PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Internal validation”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,441 records · Page 80Linked to original sources
PubMed2000

The stroke impairment assessment set: its internal consistency and predictive validity.

OBJECTIVE: To study the scale quality and predictive validity of the Stroke Impairment Assessment Set (SIAS) developed for stroke outcome research. DESIGN: Rasch analysis of the SIAS; stepwise multiple regression analysis to predict discharge functional independence measure (FIM) raw scores from demographic data, the SIAS scores, and the admission FIM scores; cross-validation of the prediction rule. SETTING: Tertiary rehabilitation center in Japan. PATIENTS: One hundred ninety stroke inpatients for the study of the scale quality and the predictive validity; a second sample of 116 stroke inpatients for the cross-validation study. MAIN OUTCOME MEASURES: Mean square fit statistics to study the degree of fit to the unidimensional model; logits to express item difficulties; discharge FIM scores for the study of predictive validity. RESULTS: The degree of misfit was acceptable except for the shoulder range of motion (ROM), pain, visuospatial function, and speech items; and the SIAS items could be arranged on a common unidimensional scale. The difficulty patterns were identical at admission and at discharge except for the deep tendon reflexes, ROM, and pain items. They were also similar for the right- and left-sided brain lesion groups except for the speech and visuospatial items. For the prediction of the discharge FIM scores, the independent variables selected were age, the SIAS total scores, and the admission FIM scores; and the adjusted R2 was .64 (p < .0001). Stability of the predictive equation was confirmed in the cross-validation sample (R2 = .68, p < .001). CONCLUSIONS: The unidimensionality of the SIAS was confirmed, and the SIAS total scores proved useful for stroke outcome prediction.

Adult↗
PubMed2006

The convergent and discriminant validity of burnout measures in sport: a multi-trait/multi-method analysis.

Athlete burnout research has been hampered by the lack of an adequate measurement tool. The Athlete Burnout Questionnaire (ABQ) and the Maslach Burnout Inventory General Survey (MBI-GS) are two recently developed self-report instruments designed to assess burnout. The convergent and discriminant validity of the ABQ and MBI-GS were assessed through multi-trait/multi-method analysis with a sporting population. Overall, the ABQ and the MBI-GS displayed acceptable convergent validity with matching subscales highly correlated, and satisfactory internal discriminant validity with lower correlations between non-matching subscales. Both scales also indicated an adequate discrimination between the concepts of burnout and depression. These findings add support to previous findings in non-sporting populations that depression and burnout are separate constructs. Based on the psychometric results, construct validity analysis and practical considerations, the results support the use of the ABQ to assess athlete burnout.

Adolescent↗
PubMed2000

Internal consistency and concurrent validity of two short forms of the Visual Form Discrimination Test.

The purpose of this study was to evaluate the reliability and concurrent validity of 2 short forms of the Visual Form Discrimination Test, referred to as first half (FH) and front-back (FB). Participants were a mixed sample of 225 patients seen for neuropsychological evaluations. The mean difference score between both short forms and the full form was less than 1 point. The short-total correlations were .85 and .86 for the FH and FB forms, respectively. A binary clinical decision rule, used to classify patients as normal or impaired, resulted in a 93.3% correct and a 94.7% correct classification rate for the FH and FB forms, respectively. It is concluded that the short form of the test, used in conjunction with a clinical decision rule, results in a very minor loss of accuracy.

Adult↗
PubMed2001

Validation of the inflammatory bowel disease questionnaire in Swedish patients with ulcerative colitis.

BACKGROUND: The Inflammatory Bowel Disease Questionnaire (IBDQ) is a disease-specific health-related quality of life (HRQOL) questionnaire including four dimensions and a sum score. The aim of this study was to assess the internal and external validity, reliability, and sensitivity of a Swedish version of the IBDQ. METHODS: Three hundred consecutive patients with ulcerative colitis completed the IBDQ and three other health-related quality of life questionnaires (the Rating Form of IBD Patient Concerns (RFIPC), the Short Form-36 (SF-36) and the Psychological General Well-Being (PGWB) index). Disease activity was evaluated using a 1-week symptom diary, blood tests and rigid sigmoidoscopy. One hundred and fourteen patients filled in the questionnaire a second time, of whom 75 had been in stable remission for over 6 months and 39 had a significant clinical change in disease activity. RESULTS: Factor analysis of the 32 IBDQ items did not support the four dimensional scores. The dimensional scores had sufficient convergent validity, but low discriminative validity and homogeneity. The homogeneity was also low for the sum score. The inter-dimensional correlations were high. The concurrent validity was supported by correlations between the dimensional scores and other measures of disease activity and HRQOL. Patients in relapse scored significantly less on the sum score and the four dimensions compared to patients in remission. The test-retest correlations for the dimensional scores were 0.40-0.76. Patients with a change in disease activity during the 6-month follow-up period had a significant change in IBDQ scores not found in those who remained in remission. CONCLUSIONS: The Swedish version of the IBDQ had external validity and was shown to be a reliable and sensitive measure of HRQOL in ulcerative colitis, though there are some concerns regarding the internal validity. The use of a sum score was not supported and the questionnaire may benefit from a redivision of items into dimensions with better homogeneity and discriminative validity.

Colitis, Ulcerative↗
PubMed2000

Internal quality control in virology: validation of immunoassays using a personal computer spreadsheet.

Design of a spreadsheet to evaluate the performance of internal quality control sera used for the validation of immunoassays in virology is described. Developed using Microsoft Excel 97, it can set target limits and analyse control data by application of Westgard quality control rules. It also provides a permanent record of all relevant information concerning each assay run, including action taken to rectify unacceptable performance.

Humans↗
PubMed2002

Validation of methyl malondialdehyde as internal standard for malondialdehyde detection by capillary electrophoresis.

The aim of this study was to validate, by capillary electrophoresis, the use of synthesized methyl malondialdehyde as the internal standard for the direct quantification of free and total (free+bound) malondialdehyde in biological samples. All analyses were performed in 20 cm x 50 microm uncoated capillaries at 20 degrees C, using 25 mmol/L borax (pH 9.3) and 5 mmol/L tetradecyltrimethylammonium bromide as running buffer. The applied voltage was -4kV (about 8 microA), the detector being set at 260 nm for a total run time of 8 min per sample. Free malondialdehyde was evaluated after acetonitrile extraction, while the samples evaluated for total malondialdehyde were, before extraction, hydrolyzed for 1h at 60 degrees C in the presence of 1 mol/L NaOH. The detection threshold was 0.2 micromol/L in microsomes and 0.4 micromol/L in plasma. As an application of the method, three pools of rat liver microsomes were quantified before (0.35+/-0.1 and 1.1+/-0.5 nmol/mg protein, free and total malondialdehyde, respectively, mean+/-SD) and after lipoperoxidation induction using systems able to generate oxygen free radicals (18.4+/-3.2 and 19.7+/-2.0 nmol/mg protein). The results were confirmed by isotopic dilution gas chromatography-mass spectrometry, used as the reference method. The feasibility of capillary electrophoresis for malondialdehyde determination in normal and pathological human plasma was also investigated.

Acetonitriles↗
PubMed2007

Development and external validation of an extended repeat biopsy nomogram.

PURPOSE: We hypothesized that the outcome of repeat biopsy could be accurately predicted. We tested this hypothesis in a contemporary cohort from 3 centers. MATERIALS AND METHODS: The principal cohort of 1,082 men from Hamburg, Germany was used for nomogram development as well as for internal 200 bootstrap validation in 721 and external validation in 361. Two additional external validation cohorts, including 87 men from Milan, Italy and 142 from Seattle, Washington, were also used. Predictors of prostate cancer on repeat biopsy were patient age, digital rectal examination, prostate specific antigen, percent free prostate specific antigen, number of previous negative biopsy sessions and sampling density. Multivariate logistic regression models were used to develop the nomograms. RESULTS: The mean number of previous negative biopsies was 1.5 (range 1 to 6) and the mean number of cores at final repeat biopsy was 11.1 (range 10 to 24). Of the men 370 (30.2%) had prostate cancer. On multivariate analyses all predictors were statistically significant (p < or =0.028). After internal validation the nomogram was 76% accurate. External validation showed 74% (Hamburg), 78% (Milan) and 68% (Seattle) accuracy. CONCLUSIONS: Relative to the previous nomograms (10 predictors or 71% accuracy) our tool relies on fewer variables (6) and shows superior accuracy in European men. Accuracy in American men is substantially lower. Racial, clinical and biochemical differences may explain the observed discrepancy in predictive accuracy.

Adult↗
PubMed2006

The eating disorder belief questionnaire: psychometric properties in an adolescent sample.

The current study aimed to investigate the psychometric properties of the Eating Disorder Belief Questionnaire in older adolescent females. Three hundred and sixty-seven girls aged 17 or 18 who were in secondary school education completed the Eating Disorder Belief Questionnaire, the Beck Depression Inventory and the Eating Attitudes Test. They also provided information on height and weight. The Eating Disorder Belief Questionnaire had an almost identical factor structure to that previously found in adult women, although the factors were not quite as discrete as those in the original validation study. Internal consistency for each factor was high and construct validity (including convergent and criterion related validity) was very good. The almost identical factor structure, and other good psychometric properties, found for the Eating Disorder Belief Questionnaire in the current study suggests that it is an appropriate measure for use in clinical settings and in research studies involving 17-18 year old girls. This includes older adolescents with eating disorders. The possibility that adolescents show a developmental tendency for less separation between the constructs assessed, when compared with adults, is of particular interest, and requires further exploration.

Adolescent↗
PubMed1998

Quality of life in irritable bowel syndrome, effect of therapy.

BACKGROUND: Irritable bowel syndrome (IBS) is a common disease in the general population. Evaluation of IBS symptoms does not cover all the complaints of patients who report restrictions to social life, the need to diet and psychosocial repercussions. Quality of life (QOL) measurement permits a precise approach to patient status. METHODS: The generic QOL questionnaires SF 36 and two validated specific QOL questionnaires--IBSQOL and Functional Digestive Disorders FDDQL--have been used for the evaluation of IBS patient outcome. IBSQOL measures 9 domains and its reliability and validity have been demonstrated. FDDQL measures 8 domains, an international psychometric validation was obtained in French, English and German by comparison with the SF36. The discriminant validity and responsiveness of the FDDQL have been evaluated. RESULTS: Generic QOL evaluation and specific questionnaires like the FDDQL were able to measure changes in IBS patient status and QOL during several clinical trials. CONCLUSION: Specific QOL questionnaires have been validated in IBS patients and are available for controlled studies. Development of effective new drugs are needed for IBS treatment, complete and precise evaluation of outcome will involve QOL analysis in association with specific validated questionnaires.

Activities of Daily Living↗
PubMed1991

The SPQ: a scale for the assessment of schizotypal personality based on DSM-III-R criteria.

Existing self-report measures of schizotypal personality assess only one to three of the nine traits of schizotypal personality disorder. This study describes the development of the Schizotypal Personality Questionnaire (SPQ), a self-report scale modeled on DSM-III-R criteria for schizotypal personality disorder and containing subscales for all nine schizotypal traits. Two samples of normal subjects (n = 302 and n = 195) were used to test replicability of findings. The SPQ was found to have high sampling validity, high internal reliability (0.91), test-retest reliability (0.82), convergent validity (0.59 to 0.81), discriminant validity, and criterion validity (0.63, 0.68), findings which were replicated across samples. Fifty-five percent of subjects scoring in the top 10 percent of SPQ scores had a clinical diagnosis of schizotypal personality disorder. Thus, the SPQ may be useful in screening for schizotypal personality disorder in the general population and also in researching the correlates of individual schizotypal traits.

Affective Symptoms↗
PubMed2004

The cross-cultural adaptation of the Work Role Functioning Questionnaire in Canadian French.

The Work Role Functioning Questionnaire (WRFQ) is a new work disability measurement tool assessing the perceived impact of a health problem on the worker's ability to perform his job. The objective of this study was to make the cross-cultural adaptation of the WRFQ for the French Canadian population. The methodology was composed of five steps: forward translation, synthesis of the translations, back translation, revision by an expert committee and test of the pre-final version. The psychometric properties of the translated version were evaluated by administering the questionnaire to forty workers with a musculoskeletal disorder (MSD). Results indicated good content validity and internal consistency (Cronbach alpha > 0.80 for each scale). Construct validity was tested and confirmed through three hypotheses: (1) subjects with MSD scored higher for the Physical, Work Scheduling and Output demands scales than for the Mental and Social demands scales, (2) subjects having back pain had lower scores than subjects having pain at other body sites and (3) subjects with an MSD had lower scores than healthy workers working full time. This study confirmed that the process used for the adaptation of the Canadian French version of the WRFQ was successful and that this version had good psychometric properties.

Adult↗
PubMed2005

Cross-cultural validation of the St. Louis Inventory of Community Living Skills for Chinese patients with schizophrenia in Hong Kong.

AIM: The study validated a culturally sensitive community living skills rating scale for Chinese patients by adapting the St. Louis Inventory of Community Living Skills (SLICLS). METHOD: The Chinese version (SLICLS-C) was produced by forward and backward translation. An expert panel evaluated its content validity. Its internal consistency, inter-rater reliability, construct and concurrent validity were tested on 80 DSM-IV schizophrenia inpatients in a long-term facility. For predictive validity, the above sample was extended to ensure at least 20 subjects discharged to each of three levels of community care were included in the study sample. RESULTS AND CONCLUSION: The SLICLS-C was psychometrically sound and could be used for predicting level of community care, program evaluation and measuring outcome.

Activities of Daily Living↗
PubMed2002

[Development of a dispositional version of the General Coping Questionnaire (GCQ) and examination of its reliability and validity].

OBJECTIVE: The purpose of the present study was to develop a dispositional version of a stress coping scale (the General Coping Questionnaire, GCQ), especially for university students, and examine its reliability and validity. METHODS: In Studies I to IV, 124, 784, 83, 83 university students respectively completed the dispositional version of the GCQ. The questionnaire has four subscales covering emotion expression, emotional support seeking, cognitive reinterpretation, and problem solving, with a five-point Likert format. In Study IV, in addition to the dispositional version of the GCQ, peer rating was also performed to test the validity. RESULTS: In Study I, 32 items were selected as a second version of the scale, reducing from the first version with 54 items. From Studies II to IV, evidence was obtained for the factorial validity, the internal consistency, the test-retest reliability, the construct validity (except cognitive reinterpretation), and the normal distribution of the scores. CONCLUSIONS: Standardization of the dispositional version of the GCQ with four subscales was essentially completed, facilitating future studies on coping with stress.

Adaptation, Psychological↗