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K M Adams

Publications and source records attributed to K M Adams.

At least 55 records · Page 3Linked to original sources
PubMed1985

Analysis of covariance as a remedy for demographic mismatch of research subject groups: some sobering simulations.

Analysis of Covariance (ANCOVA) is often used in neuropsychological studies to effect ex-post-facto adjustment of performance variables amongst groups of subjects mismatched on some relevant demographic variable. This paper reviews some of the statistical assumptions underlying this usage. In an attempt to illustrate the complexities of this statistical technique, three sham studies using actual patient data are presented. These staged simulations have varying relationships between group test performance differences and levels of covariate discrepancy. The results were robust and consistent in their nature, and were held to support the wisdom of previous cautions by statisticians concerning the employment of ANCOVA to justify comparisons between incomparable groups. ANCOVA should not be used in neuropsychological research to equate groups unequal on variables such as age and education or to exert statistical control whose objective is to eliminate consideration of the covariate as an explanation for results. Finally, the report advocates by example the use of simulation to further our understanding of neuropsychological variables.

Adult↗
PubMed1984

Aging, abstinence, and medical risk factors in the prediction of neuropsychologic deficit among long-term alcoholics.

Halstead-Reitan assessments were conducted with 71 male alcoholics sober for four weeks, 65 alcoholics sober for four years, and 68 nonalcoholics. Recently detoxified alcoholics showed learning and problem-solving difficulties, as did older persons in all groups. Aging, not alcoholism, was related to psychomotor slowing. There were no age-alcohol interactions for any neuropsychologic test. Time since last drink predicted neuropsychologic performance modestly, as did head injury, age, and education. Long-term sober alcoholics were indistinguishable from controls. Our results suggest that alcoholics abstinent one month suffer a subacute alcohol-related organic mental disorder that might resolve with prolonged abstinence, that the neuropsychologic findings in such alcoholics are more consistent with an "independent decrements" rather than "premature aging" hypothesis, and that neuromedical and other risk factors must be considered before permanent neuropsychologic deficit among alcoholics can be attributed solely to neurotoxic effects of alcohol.

Adult↗
PubMed1984

Relative accuracy of three automated systems for neuropsychological interpretation.

Three computer programs for automated interpretation of variants of the Halstead-Reitan Neuropsychological Test Battery were tested on cases in two data sets. The Key approach of Russell, Neuringer, and Goldstein (1970), Brain I (Finkelstein, 1977), and Adams' (1975) ability-based algorithm were employed in the study. The first data set included 63 well-documented cases with precise criterion data and multiple sources of direct verification. The second data set consisted of 30 equally well-studied cerebrovascular disease patients whose cerebral circulation disorders resulted in clinical manifestations encompassing the entire range of stroke. Results suggested that, while none of the programs do poorly at identifying the presence of brain damage, lateralization and possibly other localization/process predictions are not done well by these programs. The failure described in this particular study does not imply that automated methods are potentially less effective than true actuarial or clinical ones. Rather, we suggest that the translation process from clinical interpretation to the mechanical combinatory logic of the digital computer is at an early stage.

Aged↗
PubMed1984

Luria left in the lurch: unfulfilled promises are not valid tests.

The Luria-Nebraska Neuropsychological Battery (LNNB) remains the subject of controversy among neuropsychologists. Substantial criticisms of a theoretical and applied nature have called into question its research basis as a clinical tool. In response to this, Stambrook (1983) has concluded that further research on the LNNB by neuropsychologists is required. The present commentary disputes this need, pointing to the test author's and publisher's primary responsibility for such research. Tests or batteries may be dropped from one's clinical practice without invoking an obligation on the part of neuropsychology.

Brain Damage, Chronic↗
PubMed1984

Failure of nonlinear models of drinking history variables to predict neuropsychological performance in alcoholics.

To test whether the relationship between drinking parameters and cognitive functioning can be visualized as a curvilinear surface (rather than as a line, which more traditional regression equations presuppose), the authors tested 84 recently detoxified and 72 longer-term abstinent alcoholic men with the Halstead-Reitan battery. Quadratic statistical models did not predict test performance in the first group; a few predictions were found in the second. When the multiple correlation was adjusted for number of cases and variables, the "nonlinear" results were statistically no more significant than those of simpler linear models. It is concluded that drinking history does not readily explain cognitive findings among sober alcoholics and that polynomial models can produce inflated correlation coefficients.

Adult↗
PubMed1984

Can neuropsychological tests detect the sites of cerebrovascular stenoses and occlusions?

Conventional neuropsychological data may not mirror the site of cerebrovascular stenosis in a patient with mild to moderate symptoms. In this study, three groups of cerebral revascularization candidates failed to differ on an extended Halstead-Reitan battery: patients with symptoms and angiographic results referable to the carotid arterial system, subjects with clinical signs and neuroradiological findings referable to the vertebrobasilar arterial system, and patients with symptoms of cerebral ischemia but negative angiograms. Consistent with previous work, these patients generally were mildly impaired on neuropsychological tests, even though many were not symptomatic at the time of assessment. Neuropsychological tests seem to be sensitive to the presence and severity of cerebral ischemia, but in isolation may not be sufficient to determine the loci of vascular stenoses. The incongruence between angiographic and neuropsychological findings underlines the importance of distinguishing among different levels and types of measurements in defining subgroups of cerebral revascularization candidates. Collaboration among neuroscientists will further our understanding of the interrelationships among neurodiagnostic tests.

Carotid Artery Diseases↗
PubMed1984

Neurobehavioral deficit and computed tomographic abnormalities in three samples of schizophrenic patients.

Recent reports have suggested that schizophrenics show brain abnormalities as reflected on computed tomography (CT Scan). We present data on three groups of schizophrenic patients which replicate our original report of this phenomenon with associated neuropsychological test results. The over-all evidence for an increased rate of neuropsychological abnormalities and related CT structural anomalies in groups of schizophrenics in several studies is robust. The biological dynamics, cause-effect relationships, and clinical applicability of this phenomenon in the individual case, however, are far from clear. Diagnostic agreements between behavioral and structural abnormalities should simultaneously sound a note of clinical caution and stimulate further study.

Brain Damage, Chronic↗
PubMed1983

Effects of hemodialysis on the cognitive and sensory-motor functioning of the adult chronic hemodialysis patient.

Twenty chronically dialyzed adults were administered a repeatable battery of 14 cognitive and sensory-motor tests on 3 consecutive days: immediately prior to their midweek dialysis, approximately 20 hr after their midweek dialysis, and again immediately prior to their end-of-the week dialysis. Serum electrolyte and methylamine analyses were performed at each test session. When compared to established norms, these patients scored within the normal range in a wide variety of areas. Limited impairments, probably due to peripheral neuropathy, were in evidence on the Grooved Pegboard, Finger Tapping (females), and Grip Strength (females) measures. Impairments suggestive of cerebral dysfunction were also noted on the Benton Visual Retention Test and on the Trail Making Test, Parts A and B, with particularly severe impairment noted on Part B. Despite significant daily changes in serum levels of toxic substances retained in uremia, there was little or no evidence to suggest that well-dialyzed patients undergo daily fluctuations in their cognitive and sensory-motor functioning.

Adult↗
PubMed1983

Psychologic effects of continuous and nocturnal oxygen therapy in hypoxemic chronic obstructive pulmonary disease.

The Nocturnal Oxygen Therapy Trial (NOTT) showed previously that patients with hypoxemic chronic obstructive pulmonary disease (COPD) frequently suffered from neuropsychologic deficit and experienced disturbed mood, personality, and life quality. The present study has followed up 150 NOTT patients six months after they were randomized to continuous oxygen treatment (COT) or nocturnal oxygen treatment (NOT). Tested off oxygen, 42% showed modest neuropsychologic improvement after six months of therapy, and the rates for COT and NOT were comparable. A subsample (n = 37) was examined a third time, after 12 months of treatment. At this point patients receiving COT registered better neuropsychologic performance than those receiving NOT. Concurrently, the COT group began showing improved survival. Despite mild neuropsychologic improvement, patients reported little change in emotional status or life quality. It is concluded that prolonged oxygen treatment is associated with small but definite improvement in brain functioning among patients with hypoxemic COPD, and that COT might have some advantage over NOT in enhancing neuropsychologic functioning as well as survival.

Cognition↗
PubMed1982

Preoperative neurobehavioral impairment in cerebral revascularization candidates.

We examined level of performance in 40 candidates for cerebral revascularization and found substantial variability on general indices of neuropsychological performance. Patients differed by duration of their longest ischemic attack, by surgery type, but not by time since onset of their first ischemic attack. Duration of the longest ischemic attack correlated highly with neuropsychological summary scores. In contrast, symptom duration was unrelated to level of performance in 18 additional patients with histories consistent with cerebrovascular ischemia who did not undergo surgery subsequently. We concluded that initial status on neuropsychological tests is an important variable to consider in postoperative followup of patients undergoing cerebral revascularization. More detailed clinical history and finer grained analysis of neuropsychological data promised to reveal additional relationships among clinical symptoms, neurobehavioral data, and underlying neuropathology.

Brain Ischemia↗
PubMed1982

Life quality of patients with chronic obstructive pulmonary disease.

Two hundred three patients with hypoxemic chronic obstructive pulmonary disease (COPD) and 73 healthy control subjects matched for age, sex, race, and neighborhood of residence were administered three self-report inventories concerned with the following four dimensions of life quality: emotional functioning, social-role functioning, activities of daily living, and recreational pastimes. An additional inventory was administered to a spouse or another close relative of each patient. The life quality of patients with COPD was found to be impaired relative to healthy subjects on all dimensions. Depression was the preponderant emotional disturbance reported; difficulties with home management and reduction in social interaction were the primary social-role deficits. Ambulation, mobility, sleep and rest, and a variety of recreational pastimes were also severely affected. Life quality exhibited moderate but significant relationships to neuropsychological, pulmonary, and cardiac functioning and to exercise capability. Age and socioeconomic status were found to be possible moderators of the relationship of COPD to life quality. A model to integrate these findings is proposed. Implications for the management of COPD and for the evaluation of medical treatments of chronic disabling conditions are described.

Activities of Daily Living↗
PubMed1982

Neuropsychologic findings in hypoxemic chronic obstructive pulmonary disease.

As part of a six-center clinical trial of the effectiveness of continuous v nocturnal oxygen in the management of hypoxemic chronic obstructive pulmonary disease (COPD), we performed detailed neuropsychologic assessments of these patients prior to their beginning treatment. The 203 patients (age, 65 years; Pao2, 51 mm Hg; forced expiratory volume in 1 s, 0.74 L) performed significantly worse than controls on virtually all neuropsychologic tests. Moderate to severe test impairment suggestive of cerebral dysfunction was found in 42% of the patients, as compared with 14% of controls. Higher cognitive functions (abstracting ability, complex perceptual-motor integration) were most severely affected, although half the patients also showed decrements in motor speed, strength, and coordination. Low-order significant inverse correlations were found between neuropsychologic impairment and Pao2, resting arterial oxygen saturation and hemoglobin levels and maximum work. It is concluded that cerebral disturbance is common in hypoxemic COPD and may be related in part to decreased availability of oxygen to the brain.

Adult↗
PubMed1981

Cross-study comparisons of self-reported alcohol consumption in four clinical groups.

Clinical research on the chronic effects of alcohol has been difficult to evaluate and compare because of the failure by investigators to quantify self-reported alcohol consumption. The authors describe four diverse groups of patients who were treated for alcohol and/or drug abuse. After devising a procedure for comparing the data from these studies, they found that patient self-reports of alcohol consumption may be less distorted than commonly assumed. The present findings are consistent with current research indicating that self-reports of alcohol use are reliable and clinically consistent. The authors also discuss the relationship between neuropsychological impairment and measures of alcohol and drug abuse.

Adult↗