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At least 343 records · Page 19Linked to original sources

Validation of the structure of the perceived meanings of cancer pain inventory.

This study examined the structure of a newly developed instrument measuring the meaning of cancer pain for Taiwanese patients. The Perceived Meanings of Cancer Pain Inventory (PMCPI) was developed based on Lazarus's cognitive theory of emotion and on findings from qualitative interviews. The 27-item PMCPI contains six scales: loss, threat, challenge, blame-others, blame-self, and spiritual awareness. Two hundred cancer patients from three hospitals in northern Taiwan who were experiencing pain were included in the study. A series of confirmatory factor analyses were conducted to test the fit of specified measurement models. The results indicated that only the loss, threat, challenge and spiritual awareness scales possessed good construct validity, while blame-other and blame-self failed to show a satisfactory fit with the data. Correlation coefficients among the scales were also estimated. Parallel-item testing demonstrated that the items of each valid scale had the same factor loading and error variance.

Adult↗

Development and validation of a Structured Telephone Interview for Dementia Assessment (STIDA): the NIMH Genetics Initiative.

As part of the NIMH Genetics Initiative Alzheimer's Disease (AD) Study Group, a brief structured telephone interview to distinguish individuals with normal cognitive functioning from those with changes in cognition and daily functioning suggestive of early AD was developed. The Structured Telephone Interview for Dementia Assessment (STIDA), yields a dementia score between 0 and 81 (higher scores indicating greater impairment). Subscales corresponding to the subscales of the Clinical Dementia Rating Scale (CDR) can be derived. The STIDA performed well as a screening instrument for mildly demented individuals. When a score of 10 or more (based on informant interview and subject testing) was used to identify mildly impaired individuals, the STIDA had a sensitivity of .93 and a specificity of .92 for a clinician-derived CDR of 0.5 or more. The STIDA was also capable of accurately assessing the level of dementia. STIDA-derived CDR ratings agreed with clinician-derived CDR scores in 23 of 28 cases, corresponding to an unweighted kappa of.71 and a weighted kappa of.81. A much-abbreviated short STIDA that could be administered directly to the subject was able to detect possible impairment with a sensitivity of .93 and a specificity of.77. These results suggest that the short STIDA provides a sensitive and fairly specific telephone screen for dementia, and that the full STIDA, consisting of an interview with a knowledgeable informant and subject testing, approximates the success of a face-to-face clinical interview, and provides reliable and valid screening and staging of dementia over the telephone.

Aged↗

Cross-validation of protein structural class prediction using statistical clustering and neural networks.

We present an approach to predicting protein structural class that uses amino acid composition and hydrophobic pattern frequency information as input to two types of neural networks: (1) a three-layer back-propagation network and (2) a learning vector quantization network. The results of these methods are compared to those obtained from a modified Euclidean statistical clustering algorithm. The protein sequence data used to drive these algorithms consist of the normalized frequency of up to 20 amino acid types and six hydrophobic amino acid patterns. From these frequency values the structural class predictions for each protein (all-alpha, all-beta, or alpha-beta classes) are derived. Examples consisting of 64 previously classified proteins were randomly divided into multiple training (56 proteins) and test (8 proteins) sets. The best performing algorithm on the test sets was the learning vector quantization network using 17 inputs, obtaining a prediction accuracy of 80.2%. The Matthews correlation coefficients are statistically significant for all algorithms and all structural classes. The differences between algorithms are in general not statistically significant. These results show that information exists in protein primary sequences that is easily obtainable and useful for the prediction of protein structural class by neural networks as well as by standard statistical clustering algorithms.

Algorithms↗

A closer look at the Autism Behavior Checklist: discriminant validity and factor structure.

The psychometric properties of the Autism Behavior Checklist (ABC; Krug, Arick, & Almond, 1980a, 1980b), a 57-item screening checklist for autism was investigated. Professional Informants completed the ABC on 67 autistic and 56 mentally retarded and learning-disabled children. The autistic children were the total population of autistic children aged 6-15 in two circumscribed suburban and rural regions. Using the total score, the ABC accurately discriminated 91% of the children, with 87% of the autistic and 96% of the nonautistic group correctly classified. Moreover, the accuracy of classification was virtually identical when only the more heavily weighted checklist items were used. A 3-factor model accounted for 32% of the total variance in the checklist. Seventeen items loaded .4 or more on Factor 1, 12 items loaded on Factor 2, and 10 items loaded on Factor 3. The present results fail to provide empirical support for a single unidimensional scale for autism. Also, there is little support for subdividing the checklist into five subscales based on symptom areas.

Adolescent↗

Rapid validation of molecular structures of biological samples by electrospray-mass spectrometry.

A short account is presented of the method of measuring molecular masses (M(r)) of pure biological samples by electrospray ionisation mass spectrometry. It is demonstrated that the technique yields M(r) values with an effective accuracy equal to or better than 0.008% of the calculated M(r), provided that the correct molecular structure is employed in the calculation. It is therefore recommended that this method of measuring M(r)'s should be considered to form an essential part of all studies aimed at elucidating the molecular structure of purified biological macromolecules or for confirming the identity of labelled samples of such molecules.

Animals↗

Identifying lesions on structural brain images--validation of the method and application to neuropsychological patients.

The study of neuropsychological disorders has been greatly facilitated by the localization of brain lesions on MRI scans. Current popular approaches for the assessment of MRI brain scans mostly depend on the successful segmentation of the brain into grey and white matter. These methods cannot be used effectively with large lesions because lesions usually impair segmentation. We propose a novel, fully automated approach for the delineation of brain lesions on MR scans. This method involves comparing a skull stripped, smoothed, unsegmented T1 images to a control group using the general linear model. We tested this method by using images with simulated lesions of different sizes and images containing real lesions from patients with language deficits. We also tested how varying the size of the Gaussian smoothing kernel affects detection. The simulation was informed by findings of a lesion morphological study also presented here. The proposed method detected simulated lesions effectively in the range of 30--90%<normal signal. Smoothing kernels in the range of 8--12 mm resulted in the most accurate lesion detection. Both artificial and real lesions were optimally detected when the results were uncorrected for multiple comparisons at p<.001. This proposed method produced highly satisfactory results and can be used to generate reproducible detection of lesions.

Adult↗

The Cannabis Problems Questionnaire: factor structure, reliability, and validity.

AIM: To develop a multi-dimensional valid and reliable measure of cannabis-related problems. METHOD: The Cannabis Problems Questionnaire (CPQ) was developed from the Alcohol Problems Questionnaire to measure cannabis treatment outcome. The CPQ was administered on two occasions 1 week apart to a stratified sample of adults who had used cannabis at least once in the previous 3 months. Exploratory factor analyses were conducted and the relationship between items of the CPQ and measures of daily use and dependence assessed. The reliability of the CPQ was also assessed using a test-retest and inter-rater reliability methodology. RESULTS: Exploratory factor analyses revealed a three factor solution best described the data accounting for 57% of the variance in the larger item set. The CPQ is highly reliable with test-retest tetrachoric correlations of between 0.92 and 1.00 and inter-rater reliability correlations between 0.74 and 1.00. The total CPQ score classified DSM-IV cannabis dependence with 84% specificity and sensitivity and daily cannabis use with 83% specificity and 55% sensitivity. CONCLUSIONS: The 22-item CPQ is a valid, reliable and sensitive measure of cannabis-related problems for use with clinical and research populations of current cannabis users.

Adolescent↗

Psychometric properties of a quitting time for alcohol questionnaire: factor structure, reliability, and validity.

Research into the dynamics of alcohol use has traditionally focused on etiological factors, particularly on the reasons an individual engages in drinking behaviours. Although reasons for the permanent cessation of drinking have also been well documented, little is known about the reasons for the episodic cessation of alcohol use that is characteristic of nonproblematic drinking patterns. The purpose of the present study was to develop and validate a questionnaire designed to monitor the reasons an individual temporarily stops drinking at the end of a drinking episode. A 23-item Quitting Time for Alcohol Questionnaire (QTAQ) was developed and distributed to a community based sample of 252 participants. Factor analysis revealed three conceptually distinct factors, QTAQ-IS (Internal Status) QTAQ-AA (Avoidance Adherence) and QTAQ-IC (Immediate Context), which accounted for 36.3% of the variance. Cross-validation on a large sample of undergraduate students (N = 479) confirmed the three-factor solution (accounting for 33% of the variance). Cronbach's alpha coefficients for the factors ranged from .74 to .81 for the community sample and from .62 to .78 for the student sample. The validity of the emergent factors was demonstrated by their ability to classify participants according to self-reported alcohol consumption and alcohol dependence criteria, and also by their significant predictive relationship with these criteria. The present findings suggest that the QTAQ is a useful instrument both for research and for use in clinical practice.

Adolescent↗

Reliability, validity and the structure of the General Health Questionnaire in a Chinese context.

The 30-item General Health Questionnaire (GHQ), the 24-item Self-Reporting Questionnaire (SRQ), and a Chinese version of the Minnesota Multiphasic Personality Inventory (MMPI) were administered to 225 English-speaking Chinese. The GHQ was found to have high internal consistency as a scale and to assess 5 dimensions of psychopathology: anxiety, inadequate coping, depression, insomnia, and social dysfunctioning. As a brief screening instrument, it correlated 0.49 with the SRQ. In the 'case-non-case' classification, it yielded a concordance rate of above 75% with the SRQ. Using the MMPI modal profiles derived from classification research as criterion measures, sensitivity, specificity and correct classification rates were above 70%. Implications for future research with the GHQ are discussed.

Adolescent↗

Factor structure and criterion validity of secondary school teacher ratings of ADHD and ODD.

Attention-Deficit Hyperactivity Disorder (ADHD) is currently viewed as a heterogeneous disorder with two factors: inattention and impulsivity-hyperactivity. This conceptualization of ADHD is based primarily on research with children or samples that mix children and adolescents. To examine if the 2-factor ADHD model is appropriate for adolescents and if the ADHD factors are distinct from Oppositional Defiant Disorder (ODD) in adolescents, teacher rating data were collected for 2 samples of adolescents. The results of a confirmatory factor analysis supported the convergent and divergent validity of a model with separate but correlated factors for inattention, impulsivity-hyperactivity, and defiant behavior. Further evidence of construct validity was found when factor scores were examined relative to the criterion variables of academic performance and rule-breaking behavior. The results support the utility of teacher ratings of ADHD and ODD in the assessment of adolescents, and the applicability of the DSM-IV conceptualization of these disorders to adolescents.

Adolescent↗

Construct validity and dimensional structure of the ASIA motor scale.

BACKGROUND/OBJECTIVE: The use of the American Spinal Injury Association (ASIA) motor score as an outcome measure requires metrological study. This paper tests the hypothesis that a more accurate representation of motor function is obtained using separate upper and lower extremity scales rather than combining all 20 key muscle ratings into a single ASIA motor score. METHODS: We analyzed archived data from 6116 ASIA motor scale records extracted from the National Spinal Cord Injury Statistical Center Database. RESULTS: The hypothesis that separate scales more accurately represent motor function than a single motor scale was supported (chi2(difference) = 2596; df=1; P < 0.0001). Two scales account for 87% of the variance, whereas a single scale accounts for only 82%. Lower extremity function is well represented in both solutions; however, upper extremity function is accurately represented only with the use of 2 separate scales. CONCLUSIONS: The use of components of the ASIA standards for other than classification of spinal cord injury needs study. Several lines of study converge to provide strong support for the existence of 2 distinctive dimensions underlying the ASIA motor scale. The use of a single motor score in spinal cord injury research should be questioned and justified to the extent possible. The use of upper and lower extremity scales will lead to a reduction in measurement error when the motor score is used as an outcome measure. The confirmation of 2 separate dimensions underlying the ASIA motor score will enable more accurate representation of motor function in spinal cord injury research.

Adolescent↗

Test-retest reliability and validity of the Structured Interview for Sleep Disorders According to DSM-III-R.

OBJECTIVE: The purpose of this study was to evaluate the reliability of sleep disorder diagnoses in DSM-III-R by using a newly developed interview, the Structured Interview for Sleep Disorders According to DSM-III-R (SIS-D) and to evaluate the concordance between these diagnoses and sleep laboratory data. In addition, the sources of disagreements between two interviewers in the diagnoses given to the same patient were determined. METHOD: Two different interviewers used the SIS-D to diagnose 68 patients with complaints of sleep disorders. The concordance between these interviewers' diagnoses and polysomnographic findings was investigated by using kappa statistics. RESULTS: There were excellent reliabilities for almost all current main diagnostic categories and good concordance between diagnoses made on the basis of the structured interview and polysomnographic data. The main source of disagreement between interviewers was found in the symptom information given by the patient. CONCLUSIONS: These findings provide support for the utility of DSM-III-R sleep disorder diagnoses and for their retention in DSM-IV. These findings also accord well with a recent literature review of the DSM-III-R diagnosis of primary insomnia by the DSM-IV Work Group on Sleep Disorders. The good concordance between interview diagnoses and polysomnographic data suggests that a structured interview such as the SIS-D may be a useful screening instrument. The authors discuss the implications of these findings for the polysomnographic evaluation of chronic insomnia.

Adult↗

Measures of Criminal Attitudes and Associates (MCAA): development, factor structure, reliability, and validity.

Recent meta-analysis has demonstrated that attitudes and associates are among the best predictors of antisocial behavior. Despite this finding, there are few psychometrically developed and validated measures of criminal and antisocial attitudes and associates. This study reviews the theoretical and empirical development of the Measures of Criminal Attitudes and Associates (MCAA), which is composed of two parts. Part A is a quantified self-report measure of criminal friends. Part B contains four attitude scales: Violence, Entitlement, Antisocial Intent, and Associates. The MCAA showed reasonable reliability (internal consistency and temporal stability) and appropriate convergent and discriminant validity. Criterion validity was evidenced in the scale's relationship with criminal history variables, and a factor analysis confirmed the four distinct scale domains.

Adult↗