Latent information in fluency lists predicts functional decline in persons at risk for Alzheimer disease.

OBJECTIVE: We constructed random forest classifiers employing either the traditional method of scoring semantic fluency word lists or new methods. These classifiers were then compared in terms of their ability to diagnose Alzheimer disease (AD) or to prognosticate among individuals along the continuum from cognitively normal (CN) through mild cognitive impairment (MCI) to AD. METHOD: Semantic fluency lists from 44 cognitively normal elderly individuals, 80 MCI patients, and 41 AD patients were transcribed into electronic text files and scored by four methods: traditional raw scores, clustering and switching scores, "generalized" versions of clustering and switching, and a method based on independent components analysis (ICA). Random forest classifiers based on raw scores were compared to "augmented" classifiers that incorporated newer scoring methods. Outcome variables included AD diagnosis at baseline, MCI conversion, increase in Clinical Dementia Rating-Sum of Boxes (CDR-SOB) score, or decrease in Financial Capacity Instrument (FCI) score. Receiver operating characteristic (ROC) curves were constructed for each classifier and the area under the curve (AUC) was calculated. We compared AUC between raw and augmented classifiers using Delong's test and assessed validity and reliability of the augmented classifier. RESULTS: Augmented classifiers outperformed classifiers based on raw scores for the outcome measures AD diagnosis (AUC .97 vs. .95), MCI conversion (AUC .91 vs. .77), CDR-SOB increase (AUC .90 vs. .79), and FCI decrease (AUC .89 vs. .72). Measures of validity and stability over time support the use of the method. CONCLUSION: Latent information in semantic fluency word lists is useful for predicting cognitive and functional decline among elderly individuals at increased risk for developing AD. Modern machine learning methods may incorporate latent information to enhance the diagnostic value of semantic fluency raw scores. These methods could yield information valuable for patient care and clinical trial design with a relatively small investment of time and money.

Lexical factors and cerebral regions influencing verbal fluency performance in MCI.

OBJECTIVE: To evaluate assumptions regarding semantic (noun), verb, and letter fluency in mild cognitive impairment (MCI) and Alzheimer disease (AD) using novel techniques for measuring word similarity in fluency lists and a region of interest (ROI) analysis of gray matter correlates. METHOD: Fifty-eight individuals with normal cognition (NC, n=25), MCI (n=23), or AD (n=10) underwent neuropsychological tests, including 10 verbal fluency tasks (three letter tasks [F, A, S], six noun categories [animals, water creatures, fruits and vegetables, tools, vehicles, boats], and verbs). All pairs of words generated by each participant on each task were compared in terms of semantic (meaning), orthographic (spelling), and phonemic (pronunciation) similarity. We used mixed-effects logistic regression to determine which lexical factors were predictive of word adjacency within the lists. Associations between each fluency raw score and gray matter volumes in sixteen ROIs were identified by means of multiple linear regression. We evaluated causal models for both types of analyses to specify the contributions of diagnosis and various mediator variables to the outcomes of word adjacency and fluency raw score. RESULTS: Semantic similarity between words emerged as the strongest predictor of word adjacency for all fluency tasks, including the letter fluency tasks. Semantic similarity mediated the effect of cognitive impairment on word adjacency only for three fluency tasks employing a biological cue. Orthographic similarity was predictive of word adjacency for the A and S tasks, while phonemic similarity was predictive only for the S task and one semantic task (vehicles). The ROI analysis revealed different patterns of correlations among the various fluency tasks, with the most common associations in the right lower temporal and bilateral dorsal frontal regions. Following correction with gray matter volumes from the opposite hemisphere, significant associations persisted for animals, vehicles, and a composite nouns score in the left inferior frontal gyrus, but for letter A, letter S, and a composite FAS score in the right inferior frontal gyrus. These regressions also revealed a lateralized association of the left subcortical nuclei with all letter fluency scores and fruits and vegetables fluency, and an association of the right lower temporal ROI with letter A, FAS, and verb fluency. Gray matter volume in several bihemispheric ROIs (left dorsal frontal, right lower temporal, right occipital, and bilateral mesial temporal) mediated the relationship between cognitive impairment and fluency for fruits and vegetables. Gray matter volume in the right lower temporal ROI mediated the relationship between cognitive impairment and five fluency raw scores (animals, fruits and vegetables, tools, verbs, and the composite nouns score). CONCLUSION: Semantic memory exerts the strongest influence on word adjacency in letter fluency as well as semantic verbal fluency tasks. Orthography is a stronger influence than pronunciation. All types of fluency task raw scores (letter, noun, and verb) correlate with cerebral regions known to support verbal or nonverbal semantic memory. The findings emphasize the contribution of right hemisphere regions to fluency task performance, particularly for verb and letter fluency. The relationship between diagnosis and semantic fluency performance is mediated by semantic similarity of words and by gray matter volume in the right lower temporal region.

Assessment of knowledge, attitudes, and behaviors relative to cervical cancer and the Pap smear among adolescent girls in West Virginia.

BACKGROUND AND METHODS: Questionnaires assessing knowledge of, attitudes toward, and behaviors relative to cervical cancer and its prevention were administered to 279 tenth-grade girls. RESULTS: Eighty-four percent had heard of cervical cancer, and 83% had heard of the Pap smear. Sexual intercourse with multiple partners and cigarette smoking were risk factors identified by 65% and 40% of these students, respectively. Forty-eight percent reported being sexually active. This group, compared with those not sexually active, was more likely to 1) identify the Pap test as a test involving a vaginal examination, 2) use tobacco products, and 3) be exposed to tobacco smoke. The most common barriers to obtaining a Pap test reported by those sexually active were embarrassment (64%), pain/discomfort (57%), fear of cancer (27%), fear of parents discovering sexual activity (25%), and cost (13%). CONCLUSIONS: Based on the information obtained in this study, the authors recommend changes in school health programs that target adolescent girls: 1) risk factors and behavior should receive more emphasis, and 2) the pelvic examination and Pap test should be described in sufficient detail to address the issues of embarrassment, pain, and discomfort.

Reliability and validity of the Disability Rating Scale and the Levels of Cognitive Functioning Scale in monitoring recovery from severe head injury.

The Disability Rating Scale (DRS) and the Levels of Cognitive Functioning Scale (LCFS) are both widely used to monitor recovery from head injury, despite the total lack of published research on the reliability and validity of the LCFS, and the fragmented and incomplete reports on these characteristics of the DRS. Forty head-injured inpatients were evaluated with the DRS and LCFS four times weekly throughout their rehabilitation hospitalization. The DRS and LCFS were compared in terms of how consistently ratings could be made by different raters, how stable those ratings were from day to day, their relative correlation with Stover Zeiger (S-Z) ratings collected concurrently at admission, and with S-Z, Glasgow Outcome Scale (GOS), and Expanded GOS (EGOS) ratings collected concurrently at discharge, and finally in the ability of admission DRS and LCFS scores to predict discharge ratings on the S-Z, GOS, and EGOS. Results suggest that both scales possess significant degrees of test-retest and interrater reliabilities, and of concurrent and predictive validities, but the DRS surpasses the LCFS in nearly every regard. These results offer psychometric justification favoring the use of the DRS for monitoring recovery from head injury.

Sex differences in visual information processing following right cerebrovascular accidents.

This study examined whether males and females who had sustained right CVA's but did not show gross asymmetries in processing left- and right-sided visual information would demonstrate visual hemiimperception when tested with more demanding evaluation procedures. Testing involved tasks of reaction time, oral reading and searching for embedded words and figures. Males and females differed in their response patterns for tasks involving searching for embedded target stimuli; specifically, males required greater lengths of time to locate stimuli in left hemispace, while females showed no such pattern of results. This suggests that closer attention must be paid to screening procedures used to detect hemispatial visual imperceptions, particularly among males.

Dependent variables in rehabilitation research.

It is important that rehabilitation professionals use appropriate techniques to evaluate their treatments. False, contradictory, diverse, and misleading interpretations can be obtained depending on how dependent variables in treatment outcome research are quantified. This report describes an evaluation of a single-subject investigation that used a push-up timer for teaching pressure relief maneuvers. Results are analyzed four separate ways, and can be taken to support three quite different conclusions. This illustrates that investigators should carefully select procedures of analysis before initiating a study to avoid having to make a post hoc and potentially biased selection of which mode(s) of data analysis and presentation is most appropriate. However, such an a priori selection of analysis does not relieve investigators of the responsibility for analyzing their data from different perspectives and discussing alternate or contradictory interpretations.

Behavior modification in physical therapy.

Behavioral techniques reported to improve ambulation skills among physically handicapped persons include both reward and desensitization procedures. This report describes the application of other behavior modification principles to two patients who resisted physical therapy (PT) designed to educate them in the use of orthopedic assistive devices. Peer modeling was used with case 1, a 2 1/2-year-old girl with complete L4 spina bifida who cried frequently when wearing her brace, and refused to walk except with much assistance. Case 2 was a 21-year-old hemiplegic man seen two years after a severe head injury. Initially, severe tantrum behavior accompanied all demands placed on him. Treatment involved a combination of contingent music for being quiet and contingent aversive auditory feedback for yelling. In both cases clinically significant behavioral changes were observed. Results are discussed with respect to the cost effectiveness of behavioral interventions and the interdisciplinary coordination of rehabilitation team members.