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PubMed2005

Moroccan colloquial Arabic version of the Mini International Neuropsychiatric Interview (MINI): qualitative and quantitative validation.

The validation of mini international neuropsychiatric interview (MINI) into Moroccan Colloquial Arabic language demonstrated good psychometric properties. The concordance between translated MINI's and expert diagnoses was good with kappa values greater than 0.80. The reliability inter-rater and test-retest were excellent with kappa values above 0.80 and 0.90, respectively.

Arabs↗
PubMed1999

Validation of the Rockall risk scoring system in upper gastrointestinal bleeding.

BACKGROUND: Several scoring systems have been developed to predict the risk of rebleeding or death in patients with upper gastrointestinal bleeding (UGIB). These risk scoring systems have not been validated in a new patient population outside the clinical context of the original study. AIMS: To assess internal and external validity of a simple risk scoring system recently developed by Rockall and coworkers. METHODS: Calibration and discrimination were assessed as measures of validity of the scoring system. Internal validity was assessed using an independent, but similar patient sample studied by Rockall and coworkers, after developing the scoring system (Rockall's validation sample). External validity was assessed using patients admitted to several hospitals in Amsterdam (Vreeburg's validation sample). Calibration was evaluated by a chi2 goodness of fit test, and discrimination was evaluated by calculating the area under the receiver operating characteristic (ROC) curve. RESULTS: Calibration indicated a poor fit in both validation samples for the prediction of rebleeding (p<0.0001, Vreeburg; p=0.007, Rockall), but a better fit for the prediction of mortality in both validation samples (p=0.2, Vreeburg; p=0.3, Rockall). The areas under the ROC curves were rather low in both validation samples for the prediction of rebleeding (0.61, Vreeburg; 0.70, Rockall), but higher for the prediction of mortality (0.73, Vreeburg; 0.81, Rockall). CONCLUSIONS: The risk scoring system developed by Rockall and coworkers is a clinically useful scoring system for stratifying patients with acute UGIB into high and low risk categories for mortality. For the prediction of rebleeding, however, the performance of this scoring system was unsatisfactory.

Adolescent↗
PubMedDate not supplied

Validity and reliability: part I.

Internal and external validity of a study determine the generalizability of its findings. Measurement reliability and validity, which also have an impact on the overall validity of the study, will be discussed in the next column. Although the concepts have been pulled apart for this discussion, all of these factors influence the overall confidence with which researchers can say that they have measured what was intended and that the findings can be applied to a larger population of individuals.

Humans↗
PubMed1996

Short-form alternatives to the Judgment of Line Orientation Test.

The Judgment of Line Orientation Test (JLO; Benton, Hamsher, Varney, & Spreen, 1983) is frequently used as a motor-free method of evaluating visuospatial processing but can be time-consuming to administer. We investigated the internal consistency, validity, and utility of two parallel JLO short forms in a mixed clinical sample of 386 patients. Mean scores were equivalent, and correlational analyses supported the internal consistency and validity of both short forms. When compared to the standard JLO, the odd- and even-item short forms demonstrated good sensitivity, specificity, overall hit rate and predicted positive and negative accuracy. We conclude that the JLO short forms possess sufficient internal consistency, validity, and utility for serial assessment in research studies. The JLO short forms may potentially be used in clinical screening situations by applying a single cut-off score to differentiate levels of performance. However, more detailed clinical use of these JLO short forms will necessitate collection of normative data in order to generate accurate percentile rankings.

Adolescent↗
PubMed2002

Adaptation and validation of the Turkish version of the Rheumatoid Arthritis Quality of Life Scale.

OBJECTIVE: The aim of this study was to adapt the Rheumatoid Arthritis Quality of Life (RAQoL) questionnaire for use in Turkey and to test its reliability and validity. METHODS: The translation process included the recent guidelines for cross-cultural adaptation. Reliability of the Turkish RAQoL was assessed by internal consistency and test-retest reliability, internal construct validity by Rasch analysis, and external construct validity by associations with impairments, disability, and general health status. Cross-cultural validity was tested through analysis of differential item functioning (DIF) by comparison with data from the UK version of the RAQoL. RESULTS: Reliability of the adapted version was good, with high internal consistency (Cronbach's alpha 0.95 and 0.96 at times 1 and 2, respectively) and test-retest reliability (Spearman's rho 0.874). Internal construct validity was confirmed by excellent fit to the Rasch model (mean item fit 0.236, SD 1.113) and external construct validity by expected associations. The DIF for culture was found in four items. CONCLUSIONS: Adaptation of the RAQoL for use in Turkey was successful. The instrument can be used in both national and international studies for cross-cultural comparison with the UK, as long as adjustments are made for the few items displaying DIF for culture.

Aged↗
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↗
PubMed2005

Once-a-day extended-release dosage form of divalproex sodium III: development and validation of a Level A in vitro-in vivo correlation (IVIVC).

Defining a quantitative and reliable relationship between in vitro drug release and in vivo absorption is highly desired for rational development, optimization, and evaluation of controlled-release dosage forms and manufacturing process. During the development of a once-daily extended-release (ER) tablet of divalproex sodium, a predictive in vitro drug release method was designed and statistically evaluated using three formulations with varying release rates. In order to establish an internally and externally validated Level A IVIVC, a total of five different ER formulations of divalproex sodium were used to evaluate a linear IVIVC model based on the in vitro test method. For internal validation, a single-dose four-way crossover study (N = 16) was performed using fast-, medium-, and slow-releasing ER formulations and a 12-h IV infusion of valproic acid as reference. To validate the IVIVC externally, a second three-way crossover study (N = 36) was performed using slightly-fast-, medium-, and slightly-slow-releasing ER formulations. The in vivo absorption-time profile was inferred by deconvolution of the observed plasma concentration-time profiles against the unit disposition function (UDF). A linear IVIVC model was established in which the in vivo absorption was expressed as a function of in vitro drug release. Plasma profiles of ER formulations were estimated via convolution of in vitro release profiles with the UDF. Successful internal and external validations of the model were demonstrated by individual and average absolute percent prediction errors of </=9% for both C(max) and AUC(infinity). In conclusion, a Level A IVIVC describing the entire time-course of plasma concentrations was developed and validated, both internally and externally, for ER formulations of divalproex sodium.

Adolescent↗
PubMed1998

The index of self-regulation: development and psychometric analysis.

This paper describes the development and initial psychometric evaluation of a measure of individual self-regulation in the maintenance of health behavior change. Items were developed from inductively generated data to index dimensions of self-regulation in behavioral change (Fleury, 1991). Quantification of Index of Self-Regulation (ISR) content validity was supported through the ratings of 10 experts, following criteria established by Imle and Atwood (1988). The instrument was tested in successive steps with 146 individuals who were participating in an outpatient cardiac rehabilitation program for reliability and validity, including internal consistency reliability and three forms of validity assessment (content validity, criterion-related validity, and construct validity). The three subscales of Stimulus Control, Reconditioning, and Behavioral Monitoring demonstrated internal consistency ranging from .73-.76. Total scale alpha was .87. Initial estimates of criterion-related and construct validity were documented with correlations between ISR subscales and theoretically related criterion measures (.20-.47). With refinement the ISR will provide a basis for tailoring and evaluating clinical interventions designed to enhance motivation in the maintenance of health behavior change.

Adult↗
PubMed2004

Validation of the Tunisian version of the Roland-Morris questionnaire.

Our aim was to validate a culturally adapted, Tunisian-language version of the Roland-Morris Disability Questionnaire (RMDQ), which is a reliable evaluation instrument for low-back-pain disability. A total of 62 patients with low back pain were assessed by the questionnaire. Reliability for the 1-week test/re-test was assessed by a construction of a Bland Altman plot. Internal construct validity was assessed by Cronbach's alphatest. External construct validity was assessed by association with pain, the Schober test and the General Function Score. Sensitivity to change was determined using a t-test for paired data to compare RMDQ scores at inclusion and at completion of the therapeutic sequence of local corticosteroid injections. We also compared the questionnaire score with the General Function Score, both taken after completion of the therapeutic sequence. The constructed Bland Altman plot showed good reliability. Internal consistency of the RMDQ was found to be very good and the Cronbach's alpha test was 0.94, indicating a good internal construct validity. The questionnaire is correlated with the pain visual analogue scale (r=33; p=0.0001), with the Schober test (r=0.27; p=0.0001) and the General Function Score (r=56; p=0.0001) indicating an adequate external construct validity. The RMDQ administered after the therapeutic sequence is sensitive to change (r=0.83; p=0.000). Comparison of the questionnaire score to the General Function Score, after completion of the therapeutic sequence, was satisfactory (r=0.75; p=0.000). We conclude that the Tunisian version of the Roland-Morris questionnaire has good reliability and internal consistency. Furthermore, it has a good internal- and external construct validity and high sensitivity to change. It is an adequate and useful tool for assessing low-back-pain disability.

Disability Evaluation↗
PubMed2000

Evaluation of the validity of the 1997 International Union Against Cancer TNM classification of major salivary gland carcinoma.

BACKGROUND: The TNM classification (International Union Against Cancer) of salivary gland carcinoma was revised in 1997. In this study, the authors have evaluated the validity of this new TNM classification and clinical staging in 1683 patients with parotid gland carcinoma. METHODS: Reclassification was conducted according to the new classification based on the clinical data of 1683 patients registered to the salivary gland division of the Japanese Joint Committee on TNM classification. The 5- and 10-year survival rates according to TNM classification were calculated for 1074 patients whose prognosis could be followed up. Finally, the distribution of the total patient population was analyzed using the new staging and the survival curves for each disease stage. RESULTS: The variance of the patients for T1 to T4 was appropriate using the new T classification. The 5- and 10-year survival rates corresponded well to the degree of progression of TNM. However, there were only nine patients with Stage III, and marked nonuniformity in the staging was observed. The separation of the survival curves for each stage was not clear, and no significant differences between the survival curves of Stages II and III and Stages III and IV were observed. When the authors classified T1N1M0, T2N1M0, T3N1N0, and T4N0M0, which have 5- and 10-year survival rates similar to Stage III, distribution of patients and separation of the survival curves in each stage improved markedly. CONCLUSIONS: The results of the current study confirm that the new TNM classification system is valid. However, a significant problem was observed with respect to the new clinical staging. The authors propose that T1N1M0, T2N1M0, T3N1M0, and T4N0M0 be classified as Stage III.

Disease-Free Survival↗
PubMed2000

[The internal consistency and content validity of the Spanish version of the Asthma Autonomy Questionnaire].

The Asthma Autonomy Questionnaire (AAQ) was designed to evaluate asthmatics' desire to learn about their disease and to make decisions. The AAQ consists of 26 items distributed in two scales: Preferences in the Search for Information (PSI, 8 items) and Preferences in Decision Making (PDM, 6 general items and 12 related to 3 scenarios depicting asthma in stable phase, during mild exacerbation and during severe exacerbation). The aim of this study was to analyze the internal consistency (Cronbach's-coefficient) and content validity (factorial analysis of principal components) of the AAQ. After translation and back translation, the Spanish version of the AAQ was administered to 115 adult asthmatics of both sexes and differing levels of severity. The alpha coefficients for the two scales and 3 scenarios ranged from 0.42 (PSI) to 0.73 (stable phase scenario); only for the stable-phase scenario were values high or statistically acceptable. Factorial analysis reproduced the content of the scales only approximately, with some items proving to relate to factors that were different from the scale they originally belonged to. These results indicate that, in its current formulation, the AAQ presents important measurement problems and revision is advisable.

Adult↗
PubMed1998

Screening of depression in patients with chronic medical diseases in a primary care setting.

BACKGROUND: Patients with chronic medical diseases may have depression that is not recognized by their primary care physicians. OBJECTIVES: We aimed to examine the application of Zung's Self-Rating Depression Scale (SDS) in the screening of depression in primary care patients with chronic medical diseases in a Chinese population. METHODS: We studied 268 patients with chronic medical diseases in the Family Medicine Outpatient Clinic using a structured questionnaire including basic demographic data, a Chinese version of the SDS and a rating for the self-perceived severity of physical condition. The severity of chronic medical diseases was assessed by the authors using the Duke University Severity of Illness Scale from a chart audit. Fifty patients were randomly selected for a diagnostic interview according to the DSM-IV criteria. The construct validity and internal consistency reliability, sensitivity and specificity of the SDS were examined. RESULTS: The results revealed that the SDS has good construct validity and internal consistent reliability in the evaluation of depression in Chinese patients with chronic medical diseases. A cut-off point of 55 had a sensitivity of 66.7% and a specificity of 90.0%. Depressed patients reported more cognitive symptoms than depressed affect and physical symptoms. Female patients had more severe depressed affect than male patients, but males had more prominent diurnal variation of mood than females. CONCLUSIONS: We concluded that SDS can be a good screening tool for depression in Chinese patients with chronic medical diseases. Owing to constraints in the expression of sexual desire in the Chinese, elderly subjects tended to report loss of libido in the response to the SDS.

Adult↗
PubMed2005

Diagnostic model for sensitization in workers exposed to occupational high molecular weight allergens.

BACKGROUND: Occupational allergy has great impact on workers exposed to high molecular weight (HMW) allergens. The present study is aimed to develop and validate a generic diagnostic model for sensitization to HMW allergens, defined as positive IgE. METHODS: The model was developed in pooled data from Dutch laboratory animal (LA) workers and bakers using logistic regression analysis. Validity was assessed internally by bootstrapping procedure, and externally in British LA workers. RESULTS: The model included working hours/week, work-related symptoms, total IgE, and IgE to common allergen. Significant interactions between the type of work and the predictors resulted in different scores for LA workers and bakers. Internal and external validation showed that the model was satisfactorily calibrated and discriminated between workers at high and low risk of being sensitized. CONCLUSIONS: It is possible to develop a generic model for sensitization to occupational HMW allergens. However, the weighing of predictors differs across specific work environments.

Adult↗
PubMed2006

Validation of a comprehensive classification tool for treatment-related problems.

OBJECTIVE: Several drug-related problem classification systems can be found in the literature. However, it is generally agreed that a comprehensive, well constructed and validated instrument is currently lacking. The aim of this study is the development and validation of a comprehensive treatment-related problems assessment and classification tool for use in teaching, practicing and researching pharmaceutical care and to improve identification, resolving and preventing of treatment-related problems. METHOD: The development and validation involved five steps starting with literature search to define a treatment related problem and also to form a database of treatment-related problems identified in the literature. In the next step, all problems that were identified in the first step and passed the evaluation of the three authors were pooled together and then divided into groups according to their common or shared construct, in the third step a suitable assessment method was developed according to the construct of the different problems, in the next step the developed instrument was validated for content, internal and external validity. Finally the tool was finalized and tested for reproducibility and inter-rater agreement. RESULTS: The final validated version included six main categories for treatment-related problems (Indication, Effectiveness, Safety, Knowledge, Adherence and Miscellaneous). These categories include a total of nine subcategories and a total of 29 treatment related problems. CONCLUSION: The treatment-related problems assessment and classification tool introduced in this paper was applied to actual patient cases and proved to be valid. This tool also has several features that are new.

Adverse Drug Reaction Reporting Systems↗
PubMed2006

QSAR prediction of estrogen activity for a large set of diverse chemicals under the guidance of OECD principles.

A large number of environmental chemicals, known as endocrine-disrupting chemicals, are suspected of disrupting endocrine functions by mimicking or antagonizing natural hormones, and such chemicals may pose a serious threat to the health of humans and wildlife. They are thought to act through a variety of mechanisms, mainly estrogen-receptor-mediated mechanisms of toxicity. However, it is practically impossible to perform thorough toxicological tests on all potential xenoestrogens, and thus, the quantitative structure--activity relationship (QSAR) provides a promising method for the estimation of a compound's estrogenic activity. Here, QSAR models of the estrogen receptor binding affinity of a large data set of heterogeneous chemicals have been built using theoretical molecular descriptors, giving full consideration to the new OECD principles in regulation for QSAR acceptability, during model construction and assessment. An unambiguous multiple linear regression (MLR) algorithm was used to build the models, and model predictive ability was validated by both internal and external validation. The applicability domain was checked by the leverage approach to verify prediction reliability. The results obtained using several validation paths indicate that the proposed QSAR model is robust and satisfactory, and can provide a feasible and practical tool for the rapid screening of the estrogen activity of organic compounds.

Algorithms↗
PubMed2003

Prediction of aromatic amines mutagenicity from theoretical molecular descriptors.

In the present research the mutagenicity data (Ames tests TA98 and TA100) for various aromatic and heteroaromatic amines, a data set extensively studied by other quantitative structure-activity relationship (QSAR)-authors, have been modeled by a wide set of theoretical molecular descriptors using linear multivariate regression (MLR) and genetic algorithm-variable subset selection (GA-VSS). The models have been calculated on a subset of compounds selected by a D-optimal experimental design. Moreover, they have been validated by both internal and external validation procedures showing satisfactory predictive performance. The models proposed here can be useful in predicting data and setting a testing priority for those compounds for which experimental data are not available or are not yet synthesized.

Algorithms↗
PubMed1994

[Cultural and linguistic validation, in Spanish, of the International Prostatic Symptoms Scale (I-PSS)].

Formal presentation of the cultural and linguistic validation, in Spanish, of the International Prostatic Symptoms Scale (I-PSS). The process for the official translation into Spanish of the questionnaire on prostatic symptomatology and quality of live derived from urinary symptoms, has followed a methodology common to several countries (UK, Italy, Norway, The Netherlands and Spain) which consisted in: translation into Spanish of the original American-English version published by the WHO in 1992, by two independent bilingual urologists; re-translation into English, checking any conceptual and semantic changes that had caused difficulties in the process of translation/re-translation; final choice of the text by an International Committee based both on the data provided by the above process and the experience of the Central Committee accrued over their relationships with the various National Committees. The resulting text was applied to 33 patients with prostate disease and 12 controls, individually recording any difficulty of interpretation and choice of answer observed for each of the questions. The final text herewith presented constitutes the official reference for the Spanish translation of the International Prostatic Symptoms Scale (I-PSS) which should be used for future symptomatic evaluations. The purpose of this cultural and linguistic validation is to secure that the application of these scales provides comparable and consistent numerical results in those countries where the translation has not been officially validated.

Cultural Characteristics↗