than men independent of group membership. No significant gender differences emerged on IQ. Results suggest that psychometric intelligence is moderately related to SRT performance. The scores of the Low Average group fell approximately 1 SD below comparable SRT normative data. These results suggest that the use of SRT normative data which does not consider intellectual level may put clinicians at risk of overesti...

Effects of centrophenoxine on body composition and some biochemical parameters of demented elderly people as revealed in a double-blind clinical trial

A double-blind clinical trial was performed on 50 persons (25 men, 25 women, average age 77 years) suffering from dementias of medium level (DSM III, Category 1, ICD No. 299). All subjects were residents in an old age home. The patients were treated first for 2 weeks by placebo tablets. During this period, body composition parameters were determined and these data served as controls. This was then followed by an 8-week-long treatment with the nootropic drug, centrophenoxine (CPH), 2 g/day distributed in 2×2 tablets of Helfergin 500 (Promonta, Hamburg, F.R.G.), or placebo tablets of identical size. After 8 weeks the laboratory tests were repeated again. The randomization code for verum or placebo treatment was revealed only after completing the trial. Four dropouts occurred during the treatment period. The total body water, extracellular water volume and exchangable Na + were determined by means of radioisotope methods. Plasma volume (PV) was measured by indocyanine-green dilution test. Body weights were also recorded. From the above data further parameters could be calculated. Serum lipid data as well as several hormone levels were also checked in the blood samples. The main results were better performance in psychometric tests (Pék et al., 1989) and a significant increase of the average intracellular water content (2.2–2.5% by weight) in the verum-treated group. The rehydration of the intracellular mass due to CPH treatment is consistent with the OH •. free radical scavenger properties of CPH and the predictions of the membrane hypothesis of aging.

A multidimensional approach in testing nootropic drug effects (Cerebrolysin®)

In an attempt to improve indicators of validity for the therapeutic efficacy of nootropics, the effects of Cerebrolysin® were compared across three different dimensions of variables in a randomized placebo-controlled double-blind study. A group of 27 geriatric patients suffering from an organic brain syndrome with moderate cognitive impairment of a vascular or/and degenerative nature received a series of ten Cerebrolysin + multivitamin infusions. They were compared to a second group with 14 clinically comparable patients, who received multivitamin infusions alone. Pre-posttreatment differences from (1) clinical scales (SCAG, Plutchik Geriatric Rating Scale and a self-evaluation scale); (2) psychometric test performance (trail-making and maze subtests from the Nürnberg Age Inventory); and (3) event-related brain activity (contingent negative variation (CNV) amplitude) were in favor of the Cerebrolysin-treated group. A high degree of association as well as high classification rates (95% joint correct classification) underlined their clinical significance. It was concluded that the multidimensional measurement approach could increase the clinical validity of nootropic drug effects.

Long-term follow up of workers exposed to solvents.

Long term occupational exposure to organic solvents may cause adverse effects to the central nervous system. This collaborative study between six Swedish departments of occupational medicine examines the overall prognosis in terms of working capacity, symptoms, and psychometric test performance for individuals occupationally exposed to organic solvents. After re-analyses of the data from an initial clinical investigation of 111 men, the subjects were divided into two subgroups: one group of 65 with symptoms but no impairment on the tests and one group of 46 with toxic encephalopathy (symptoms and test impairment). At least five years after the initial examination the subjects were asked to attend a re-examination that included a structured medical interview and a psychometric investigation. The results indicate that effects on the central nervous system persist even when exposure has ceased. In the group of 46 more men had stopped working and were receiving sickness or early retirement pensions. This group also had reduced activity levels with regard to everyday life, leisure activities, and education or training and more neuropsychiatric symptoms. There was no support for the view that a solvent induced toxic encephalopathy is a progressive disease comparable with presenile dementia such as Alzheimer's disease or Pick's disease. If a worker was removed from exposure when he presented symptoms without signs of impairment in intellectual function recovery was seen in most cases.

Health and development of 8-year-old children whose mothers abused amphetamine during pregnancy.

Sixty-five children whose mothers were addicted to amphetamine during pregnancy were followed prospectively until eight years of age, when they were tested in their homes. Only 21 children (30%) remained in the custody of their biological mothers. Their physical health, including growth, was normal. Their IQ and their performance in several psychometric tests were within normal limits. Increased incidences of aggressive behaviour and peer-related problems were found, especially in the groups that had been exposed to amphetamine throughout pregnancy. No correlation was found with socio-environmental factors.

Links between personality, ability and attitudes in a low-IQ sample

Despite considerable reference to those on the Youth Training Scheme (YTS), little is known of their psychometric test performance. YTS trainees were tested on measures of verbal and non-verbal intelligence, personality, attitudes and hostility. The range of ability in the sample varied considerably: one third (30) of the subjects had IQs less than 90, 10 of these having IQs below 75. The remainder had IQs ranging from 90 to 117 (median IQ = 98). YTS trainees were higher in neuroticism ( N), psychoticism ( P), lie-telling ( L) and social conservatism ( C) than norms for a sample of similar age and sex. Correlations between tests suggest that IQ has a significant negative correlation with C ( r = - 0.39, P < 0.001), outwardly expressed hostility and L, whilst L is strongly linked to C ( r = 0.53, P <0.001) and C subscales. P was strongly correlated with measures of outwardly-directed hostility (mean r = 0.39, P < 0.001), while N was correlated at a similar magnitude to measures of inwardly expressed hostility. Sex differences reflected earlier findings: females were significantly more neurotic than males, males more overtly hostile (and had higher P scores) than females. The SPM/C correlation is discussed in relation to the view that the apparent rise in global IQ is a product of reduced social conservatism.

Neurasthenic complaints and psychometric function of toluene-exposed rotogravure printers.

In 1985, 30 rotogravure printers exposed to toluene for 4-43 years (median 29) were examined by means of interviews and psychometric testing. They were 33-61 years of age (mean 50). Comparisons were made with a reference group of 72 men aged 27-69 (mean 47). The referents had never been exposed to solvents and were all in good health. The printers were employed by two Swedish companies. The mean exposure levels were 43 and 157 mg/m3 of toluene, respectively, at the two printing shops. Before 1980 the exposure levels had exceeded 300 mg/m3. On Monday mornings, before psychometric testing at the department of occupational medicine, toluene was measured in venous blood samples from most of the exposed subjects. A high proportion of the printers reported fatigue (60%), recent short-term memory problems (60%), concentration difficulties (40%), mood lability (27%), and other neurasthenic symptoms. In the psychometric tests their performance was poorer than the reference group's in most of the tests applied. Even performance on the synonyms test, usually considered resistant to mild brain affliction, was worse in the group of printers. Adjusting for this difference in the group comparisons reduced the group differences substantially. Alcohol consumption above 200 g/week was found to reduce the subjects' psychometric function more than toluene exposure. The printers' sum of neurasthenic complaints correlated negatively with their score in several tests. Exposure variables showed only weak associations with test results. Blood toluene levels were positively correlated with scores in spatial tests. The direction of the correlations suggests that the influence of acute pharmacologic effects is undetectable on Monday mornings before work. In conclusion, we found that exposure to toluene at levels below 157 mg/m3 following long-term exposure did induce neurasthenic problems and might reduce psychometric test performance.

Vividness, spatial manipulation, and spontaneous elaboration: A critical evaluation of the use of factor analysis by Lorenz and Neisser (1985)

On the basis of factor analyses of questionnaire responses and psychometric test performance, Lorenz and Neisser (1985) argued for the existence of three distinct imagery factors: vividness and control, spatial manipulation, and spontaneous elaboration. Their use of factor analysis is criticized under three headings: the choice of the number of factors to be extracted, the choice of analytic model, and the choice of rotation model. On the basis of alternative analyses, it is concluded that the results of Lorenz and Neisser’s investigation tend to support the established distinction between introspective judgments of experienced imagery and objective performance in tests of spatial thinking, but that there is no evidence for a third factor of spontaneous elaboration.

Relationships between blood lead, behaviour, psychometric and neuropsychological test performance in young children

A sample of 201 inner city dwelling children age 5.5 years was assessed on a wide variety of cognitive, performance, neuropsychological and behavioural measures. Extensive sociodemographic and family indices were also assessed. Body burden of lead was derived from a venous sample of blood. Data were analysed using both univariate and multivariate techniques. Results show that the initial correlations between blood lead and the outcome measures were generally few and low. No significant relationship was found between overall IQ and blood lead and the one marginally significant association found when the sample was split by father's occupation proved non‐significant on multivariate analysis. The only outcome measures that showed a significant association with blood lead following multivariate analysis were some tests requiring motor skills (where performance generally speeded up with increasing blood lead) and one reaction time measure where the converse obtained.

Mental models of mechanical systems: Individual differences in qualitative and quantitative reasoning

People who understand mechanical systems can infer the principles of operation of an unfamiliar device from their knowledge of the device's components and their mechanical interactions. Individuals vary considerably in their ability to make this type of inference. This paper describes studies of performance in psychometric tests of mechanical ability. Based on subjects' retrospective protocols and response patterns, it was possible to identify rules of mechanical reasoning that accounted for the performance of subjects of different levels of mechanical ability. The rules are explicitly stated in a simulation model which demonstrates the sufficiency of the rules by producing the kinds of responses observed in the subjects. Three abilities are proposed as the sources of individual differences in performance: (1) ability to correctly identify which attributes of a system are relevant to its mechanical function, (2) ability to use rules consistently, and (3) ability to quantitatively combine information about two or more relevant attributes.

Individual differences in television comprehension.

Two experiments explored individual differences in memory and comprehension for adults presented information on television. Experiment 1 tested the correlation between comprehension of television and reading with young adults. The ability to comprehend these two forms of media was significantly correlated (r = .69). This finding is contrary to results from our previous study with third and sixth graders (Pezdek, Lehrer, & Simon, 1984). Experiment 2 probed two specific individual differences factors as predictors of television comprehension. The results were that good television comprehenders (1) had higher visual/spatial ability, as assessed by psychometric test performance, and (2) were more likely to utilize an imagery-based strategy in the sentence-picture verification task of Clark and Chase (1972) (e.g., “STAR IS ABOVE PLUS”). These results suggest differences in the comprehension processes that operate on information presented in different forms of media.

Neuropsychological study of children during and after remission of endogenous depressive episodes.

2 children experiencing endogenous depressive episodes show impaired cognitive functioning. Following tricyclic antidepressant-induced remission of depression, there was significant improvement in psychometric test performance.

Levodopa and psychometric test performance in parkinsonism-5 years later.

Forty parkinsonian patients on levodopa therapy for a mean of 4 years and 10 months were given a battery of psychometric tests to assess memory cognition, and perception. Three equated control groups consisting of (1) parkinsonian patients not on levodopa, (2) patients on short-term levodopa, a mean of 1 year and 1 month, and (3) spouses, were administered a similar battery. The experimental group performed better than the nonlevodopa and the short-term groups on two subtests of intellectual functioning, but did less well on two tests of recent memory. All three parkinsonian groups consistently did significantly worse than spouses. When sex, age, and other relevant variables are equated, longer term levodopa therapy does not significantly after the overall pattern of psychometrically tested functions generally reported in parkinsonian patients.

Are Behavioral and Psychometric Changes Related in Methylphenidate-Treated, Hyperactive Children?

Improvement in psychometric test performance as well as in behavior has been consistently observed among hyperactive children treated with stimulants. In some publications there is either the expressed or implied opinion that the improved cognitive functioning is an end in itself, suggesting that the improvement is evidence of the drug's more general beneficial effects (Campbell, Douglas, & Morgenstern, 1971). More important, the positive effects of stimulants on psychometric test results have been used for deriving theories explaining how stimulants benefit the behavior of hyperactive children. It is argued quite convincingly that stimulants do not have a paradoxical effect on hyperactive children, but rather that they act as central nervous system (CNS) stimulants enhancing attention-arousal processes; this improvement enables the child to focus and attend. Secondary to improved attention, the child is more controlled and focused, less impulsive and distractible (Conners, 1973; Douglas, 1972; Ellis, Witt, Reynolds, & Sprague, 1974; Kinsbourne, 1974; Satterfield, Cantwell, Lesser, & Podosin, 1972). This change is interpreted by the caring adults as a reduction in hyperactivity. The hypothesis is that motor activity is not quantitatively reduced but qualitatively improved by the stimulants. The child does not stop moving, but his movements become goal directed and meaningful, rather than haphazard, unfocused, and purposeless. If the above interpretation is correct, one possible consequence would be that children who responded to stimulants would improve both in behavior and in test performance, so that those whose

Psychometric test performance in relation to the psychopathology of epilepsy.

Clinical, electroencephalographic, and psychologic test data from 49 adults with diagnoses of temporal-psychomotor, generalized, or focal epilepsy were examined statistically in order to determine whether cognitive, perceptual, or memory dysfunctions were significantly correlated with the incidence and quality of psychopathology. No significant relationship could be shown between deficits in psychometric test performance and quality or degree of psychiatric abnormality.

An hallucinogenic amphetamine analog (DOM) in man.

The amphetamine analog, 2,5-dimethoxy-4-methylamphetamine (DOM), was studied in 18 volunteer subjects given single doses ranging from 2 to 14 mg. The former was a threshold dose, with definite psychotomimetic effects being evident from doses over 5 mg. The clinical syndrome greatly resembled that of the LSD-mescaline-psilocybin series of drugs, including its time-course. Somewhat more sedation was produced by DOM than would have been expected from the others, despite concomitant evidence of peripheral sympathetic stimulation. Just as with the other drugs, DOM increased plasma free fatty acids, decreased phosphorus and creatinine clearance, decreased circulating eosinophils and had little effect on catecholamine excretion. Performance of psychometric tests was impaired. Chlorpromazine treatment concurrently was found to attenuate the reaction. Tolerance rapidly developed when the drug was used chronically by patients.