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PubMed2005

Assessment of subjective health and health-related quality of life in persons with acquired or degenerative brain injury.

PURPOSE OF REVIEW: Health-related quality of life is a new outcome variable in neurology. Several generic measures aim at assessing this variable in adults with neurological diseases. Disease-specific measures are still rare; however, individuals with neurological diseases frequently suffer from cognitive impairment, yet are often excluded from health-related quality of life investigations. When included in such studies, cognitive functioning is not monitored via neuropsychological evaluation, possibly leading to methodological problems. Papers from May 2004 until July 2005 are reviewed with respect to psychometric quality and information about persons after traumatic brain injury, stroke, Parkinson's disease or dementia. RECENT FINDINGS: Several new cross-sectional and longitudinal outcome studies are reviewed. The Medical Outcome Study Short Form with 36 items, the Sickness Impact Profile and the Nottingham Health Profile were identified as the most frequently used measures in neurology. For traumatic brain injury, two new generic instrument validations (Life Satisfaction Index-A, Subjective Quality of Life Profile) and one internationally validated disease-specific development (Quality of Life after Brain Injury) were found; for stroke, one disease-specific tool (Burden of Stroke Scale) was identified. In Parkinson's disease, the disease-specific health-related quality of life measure Parkinson's Disease Questionnaire-39 is well validated. In dementia, three dementia-specific instruments (Quality of Life for Dementia, Quality of Life in Late-Stage Dementia Scale and Quality of Life in Alzheimer's Disease Scale) seem to be valid. SUMMARY: In neurology, only a few measures have been developed and validated for respondents with cognitive impairment, often showing poorer validity results than studies involving healthy persons. Health-related quality of life assessment should therefore be validated in the specific diseases and, if necessary, combined with a neuropsychological evaluation and a disease-specific health-related quality of life measure.

Animals↗

PubMed1993

Construct validation and the Rasch model: functional ability of healthy elderly people.

The purpose of this study was to test the construct validity of a measure of functional ability, developed with the intention of achieving a high degree of variability and capacity for discriminating among a group of healthy elderly people. Data were collected from 734 70-year-old people in Denmark in the county of Copenhagen. Functional ability was measured with the traditional activities of daily living and with a classification system developed specially for healthy elderly people. Construct validity was tested by the Rasch model for item analysis, addressing specifically the internal validity by assessing the homogeneity of items under different conditions. The results show that the proposed measure of functional ability is a combination of six different dimensions, divided into 3 types: mobility function, lower limb function and upper limb function. With regard to these three types decreased functional ability can appear by either tiredness or reduced speed.

Activities of Daily Living↗

PubMed2000

[Clinical trials in bronchial asthma].

Most of the clinical trials with new drugs on the treatment of asthma are carried out in well selected patients who are not representative of a very clinically heterogeneous disease, with periodic controls differing from those normally undertake in the general practice and specialist consultations. The clinical trials are usually performed over very short periods of time while the normal pharmacologic treatment of asthma requires prolonged treatment. The external validity of these studies is unknown but it is probably not comparable to internal validity. To improve the quality of the clinical trials on asthma, studies should be carried out on patients representing the global population in conditions which are closer to those of the real world and during prolonged periods of time.

Asthma↗

PubMedDate not supplied

Questionnaire for measuring oral health-related quality of life in eight- to ten-year-old children.

PURPOSE: This study measured oral health-related quality of life for children, which involved the construction of child perceptions questionnaires (CPQs) for ages 6 to 7, 8 to 10, and 11 to 14. The purpose of this study was to present the development and evaluation of the CPQ for 8- to 10-year-olds (CPQ8-10). METHODS: Questions (N=25) were selected from the CPQ for 11- to 14-year-olds based on the child development literature and input from parents, child psychologist, and teacher of grades 3 and 4. Validity and reliability were evaluated on 68 and 33 children, respectively. RESULTS: There was a positive moderate correlation between the CPQ8-10 score and overall well-being rating (R=.45). The level of impact was slightly higher in the orofacial than in the pediatric dentistry group (mean score=19.1 vs 18.4, respectively). Hypotheses concerning the relationship between the CPQ8-10 score and number of decayed surfaces were confirmed with R=.29, and the mean score higher in caries-afflicted than caries-free children (21.1 vs 14.7). The Cronbach's alpha and intraclass correlation coefficients were 0.89 and 0.75, respectively. CONCLUSIONS: Results suggest good construct validity, internal consistency, reliability and test-retest reliability, but do not demonstrate discriminative validity. This is consistent, however, with theoretical models of oral disease and its consequences. Further research is required, as these are preliminary findings based on convenience sampling.

Attitude to Health↗

PubMed1990

Selective internal radiation therapy: validation of intraoperative dosimetry.

In selective internal radiation (SIR) therapy of hepatic metastases, tumor vasculature is preferentially embolized with high-energy beta-emitting yttrium-90-labeled microspheres. To enable accurate estimation of the resultant absorbed radiation doses to tissues, an intraoperative beta detection probe is used to scan the liver surface. The validity of the response of this probe to Y-90 and its clinical application were assessed with a phantom containing varying activities and with biopsy samples obtained from patients being treated with SIR therapy. A linear relationship was found between the probe counts taken from the biopsy samples and the calculated tissue radiation doses from the specific activities of each sample. This relationship was repeated with probe counts determined against a water phantom containing various activities of Y-90. The probe was shown to respond minimally to bremsstrahlung. The use of the probe in measuring tissue radiation doses at laparotomy provides the opportunity to control dose administration during SIR therapy. In this way, subtherapeutic exposure of normal tissue can be assured while tumor tissue receives maximal radiation levels.

Brachytherapy↗

PubMed2005

Validity and reliability of the Italian version of the Quality-of-Life in Epilepsy Inventory (QOLIE-31).

PURPOSE: To develop an Italian adaptation of the shortened version of the Quality-of-Life in Epilepsy Inventory (QOLIE-31). METHODS: The study population comprised 503 consecutive ambulatory patients with epilepsy from 44 centers. Internal validity was tested by factor analysis, to detect similarities to and differences from the original version, and by multitrait/multi-item analysis, to assess item convergent and discriminant validity. External validity testing included correlation to the SF-36 Inventory, to check the properties of the epilepsy-specific dimensions. Validity testing was completed by analysis of variance (ANOVA) of QOLIE-31 dimension scores against demographic and clinical variables, including age, sex, seizure frequency and number of drugs. RESULTS: The domains showing the highest internal consistency and the best discriminant validity were Medication effect, and Seizure worry. Social functioning had the lower discriminant validity. With reference to the SF-36 scores, the study patients were slightly but constantly below the population values, mostly for General health and Role physical domains. All QOLIE-31 dimensions were sensitive to almost any demographic and clinical variable, except for Medication effects (sensitive to number of drugs) and Energy-fatigue (sensitive to age). CONCLUSIONS: Except for Social functioning, the psychometric properties of the Italian adaptation of the QOLIE-31 Inventory are fairly good and similar to the American version and the Spanish translation. Social functioning scale suffers shortcomings because of life constraints caused by epilepsy (with missing values for regular job and driving license).

Adolescent↗

PubMed2003

The OECD program to validate the rat uterotrophic bioassay: an overview.

The Organisation for Economic Co-operation and Development has undertaken an international validation program for the rodent uterotrophic bioassay. This validation program comprised two major parts. The first part was the development of a detailed background review document compiling the existing data on the bioassay's history, the molecular and physiologic basis for the bioassay's mechanistic relevance to detect estrogen agonists and antagonists, a review of important bioassay protocol parameters, and a review of the data generated by in vitro assays, previous uterotrophic bioassays, and developmental and reproductive assays to assess and support the overall predictivity of the uterotrophic bioassay. The second part was an extensive multiyear effort managed by a validation management group to demonstrate the operating characteristics of four protocols. The effort was conducted in two phases. The phase 1 results with the reference agonist ethinyl estradiol (EE) and antagonist ZM 189,154 has been published previously. This Environmental Health Perspectives mini-monograph is devoted to the phase 2 work using five weak estrogen agonists, bisphenol A, genistein, methoxychlor, nonylphenol, and o,p -DDT, as well as the negative substance dibutylphthalate. These data show that all protocols successfully detected increases in uterine weights when a sufficient dose level of the weak agonists was administered, whether the substances were known or provided as coded doses to the laboratory. The data with both the reference EE and all five weak agonists are reproducible over time and under a variety of different experimental conditions (e.g., animal strain, diet, housing, bedding, vehicle, animal age). In conclusion, all protocols now have sufficient data to support their validity.

Age Factors↗

PubMed1999

Revised susceptibility, benefits, and barriers scale for mammography screening.

The purpose of this research was to revise scales measuring perceived susceptibility to breast cancer and perceived benefits and barriers to mammography utilization. A total of 618 women age 50 and over who were enrolled in a large intervention study participated in data collection. Scales were revised beginning with focus group input. Analyses included internal consistency reliability, test-retest reliability, factor analysis, confirmatory analysis, and known groups techniques to test construct validity. Internal consistency ranged from .75 to .88, and test reliabilities from .59 to .72. Construct validity was confirmed with exploratory and confirmatory factor analyses, as well as known group techniques. Overall these scales represent an improvement in those previously reported.

Breast Neoplasms↗

PubMed1995

Validity of the recording of ischaemic heart disease and chronic obstructive pulmonary disease in the Saskatchewan health care datafiles.

The internal validity of the recording of information about ischaemic heart disease (IHD) and chronic obstructive pulmonary disease (COPD) in the administrative health care datafiles of the Canadian province of Saskatchewan is investigated. Comparisons between hospital data and medical charts for acute myocardial infarction and chronic airways obstruction patients showed excellent diagnostic agreement: 97 per cent and 94 per cent, respectively. Appropriate physician service claims were identified for 89 per cent of hospitalizations for IHD and COPD and exact concordance between diagnoses in the two datafiles varied between 15 per cent for acute/sub-acute IHD and 80 per cent for asthma; including any physician diagnosis within the same broad category (IHD or COPD) increased concordance to 79-94 per cent for IHD and 64-88 per cent for COPD. Contextual information related to the hospitalizations was clinically and epidemiologically realistic.

Adolescent↗

PubMed2002

Is EQ-5D a valid measure of HRQoL in patients with movement disorders? A comparison with SF-36 and FIM questionnaires.

We assessed the descriptive part of the EQ-5D system in rehabilitation patients with validity severe moving disorders and compared it with the FIM and the SF-36 Health Survey in a sample of 60 patients. We analyzed the EQ-5D convergent validity and the correlations between EQ-5D scores and a clinical variables. The internal validity of the EQ-5D instrument proved good. Moreover, the EQ-5D discriminated symptom severity as scored by the FIM and the SF-36 correspondent subscales. We analyzed the sensitivity of the EQ-5D only with respect to the ability of patients to move with or without a wheelchair. Most patients considered "moving a wheelchair" as a good way of "getting about." This investigation can be considered a pilot study on the performance of the EQ-5D in a group of pathologies involving various degrees of movement disorders. The findings show possible problems of misinterpretation in the levels of the mobility dimension.

Journal Article↗

PubMed2000

Are clinical practice guidelines valid for primary care?

Development of evidence-based clinical practice guidelines has emphasized treatment efficacy under methodologically rigorous conditions; internal validity (i.e., efficacy) has been assessed well. Despite their experimental foundations, guidelines originally were considered physician education tools relevant to singular, idealized encounters. Now, in rushing to generalize, quantify, and regulate quality, guidelines are being applied to whole populations as quality review criteria. Clinical guidelines do not make operational how, or even make clear whether they should be so used. We studied the external validity, the generalizability and measurability for primary care, of a guideline for treatment of systolic heart failure. Patient and clinical factors reducing generalizability were examined. Imprecise definition and reliance on single measures of recommendations were studied as limits to measurability. Patient, physician, organizational, and system factors influenced guideline validity. Attention to myriad invalidity sources undermining implementation and evaluation of efforts to improve quality and outcomes of primary care is critical.

Heart Failure↗

PubMed2001

Scoring systems and risk assessment for upper gastrointestinal bleeding.

Mortality associated with acute upper gastrointestinal bleeding remains high despite advances in diagnosis and therapy. This was emphasized by the findings of the seminal English National Audit of acute gastrointestinal haemorrhage undertaken by Rockall and associates in the mid-1990s. The apparent lack of progress is largely due to less selective reporting in an ageing population with greater co-morbidity. Thus some deaths will be unavoidable even with exemplary treatment. Managing high risk patients in a dedicated area with close cooperation between medical and surgical gastroenterologists has been shown to improve outcome. The challenge is to select those patients who have most to gain from such a scarce and expensive resource so that their treatment can be optimized. Various risk factors have been identified to help achieve this end. Rockall's national audit data suggest that avoidable deaths remain a problem in most district general hospitals. A simple numerical score was derived from these audit data (Rockall score) to predict rebleeding and mortality. The score is based on five variables: age, shock, co-morbidity, endoscopic diagnosis and stigmata of recent haemorrhage. It has the advantage that pre-endoscopic assessment can be made by inexperienced medical or nursing staff. The system was validated internally in a second audit by Rockall and co-workers, and subsequent external validation has come from New Zealand and the Netherlands. The score is less reliable at predicting rebleeding than death and so is, as yet, an imperfect instrument. The scoring system has also proven valuable in selecting low risk patients for early discharge (resulting in health care economies) and for comparing outcome data from different hospitals or populations. Endoscopic treatment has recently been shown to reduce rebleeding rates and perhaps mortality. These advances in therapy are becoming more widely adopted and may influence the predictive ability of the Rockall score. The study from Edinburgh, in this issue, although small and with wide confidence intervals, supports the ability of the Rockall score to identify high risk cases amongst those given endoscopic treatment. It also suggests that an adjustment of the score may be required in these circumstances to prevent overcalling the risk of rebleeding and death.

Endoscopy, Gastrointestinal↗

PubMed1999

International standards for growth hormone.

Since 1955, with the establishment by the World Health Organization of the first International Standard (IS) for bovine growth hormone (GH) for bioassay, there have been a number of developments in the standardization of GH. Two GH ISs are in current use: the IS for human GH established in 1982 and the IS for somatropin (recombinant DNA-derived GH) established in 1994. The availability of two such standards does not encourage reproducibility of GH estimates between different laboratories. The author proposes that the international validation and adoption of the IS for somatropin, which has the advantage of an internationally agreed specific activity of 3 IU/mg, as the primary reference standard for all GH immunoassays would finally eliminate this source of variation in GH estimates.

Animals↗

PubMed2026

Artificial Intelligence-Driven Multi-Omics Analysis Reveals Hydroxytyrosol Targeting of the TXNIP-NLRP3 Inflammasome Axis in Traumatic Brain Injury.

Traumatic brain injury (TBI) induces secondary neuroinflammation driven by oxidative stress, inflammasome activation, and immune remodeling, yet specific mechanism-guided pharmacological interventions remain limited. This study established an artificial intelligence (AI)-integrated network pharmacology and multi-omics framework to evaluate whether hydroxytyrosol (HT), an olive-derived natural polyphenol, may regulate TBI-related neuroinflammatory targets centered on the TXNIP/NLRP3 inflammasome axis. Starting from the SMILES structure of HT, potential targets were predicted using PharmMapper, SwissTargetPrediction, and the Similarity Ensemble Approach and were standardized to UniProt identifiers. TBI-associated genes were integrated from GeneCards, DisGeNET, OMIM, and the Therapeutic Target Database. The overlapping target set was analyzed using STRING-based protein-protein interaction (PPI) networks, MCODE, CytoHubba, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. Public GEO transcriptomic datasets (GSE123831 and GSE104687) were used for cross-platform expression validation, differential expression analysis, and exploratory CIBERSORT-based immune infiltration estimation. Random forest (RF), multilayer perceptron (MLP), graph convolutional network (GCN), graph attention network (GAT), SHAP/LIME explainability analysis, LASSO inflammatory-risk scoring, and two-sample Mendelian randomization (MR) were further applied for target prioritization, immune phenotype mapping, and genetic association analysis. Seventy-three overlapping HT-TBI targets were identified. PPI and topology analyses prioritized TXNIP, NLRP3, CASP1, MAPK1, and TP53 as key hubs enriched in inflammasome activation, oxidative stress, apoptosis, and NOD-like receptor signaling. TXNIP, NLRP3, and CASP1 were consistently upregulated in both TBI transcriptomic datasets. LM22-based immune deconvolution suggested increased pro-inflammatory immune signatures and a positive TXNIP-M1 macrophage association (r = 0.63, p < 0.001), which should be interpreted as a transcriptome-derived hypothesis rather than validated murine immune-cell proportions. AI-based models consistently ranked TXNIP/NLRP3 as high-contribution features under internal validation, and removal of these targets reduced model performance. A five-gene inflammatory score achieved an internally evaluated AUC of 0.87, while two-sample MR supported positive genetic associations involving TXNIP expression, TBI risk, NLRP3 and IL-1β expression. Collectively, these findings prioritize the TXNIP/NLRP3/CASP1 module as a computationally supported candidate mechanism through which HT may influence oxidative stress-inflammasome-immune coupling in TBI. This study provides an interpretable drug-target-pathway-phenotype framework and identifies TXNIP, NLRP3, and CASP1 as priority nodes for future experimental validation.

Artificial Intelligence↗

PubMed2005

The WHO-DAS II: psychometric properties in the measurement of functional health status in adults with acquired hearing loss.

The World Health Organization's (WHO) Disability Assessment Scale II (WHO-DAS II) is a generic health-status instrument firmly grounded in the WHO's International Classification of Functioning, Disability and Health (WHO-ICF). As such, it assesses functioning for six domains: communication, mobility, self-care, interpersonal, life activities, and participation. Domain scores aggregate to a total score. Because the WHO-DAS II contains questions relevant to hearing and communication, it has good face validity for use as an outcome measure for audiologic intervention. The purpose of the present study was to determine the psychometric properties of the WHO-DAS II on a sample of individuals with adult-onset hearing loss, including convergent validity, internal consistency, and test-retest stability. Convergent validity was established by examining correlations between the WHO-DAS II (domain and total scores) and the Abbreviated Profile of Hearing Aid Benefit (APHAB) and the Hearing Aid Handicap for the Elderly (HHIE), two disease-specific measures, as well as with the Short Form-36 for veterans (SF-36V), a second generic measure. Data on all four measures were collected from 380 older individuals with adult-onset hearing loss who were not hearing aid users. The results of the convergent validity analysis revealed that the WHODAS II communication domain score was moderately and significantly correlated with scores on the APHAB and the HHIE. WHO-DAS II interpersonal and participation domain scores and the total scores were also moderately and significantly correlated with HHIE scores. These findings support the validity of using the WHO-DAS II for assessing activity limitations and participation restrictions of adult-onset hearing loss. Several WHO-DAS II domain scores and the total score were also significantly and moderately-markedly correlated with scores from the SF-36V. These findings support the validity of the WHO-DAS II as a generic health-status instrument. Internal consistency reliability for all the domain scores was adequate for all but the interpersonal domain. Test-retest stability for all the domain scores was adequate. Critical difference values were calculated for use in clinical application of the WHO-DAS II. From these findings, we concluded that the WHO-DAS II communication, participation, and total scores can be used to examine the effects of adult-onset hearing loss on functional health status. Further work examining the utility of the WHO-DAS II as an outcome measure for hearing aid intervention is warranted.

Activities of Daily Living↗

PubMed2003

Predicting outcome in ischemic stroke: external validation of predictive risk models.

BACKGROUND: Six multivariable models predicting 3-month outcome of acute ischemic stroke have been developed and internally validated previously. The purpose of this study was to externally validate the previous models in an independent data set. SUMMARY OF REPORT: We predicted outcomes for 299 patients with ischemic stroke who received placebo in the National Institute of Neurological Disorders and Stroke rt-PA trial. The model equations used 6 acute clinical variables and head CT infarct volume at 1 week as independent variables and 3-month National Institutes of Health Stroke Scale, Barthel Index, and Glasgow Outcome Scale as dependent variables. Previously developed model equations were used to forecast excellent and devastating outcome for subjects in the placebo tissue plasminogen activator data set. Area under the receiver operator characteristic curve was used to measure discrimination, and calibration charts were used to measure calibration. The validation data set patients were more severely ill (National Institutes of Health Stroke Scale and infarct volume) than the model development subjects. Area under the receiver operator characteristic curves demonstrated remarkably little degradation in the validation data set and ranged from 0.75 to 0.89. Calibration curves showed fair to good calibration. CONCLUSIONS: Our models have demonstrated excellent discrimination and acceptable calibration in an external data set. Development and validation of improved models using variables that are all available acutely are necessary.

Aged↗

PubMed2005

Challenges in systematic reviews that assess treatment harms.

An evidence synthesis of a medical intervention should assess the balance of benefits and harms. Investigators performing systematic reviews of harms face challenges in finding data, rating the quality of harms reporting, and synthesizing and displaying data from different sources. Systematic reviews of harms often rely primarily on published clinical trials. Identifying important harms of treatment and quantifying the risk associated with them, however, often require a broader range of data sources, including unpublished trials, observational studies, and unpublished information on published trials submitted to the U.S. Food and Drug Administration. Each source of data has some potential for yielding important information. Criteria for judging the quality of harms assessment and reporting are still in their early stages of development. Investigators conducting systematic reviews of harms should consider empirically validating the criteria they use to judge the validity of studies reporting harms. Synthesizing harms data from different sources requires careful consideration of internal validity, applicability, and sources of heterogeneity. This article highlights examples of approaches to methodologic issues associated with performing systematic reviews of harms from 96 Evidence-based Practice Center evidence reports.

Evidence-Based Medicine↗

PubMed2001

Efficient regression calibration for logistic regression in main study/internal validation study designs with an imperfect reference instrument.

An extension to the version of the regression calibration estimator proposed by Rosner et al. for logistic and other generalized linear regression models is given for main study/internal validation study designs. This estimator combines the information about the parameter of interest contained in the internal validation study with Rosner et al.'s regression calibration estimate, using a generalized inverse-variance weighted average. It is shown that the validation study selection model can be ignored as long as this model is jointly independent of the outcome and the incompletely observed covariates, conditional, at most, upon the surrogates and other completely observed covariates. In an extensive simulation study designed to follow a complex, multivariate setting in nutritional epidemiology, it is shown that with validation study sizes of 340 or more, this estimator appears to be asymptotically optimal in the sense that it is nearly unbiased and nearly as efficient as a properly specified maximum likelihood estimator. A modification to the regression calibration variance estimator which replaces the standard uncorrected logistic regression coefficient variance with the sandwich estimator to account for the possible misspecification of the logistic regression fit to the surrogate covariates in the main study, was also studied in this same simulation experiment. In this study, the alternative variance formula yielded results virtually identical to the original formula. A version of the proposed estimator is also derived for the case where the reference instrument, available only in the validation study, is imperfect but unbiased at the individual level and contains error that is uncorrelated with other covariates and with error in the surrogate instrument. Replicate measures are obtained in a subset of study participants. In this case it is shown that the validation study selection model can be ignored when sampling into the validation study depends, at most, only upon perfectly measured covariates. Two data sets, a study of fever in relation to occupational exposure to antineoplastics among hospital pharmacists and a study of breast cancer incidence in relation to dietary intakes of alcohol and vitamin A, adjusted for total energy intake, from the Nurses' Health Study, were analysed using these new methods. In these data, because the validation studies contained less than 200 observations and the events of interest were relatively rare, as is typical, the potential improvements offered by this new estimator were not apparent.

Adult↗