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At least 145 records · Page 8Linked to original sources
PubMed2001

[German instrument for the assessment of quality of life in skin diseases (DIELH). Internal consistency, reliability, convergent and discriminant validity and responsiveness].

BACKGROUND AND OBJECTIVE: Performance and psychometric testing of the German Instrument for the Assessment of Quality of Life in Skin Diseases (DIELH). PATIENTS/METHODS: The instrument consisting of 36 questions (maximum skore 180, 7 domains) was used in 836 outpatients and quality assessments (validity, reliability, responsiveness) were performed. RESULTS: The total skore had a mean of 54 pts. (STD 31, range 0-157) and was normally distributed. Women reported a higher impact on quality of life (median 56 vs. 49, p < 0.001). In terms of discriminant validity significant differences between diagnostic groups were observed with high scorings for patients with eczema, psoriasis, urticaria, and acne (p < 0.001). Tests for internal consistency (Cronbach's alpha 0.71-0.92) and reliability (r = 0.73-0.86) revealed valid results. The DIELH correlated well with the DLQI (r = 0.78, p < 0.001) and moderately with 3 domains of the SF 36 (r = 0.25-0.30, p < 0.01). Changes in the quality of life after 4 weeks were consistent with the corresponding changes of the skin condition and partially significant. CONCLUSIONS: In the use within a large patient sample the DIELH proved to be feasible, valid, reliable, and responsive.

Adolescent↗
PubMed1977

The reliability and internal consistency of the motivation rating scale and the general trait rating scale.

The Motivation Rating Scale (MRS) and General Trait Rating (GTRS) Scales have been proposed as methods for assessing personality traits of athletes. The scales are easily accessible and are proposed for use as coaching tools. A coach's form and athlete's form of each test was administered to 149 male and female varsity high school basketball players and their coaches in eight different states. Means and standard deviations for all variables as well as test-retest reliability coefficients, trait inter-correlations, correlations between test forms, and Alpha coefficients were calculated. Results suggest that each of the four scales was independent of the others, with the coach's form of the MRS showing reasonable reliability and reasonable internal consistency for selected traits. There is some indication that "trait generalization" among coaches may inflate the test-retest reliability of the coach's form of the MRS. No convincing evidence is presented to support the notion that any of the four scales measure the traits the scales are purported to measure.

Adolescent↗
PubMed1977

Scales for measuring health belief model dimensions: a test of predictive value, internal consistency, and relationships among beliefs.

Critiques of research on the Health Belief Model have been directed at the need for: (1) applying the Model to behavior related to chronic illness; (2) multivariate testing of the major dimensions of the Model; (3) developing reliable scales; and (4) explicating the relationships among the beliefs. In an attempt to respond to these concerns, data are presented from a prospective study of mothers' adherence to a diet regimen prescribed for their obese children. The Model components were found, both singly and in combination, to be correlated with the study's measure of dietary compliance. Multiple regression analysis utilizing five belief indices accounted for a substantial portion of the variance in children's weight change. Questionnaire items employed in creating indices for each Model dimension are presented, together with discussion of the internal consistency of each index. Belief intercorrelations appear to demonstrate that distinct Model dimensions exist.

Adolescent↗
PubMedDate not supplied

[Factorial structure and internal consistency of the French version of the twenty-item Toronto Alexithymia Scale in a group of 183 healthy probands].

The factorial structure of the French version of the twenty-item Toronto Alexithymia Scale (TAS-20) was studied in a group of 183 healthy subjects. The TAS-20 represents the latest revised version of the TAS. His psychometric characteristics are clearly superior than the others alexithymia scales. Our subjects filled out the TAS whose 14 items are common with the TAS-20. We conducted our statistical analyses on these 14 items. A principal components analysis was carried out and yielded a two-factor solution where the items rating the ability to describe feelings and the items rating the ability to identify feelings constitute one sole factor. The second factor corresponds to the externally oriented factor. The internal consistency of the scale was also measured by the Cronbach alpha coefficient and by the correlation between each item and the total score. The value of the Cronbach alpha was 0.79 and the correlation between each item and the total score ranges from 0.19 (p < 0.05) to 0.69 (p < 0.001) with a mean of 0.52. Our results confirm a previous work on a group of 263 normal students which showed a two-factor solution of the TAS-20. The French version of the TAS-20 seems to be reliable and constitutes a useful instrument to study alexithymia in psychopathology.

Adult↗
PubMed2000

The Morel stereotactic atlas of the human thalamus: atlas-to-MR registration of internally consistent canonical model.

In 1997, Morel, Magnin, and Jeanmonod presented a microscopic stereotactic atlas of the human thalamus. Parcellations of thalamic nuclei did not only use cyto- and myeloarchitectonic criteria, but were additionally corroborated by staining for calcium-binding proteins, which bears functional significance. The atlas complies with the Anglosaxon nomenclature elaborated by Jones and the data were sampled in three orthogonal planes in the AC-PC reference space. We report on the generation of three-dimensional digital models of the thalamus based on the three sets of sections (sagittal, horizontal, and frontal). Spatial differences between the three anatomical specimens were evaluated using the centers of gravity of 13 selected nuclei as landmarks. Subsequent linear regression analysis yielded equations, which were used to normalize the frontal and horizontal digital models to the sagittal one. The outcome is an internally consistent Canonical Model of Morel's atlas, which minimizes the linear component of the variability between the three sectioned anatomical specimens. In addition, we demonstrate the feasibility of the atlas-to-MRI registration in conjunction with on-line visualization of the trajectory in the digital models.

Brain Mapping↗
PubMed2001

The internal consistency and validity of the Self-Assessment Parkinson's Disease Disability Scale.

OBJECTIVE: To test the consistency and validity of the Self-assessment Parkinson's Disease Disability Scale in patients with Parkinson's disease living at home. DESIGN: Patients with Parkinson's disease responded to a set of questionnaires. In addition, an observation of the performance of daily activities was carried out on a subgroup. SETTING AND SUBJECTS: Patients with Parkinson's disease living at home (n = 142). MEASURES: The Self-assessment Parkinson's Disease Disability Scale (SPDDS), the Hoehn & Yahr Rating Scale (H&Y), and the Sickness Impact Profile (SIP68). The observation concerned nine activities that correspond to items of the SPDDS questionnaire. RESULTS: Internal consistency of the SPDDS was very high (Cronbach's alpha = 0.97; reliability rho = 0.97). The items of the SPDDS are hierarchical (Loevinger's H = 0.64): patients had least difficulty with 'washing' and 'brushing teeth' and most difficulty with 'turning in bed', 'travelling by public transport' and 'writing a letter'. Validity of the SPDDS was good: the relationship between the SPDDS questionnaire and the H&Y rating scale, the SIP68 and the results of the observation was strong and significant. CONCLUSION: The SPDDS is a unidimensional instrument measuring disabilities in Parkinson's disease patients living at home.

Activities of Daily Living↗
PubMed2001

Questionnaire-based mechanical exposure indices for large population studies--reliability, internal consistency and predictive validity.

OBJECTIVES: This study attempts to construct valid indices for mechanical exposure of the shoulder-neck region with relation to the development of shoulder-neck pain in a 1-year perspective study of a general population. METHODS: A comprehensive questionnaire was presented to 14 556 subjects aged 45 or 65 years and repeated after 12 months. Twenty-four questions concerning positions, movements, and manual materials handling were registered on a 3-point impact scale. Musculoskeletal problems were reported on a slightly modified version of the Standardized Nordic Questionnaire for the Analysis of Musculoskeletal Symptoms. Test-retest stability after 2 weeks was calculated for 232 consecutive participants. Based on mechanistic theories, 4 exposure indices were formed. Another 5 constructs were obtained by factor analysis. RESULTS: All the indices showed good test-retest stability, and 5 of them had very good internal consistency. Due to overlaps between the indices, 2 indices stood out as having unique properties. One of them concerned mainly postures and the other dealt primarily with measured lifting. However, the latter was not related to the shoulder-neck pain outcome when adjusted for the posture index. The posture index showed an exposure-effect relationship with the outcome. The job titles implied a large degree of exposure misclassification. CONCLUSIONS: The posture index is recommended as a mechanical exposure index for analyses of interaction with other possible determinants of shoulder-neck pain (ie, psychosocial factors). The use of such an index instead of job titles in large population studies will reduce the risk of misclassification.

Analysis of Variance↗
PubMedDate not supplied

Global judgments versus decision-model-facilitated judgments: are experts internally consistent?

A widely used method for evaluating the appropriateness of medical procedures and practices is the "modified Delphi" approach using expert panelists' global ratings. However, several difficulties in the assignment of global ratings have led to a search for alternative methods, including the use of decision models. To examine the potential impact of using decision models with an expert panel, the authors compared a panel's global ratings for the appropriateness of carotid endarterectomy with the results of a decision-analytic model in which expert panelists estimated probabilities and utilities that were used as inputs for the model. For 17 different patient scenarios, the nine expert panelists showed variability in "calibration" between the two methods, with their expected utilities calculated from the model generally being higher than their global ratings. However, the correlation between the two methods was excellent. When the panel's median global utility was compared with the panel's median expected utility calculated from the model, the Spearman correlation coefficient was 0.88. This study demonstrated that an expert panel's appropriateness ratings and their expected utilities were highly correlated. In addition, the panelists appeared to be internally consistent in that their judgments about individual probabilities and utilities were correlated with their global judgments. These results should encourage additional efforts to incorporate decision models into the process of clinical guideline development. The authors believe that decision models can help improve a panel's capacity to understand and reconcile discordance, and increase their satisfaction that the process reflects the best possible judgments.

Carotid Stenosis↗
PubMed2005

Reliability of AOFAS diabetic foot questionnaire in Charcot arthropathy: stability, internal consistency, and measurable difference.

BACKGROUND: The development of Charcot changes is known to be associated with a high rate of recurrent ulceration and amputation. Unfortunately, the effect of Charcot arthropathy on quality of life in diabetic patients has not been systematically studied because of a lack of a disease-specific instrument. The purpose of this study was to develop and test an instrument to evaluate the health-related quality of life of diabetic foot disease. METHODS: Subjects diagnosed with Charcot arthropathy completed a patient self-administered questionnaire, and clinicians completed an accompanying observational survey. The patient self-administered questionnaire was organized into five general sections: demographics, general health, diabetes-related symptoms, comorbidities, and satisfaction. The scales measured the effect in six health domains: 1) general health, 2) care, 3) worry, 4) sleep, 5) emotion, and 6) physicality. The psychometric properties of the scales were evaluated and the summary scores for the Short-Form Health Survey (SF-36) were compared to published norms for other major medical illnesses. RESULTS: Of the 89 enrolled patients, 57 who completed the questionnaire on enrollment returned a second completed form at 3-month followup. Over the 3-month followup period most of the patients showed an improvement in the Eichenholtz staging. The internal consistency of most was moderate to high and, in general, the scale scores were stable over 3 months. However, several of the scales suffered from low-ceiling or high-floor effects. Patients with Charcot arthropathy had a much lower physical component score on enrollment than the reported norms for other disease conditions, including diabetes. CONCLUSIONS: Quality of life represents an important set of outcomes when evaluating the effectiveness of treatment for patients with Charcot arthropathy. This study represents an initial attempt to develop a standardized survey for use with this patient population. Further studies need to be done with larger groups of patients to refine the tool and to begin the validation process. The instrument developed could be used for comparing treatment strategies for Charcot arthropathy.

Adult↗
PubMed1987

Dimensionality, internal consistency and interrater reliability of clinical performance ratings.

A total of 6444 ratings of the financial performance of 424 third- and fourth-year medical students were made by house officers and attending teachers during 12 separate internal medicine rotations. Ratings were based on 13 behaviourally anchored rating scales. One rating was randomly selected per student per evaluator type (house officer and attending teacher) during each of the 12 rotation periods. Ratings were factor analysed separately within each rotation period. Two factors emerged consistently, and congruence coefficients across the 12 occasions were high (0.88 or greater). The factors were labelled 'problem-solving (10 items) and 'interpersonal skills' (three items) on the basis of their content. Internal consistency coefficients of the indices constructed from items in the two factors and the total of the 13 items were high (0.9 or greater) and did not differ substantially when computed separately on the ratings from house officers and attending teachers. Interrater reliabilities on the individual items ranged from 0.14 to 0.33.

Clinical Clerkship↗
PubMed1984

Integrated function of a kinetic proofreading mechanism: steady-state analysis testing internal consistency of data obtained in vivo and in vitro and predicting parameter values.

Experimental measurements of the kinetic mechanism involving isoleucyl-tRNA synthetase proofreading valyl-tRNAIle in Escherichia coli have been incorporated into the conventional Michaelis-Menten model for this system. The model was subjected to a detailed mathematical analysis in the steady state. The results of this analysis provide an excellent illustration of the value of integrating fragmentary data into a model of the intact system. (1) Such integration provides a rigorous test for consistency of the individual measurements. For the above synthetase system, the published experimental data were found to be internally inconsistent. (2) Such integration predicts which experimental data are most suspect. In this case, one of the three most questionable measurements, the isoleucine pool size in vivo, was found upon reexamination to be in error by 10-15-fold. Correction of this error produced a self-consistent set of parameter values. (3) The integrated analysis provides predictions for various parameter values. In many cases, these predictions provide estimates for parameter values that are difficult to determine directly or that have yet to be measured experimentally. (4) A sensitivity analysis provides an indication of the relative importance of various parameter values and, hence, an indication of where future experimental effort might be focused most profitably.

Amino Acyl-tRNA Synthetases↗
PubMed1994

Children of Alcoholics Screening Test: internal consistency, factor structure, and relationship to measures of family environment.

The children of Alcoholics Screening Test (CAST) and the Family Environment Scale were administered to 307 adults (M age = 27.6 years, 81% female, 89% White). Internal reliability estimates of the CAST were high (r = .98). Factor analysis of the CAST resulted in a four-factor solution, which accounted for 67% of the variability-Parental Problem Drinking, Personal Distress, Responsibility for Parental Drinking, and Alcoholic Mother. A canonical correlation between measures of family environment and the CAST factors showed that higher levels of conflict and lower levels of cohesion and expressiveness were stronger predictors of Personal Distress in the child than of Parental Drinking Behavior. The results suggest that distress in children of alcoholics may be more a function of an impaired family than of parental drinking behavior itself.

Adolescent↗
PubMed2000

Internal consistency reliability and validity of the Hebrew translation of the Oxford Happiness Inventory.

The Hebrew translation of the Oxford Happiness Inventory and the short form Revised Eysenck Personality Questionnaire were completed by 298 undergraduate women in Israel. The findings confirm the internal reliability of the Hebrew translation of the Oxford Happiness Inventory and support the construct validity according to which "happiness is a thing called stable extraversion."

Adult↗
PubMed2004

Testing the internal consistency of the standard gamble in 'success' and 'failure' frames.

Decision making behaviour has often been shown to vary following changes in the way in which choice problems are described (or 'framed'). Moreover, a number of researchers have demonstrated that the standard gamble is prone to internal inconsistency, and loss aversion has been proposed as an explanation for this observed bias. This study attempts to alter the influence of loss aversion by framing the treatment arm of the standard gamble in terms of success (where we may expect the influence of loss aversion to be relatively weak) and in terms of failure (where we may expect the influence of loss aversion to be relatively strong). The objectives of the study are (1) to test whether standard gamble values vary when structurally identical gambles are differentially framed, and (2) to test whether the standard gamble is equally prone to internal inconsistency across the two frames. The results show that compared to framing in terms of treatment success, significantly higher values were inferred when the gamble was framed in terms of treatment failure. However, there was no difference in the quite marked levels of internal inconsistency observed in both frames. It is possible that the essential construct of the standard gamble induces substantial and/or widespread loss aversion irrespective of the way in which the gamble is framed, which offers a fundamental challenge to the usefulness of this value elicitation instrument. It is therefore recommended that further tests are undertaken on more sophisticated corrective procedures designed to limit the influence of loss aversion.

Adult↗
PubMed2006

A QSAR model of HERG binding using a large, diverse, and internally consistent training set.

Over the past decade, the pharmaceutical industry has begun to address an addition to ADME/Tox profiling--the ability of a compound to bind to and inhibit the human ether-a-go-go-related gene (hERG)-encoded cardiac potassium channel. With the compilation of a large and diverse set of compounds measured in a single, consistent hERG channel inhibition assay, we recognized a unique opportunity to attempt to construct predictive QSAR models. Early efforts with classification models built from this training set were very encouraging. Here, we report a systematic evaluation of regression models based on neural network ensembles in conjunction with a variety of structure representations and feature selection algorithms. The combination of these modeling techniques (neural networks to capture non-linear relationships in the data, feature selection to prevent over-fitting, and aggregation to minimize model instability) was found to produce models with very good internal cross-validation statistics and good predictivity on external data.

Algorithms↗
PubMed1994

Quality of life in asthma. I. Internal consistency and validity of the SF-36 questionnaire.

Asthma is a chronic disease in which social life is altered. The importance of restrictions on social life may be greater in severe asthma or when symptoms are not adequately controlled. General scales of quality-of-life (QOL) may be used to detect the importance of social life impairment, but it is not yet known whether the scores of such QOL measures are reliable and valid in asthmatic patients. A study was carried out in 252 patients with asthma of variable severity (FEV1 ranging from 25 to 131% of predicted) to assess the validity of a general QOL scale, the first French version of the SF-36 health status questionnaire (SF-36). This is based on 36 items selected to represent nine health concepts (physical, social, and role functioning; mental health; health perceptions; energy or fatigue; pain; and general health). All nine SF-36 category scores were highly significantly correlated with the severity of asthma assessed by the clinical score of Aas (p < 0.0007 to p < 0.0001). Eight SF-36 category scores were highly significantly correlated with FEV1 (p < 0.003 to p < 0.0001). A high internal reliability of SF-36 was found using the alpha coefficient of Cronbach (0.91 for the whole questionnaire). The SF-36 questionnaire is valid and reliable in asthma and can therefore be used to examine QOL in asthmatic and nonasthmatic patients and to determine to what extent asthma impairs social life.

Adult↗
PubMed2001

Psychological reactance: factor structure and internal consistency of the Questionnaire for the Measurement of Psychological Reactance.

Psychological reactance, the theory that people resist attempts to constrain either their thoughts or their behaviors (J. W. Brehm, 1966), has been an influential concept in social psychology. In an attempt to measure reactance, J. Merz (1983) developed the Questionnaire for the Measurement of Psychological Reactance (QMPR). Subsequent researchers (S.-M. Hong & R. Ostini, 1989; R. K. Tucker & P. Y. Byers, 1987) have debated both the exact factor structure and the psychometric stability of the QMPR. In the present study, 898 undergraduates completed the QMPR. Factor analysis suggested that psychological reactance is multidimensional. The authors found 3 factors underlying the QMPR, but the QMPR provided unreliable estimates for each of those factors. According to the results, the QMPR as currently written is psychometrically unsatisfactory.

Adolescent↗