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PubMed2001

The burden of musculoskeletal diseases in the general population of Spain: results from a national survey.

OBJECTIVE: The objective of the EPISER study was to estimate the prevalence of rheumatoid arthritis (RA), low back pain, hand and knee osteoarthritis (OA), and fibromyalgia in the adult Spanish population, and to assess the impact of these diseases on function and quality of life, and use of health and social resources. METHODS: 2998 subjects aged 20 years or above were randomly selected by stratified multistage cluster sampling from the censuses of 20 municipalities. Trained rheumatologists carried out structured visits at which subjects were asked about rheumatic symptoms and sociodemographic characteristics, completed validated instruments for measuring function (HAQ) and quality of life (SF-12), and underwent a standardised physical examination. Cases were defined by previously validated criteria. RESULTS: The estimated prevalences with 95% confidence intervals were as follows: RA lifetime cumulative: 0.5% (0.3 to 0.9); low back pain: 14.8% (12.2 to 17.4); symptomatic knee OA: 10.2% (8.5 to 11.9); hand OA: 6.2% (5.9 to 6.5); fibromyalgia: 2.4% (1.5 to 3.2). Most conditions significantly impaired function and quality of life. CONCLUSIONS: The EPISER study has internal and external validity for application of the results to the adult Spanish population. The diseases studied affect a significant proportion of the population, with various degrees of impact on disability and quality of life resulting in a significant number of physician visits, work disability, and medication use.

Adult↗
PubMed2000

Scoring the short form ICSmaleSF questionnaire. International Continence Society.

PURPOSE: The International Continence Society (ICS) ICSmale questionnaire was devised to provide a thorough evaluation of the occurrence and bothersomeness of lower urinary tract symptoms and their impact on the lives of men with benign prostatic disease. This report completes the developmental work on the questionnaire, producing the concise short form instrument, ICSmaleSF, with a valid, reliable and scientifically justified scoring system. MATERIALS AND METHODS: Two data sets were used. The short form version of the questionnaire was devised and initially evaluated using data on men with uncomplicated lower urinary tract symptoms who were involved in the CLasP randomized controlled trial comparing laser therapy with transurethral prostatic resection and conservative management or monitoring without active intervention. External validation of the scoring system was undertaken using data from phase II of the ICS benign prostatic hyperplasia (BPH) study, an observational study of outcome in men with lower urinary tract symptoms related to benign prostatic enlargement. All patients completed the developmental version of the ICSmale questionnaire. Parallel analysis on the CLasP data set identified items that were responsive to change or highly problematic, allowing other redundant and overlapping items to be eliminated. Factor analysis and Cronbach's alpha coefficients were used to examine the clustering of items. Regression models were used to investigate the validity of followup scores within and across treatment groups in the CLasP and ICS/BPH studies. RESULTS: The questionnaire, which originally comprised 22 items, was shortened to 11 items in the 2 distinct factors of voiding (ICSmaleVS) and incontinence (ICSmaleIS) symptoms. Cronbach's alpha coefficients were high at 0.76 for ICSmaleVS and 0.78 for ICSmaleIS. A simple additive score was calculated by adding the 5 items in ICSmaleVS and 6 in ICSmaleIS. ICSmaleVS and ICSmaleIS detected expected improvement in the laser therapy and transurethral prostatic resection groups, and stability in the conservative management group within CLasP. Similarly each subscore but particularly ICSmaleVS was sensitive to differences in the outcome of the range of treatments in the ICS/BPH study. While frequency and nocturia were highly problematic and sensitive to change individually, they did not load into the other main factors or correlate with each other. It is suggested that these symptoms should be evaluated separately with the additional inclusion of a single item measure of the impact of lower urinary tract symptoms on daily life. CONCLUSIONS: The ICSmaleSF represents a comprehensive, concise, valid and reliable instrument for evaluating men with lower urinary tract symptoms. Unlike other questionnaires in the field it contains subscores for the domains of voiding and incontinent symptoms as well as the separate consideration of frequency, nocturia and impact on daily life. We hope that it will become the tool of choice for the comprehensive evaluation of treatment of men with lower urinary tract symptoms associated with benign prostatic disease.

Humans↗
PubMed2004

The challenges of validating diagnostic methods relative to a conventional two-year caries clinical trial.

This paper is directed to the question, "What are the appropriate validation criteria for the use of a new clinical trial methodology as a replacement for a conventional two- to three-year caries study?" It is important to recognize that the objective of a two- to three-year randomized, controlled caries trial is to test a precisely framed hypothesis, regarding an experimental product's efficacy relative to a control product. The external validity of conventional two- to three-year caries clinical studies in determining the efficacy and safety of anti-caries products is well-accepted. However, caries clinical trials are not without limitations and have increasingly been viewed as inefficient with respect to measuring the disease process in a holistic manner. The endpoint of a caries lesion with loss of enamel integrity (cavitation) focuses on one end of the caries progression continuum at the expense of early caries initiation and progression. Several early caries detection methods have been developed that correlate with mineral loss of the tooth surface. These diagnostics differ from conventional visual-tactile and radiographic methods in that they are capable of detecting early non-cavitated lesions, and this can generate continuous data. As diagnostic methods become accepted, they will lead to study designs that diverge from the conventional two- to three-year caries studies. Modification of the existing two- to three-year conventional caries design for assessment of product effectiveness, whether by the introduction of a new diagnostic method or by modification of the overall clinical design, must result in a clinical design that is able to differentiate known treatments on the basis of caries prevention efficacy. Given that the fluoride dose response has been characterized in the literature, this should form the basis of any validation package for new methodologies. In conclusion, a minimum expectation for acceptance as a replacement to conventional testing should be that the method or design can differentiate products of known efficacy from one another and that the efficacy relationship observed in a two- to three-year conventional study can be observed with the new method or design.

Cariostatic Agents↗
PubMed2006

In vitro - in vivo correlation: from theory to applications.

A key goal in pharmaceutical development of dosage forms is a good understanding of the in vitro and in vivo performance of the dosage forms. One of the challenges of biopharmaceutics research is correlating in vitro drug release information of various drug formulations to the in vivo drug profiles (IVIVC). Thus the need for a tool to reliably correlate in vitro and in vivo drug release data has exceedingly increased. Such a tool shortens the drug development period, economizes the resources and leads to improved product quality. Increased activity in developing IVIVCs indicates the value of IVIVCs to the pharmaceutical industry. IVIVC can be used in the development of new pharmaceuticals to reduce the number of human studies during the formulation development as the main objective of an IVIVC is to serve as a surrogate for in vivo bioavailability and to support biowaivers. It supports and/or validates the use of dissolution methods and specification settings. This is because the IVIVC includes in vivo relevance to in vitro dissolution specifications. It can also assist in quality control for certain scale-up and post-approval changes (SUPAC). With the proliferation of modified-release products, it becomes necessary to examine the concept of IVIVC in greater depth. Investigations of IVIVC are increasingly becoming an integral part of extended release drug development. There must be some in vitro means of assuring that each batch of the same product will perform identically in vivo. This review article represents the FDA guidance, development, evaluation, and validation of an IVIVC to grant biowaivers, and to set dissolution specifications for oral dosage forms, biopharmaceutics classification systems (BCS), BCS biowaivers, application of BCS in IVIVC development and concept of mapping. The importance of dissolution media and methodology and pharmacokinetic studies in the context of IVIVC has been highlighted. The review also covers the literature examples of IVIVCs regarding internal and external validation, compendial dissolution assessment, formulation dependency of IVIVCs, and IVIVCs of pure enantiomers versus racemate drugs. The same principles of IVIVC used for oral extended release products may be applied for non-oral products such as parenteral depot formulations and novel drug delivery systems as well.

Biological Availability↗
PubMed2005

Psychometric properties and validation of the German-language King's Health Questionnaire in women with stress urinary incontinence.

AIMS: The purpose of this study was to evaluate the psychometric properties of and validate the German-language version of the King's Health Questionnaire (KHQ) in women with stress urinary incontinence (SUI). METHODS: A total of 145 women treated for stress incontinence with surgery or physiotherapy completed the the KHQ and the SF-36 before and after treatment. Psychometric analyses of the quality of life (QoL) instruments determined the reliability (Cronbach's alpha), internal and external validity, and responsiveness of the KHQ subscales. RESULTS: The KHQ showed good internal consistency, content validity, and criterion validity as measured by correlation with scores on the SF-36. Cronbach's alpha coefficient ranged from 0.76 to 0.86, indicating a high internal consistency of the subscales. Concerning criterion validity, correlations between the KHQ subscales and the SF-36 were low to moderate. The highest correlation was found between the general health perception subscales of both questionnaires. CONCLUSIONS: The results indicate good psychometric properties for the German-language KHQ.

Adult↗
PubMed1986

Alcoholic subtypes based on multiple assessment domains. Validation against treatment outcome.

Research in the area of subtype development within alcoholic populations has undergone a number of changes over the recent years. First, there has been a shift from subtype derivation based on a priori comparative approaches toward a more recent use of a posteriori correlational approaches such as cluster analysis. Second, there has been an increased multivariate focus in which multiple measures from a number of practically and/or theoretically relevant assessment domains are entered into the classificatory process. Third, there has been an increased emphasis on the external validation of derived clusters. The present chapter briefly reviews these issues, using examples of research from the Seattle Veterans Administration Medical Center to illustrate each of these shifts across a series of studies focusing on the development of alcoholic subtypes. Finally, the results of a recent subtype identification and validation study will be presented to illustrate the difficulties in and advantages of a multidomain cluster analytic strategy.

Adult↗
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↗
PubMed2004

A dependency model for patients with Alzheimer's disease: its validation and relationship to the costs of care--the LASER-AD Study.

BACKGROUND: Loss of independence becomes more marked as Alzheimer's disease (AD) progresses and contributes significantly to its societal and economic burden. Existing measures of functional disability focus either on basic or on instrumental activities of daily living (ADL). It would be more appropriate to combine these but, using existing assessment tools, this would involve considerable quantitative analysis. Recently, a qualitative and pragmatic system of classifying AD patients according to levels of dependency has been developed in a Belgian cohort. OBJECTIVES: To validate independently, in a UK community setting, a functional classification model of AD patients and to explore the relationship between dependency and costs of care using this model. RESEARCH DESIGN AND METHODS: Longitudinal epidemiological study of 224 AD patients. Data were collected at baseline and at 6 months on ADL, global state, cognition, behavioural dimensions, depression, quality of life and resource utilisation using validated instruments. An automatic classification algorithm was performed to allow identification of dependency clusters. The scheme was tested for validity against other simultaneously collected data including health and social care costs. The relationship between dependency and costs of care was explored using ANOVA models. RESULTS: Analysis of the ADL assessment instruments produced three ADL sub-scores by which patients could be classified into one of three disability clusters: ('non-dependent', 'non-dependent with instrumental functional disability', and 'dependent'). Good external validity of the classification scheme was demonstrated by correlation with simultaneously collected data. After a backward selection process on ANOVA model (at a 5% level), institutionalisation and the most dependent status were the most significant cost drivers. CONCLUSIONS: Qualitative classification of AD patients using dependency levels is a simple and validated approach. Applying this approach showed that institutionalisation and the most 'dependent' status were independently and significantly associated with high care cost.

Activities of Daily Living↗
PubMed1987

Assessment of assertion.

Behavioral assessment of assertion is an evolving technology. Although there have been many recent advances in the assessment of assertion, many unresolved issues continue to plague researcher and clinician alike. At a conceptual level, a precise theoretical rationale of assertion has yet to be articulated and accepted. Comprehensive identification of the various parameters that influence assertive responding have not been adequately evaluated, although person and situational variables are widely accepted parameters. Although a plethora of assessment instruments and strategies have emerged, more attention needs to be diverted to establishing their psychometric properties. There have been some promising starts, though there continues to be relatively little psychometric support for the adequacy of existing measures. Several self-report instruments have reasonably well-documented reliability and validity, but questions remain regarding the accuracy of self-reported assertion. In addition, a flood of new instruments continues the proliferation of measures. Researchers would be better advised to direct their efforts to establishing psychometric support for the more promising of the existing instruments than in continuing to expand energy on unproven new measures. Serious reservations have emerged regarding, in particular, the external validity of role-play assessment and cloud the confidence that can be placed on findings generated from role-play measures. The issues that have been critically identified throughout this chapter are not new. They occur time and time again in the assessment literature of the past decade. Yet the field continues to reflect inattention to cautions that have been repeatedly voiced. Measures continue to flood the literature without adequate psychometric support, and researchers rush toward outcome evaluation without attending to the questionable utility of findings generated from unproven measures. There has been a great deal of progress in a relatively short period of time. However, clearer answers are necessary before scientific credibility can be established for social skills research in general--and assertion research in particular.

Arousal↗
PubMed2002

Predicting outcome after acute and subacute stroke: development and validation of new prognostic models.

BACKGROUND AND PURPOSE: Statistical models to predict the outcome of patients with acute and subacute stroke could have several uses, but no adequate models exist. We therefore developed and validated new models. METHODS: Regression models to predict survival to 30 days after stroke and survival in a nondisabled state at 6 months were produced with the use of established guidelines on 530 patients from a stroke incidence study. Three models were produced for each outcome with progressively more detailed sets of predictor variables collected within 30 days of stroke onset. The models were externally validated and compared on 2 independent cohorts of stroke patients (538 and 1330 patients) by calculating the area under receiver operating characteristic curves (AUC) and by plotting calibration graphs. RESULTS: Models that included only 6 simple variables (age, living alone, independence in activities of daily living before the stroke, the verbal component of the Glasgow Coma Scale, arm power, ability to walk) generally performed as well as more complex models in both validation cohorts (AUC 0.84 to 0.88). They had good calibration but were overoptimistic in patients with the highest predicted probabilities of being independent. There were no differences in AUCs between patients seen within 48 hours of stroke onset and those seen later; between ischemic and hemorrhagic strokes; and between those with and without a previous stroke. CONCLUSIONS: The simple models performed well enough to be used for epidemiological purposes such as stratification in trials or correction for case mix. However, clinicians should be cautious about using these models, especially in hyperacute stroke, to influence individual patient management until they have been further evaluated. Further research is required to test whether additional information from brain imaging improves predictive accuracy.

Acute Disease↗
PubMed2003

Predicting mortality in patients with cirrhosis of liver with application of neural network technology.

BACKGROUND: Prediction of mortality from cirrhosis is important in planning optimal timing of liver transplantation and other interventions. We evaluated the role of the Artificial Neural Network (ANN), which uses non-linear statistics for pattern recognition in predicting one-year liver disease-related mortality using information available during initial clinical evaluation. METHODS: The ANN was constructed using software with data from a training set (n = 46) selected at random from a cohort of adult cirrhotics (n = 92). After training, validation was performed in the remaining patients (n = 46) whose outcome in terms of one-year mortality was unknown to the network. The performance of ANN was compared to those of a logistic regression model (LRM) and Child-Pugh's score (CPS). Death (related to cirrhosis/its complications) within one year of inclusion was the outcome variable. The ANN was also tested in an external validation sample (EVS, n = 62) from another hospital. RESULTS: Patients in the EVS were younger (mean age, 41 vs 45 years), infrequently of alcoholic etiology (5% vs 49%), had less severe disease (mean CPS 6.6 vs 10.8), and had lower one-year mortality (13 vs 46%). In the internal validation sample, ANN's accuracy was 91%, sensitivity 90% and specificity 92% in prediction of one-year mortality; area under the receiver-operating characteristic (ROC) curve was 0.94. The performance of the LRM (accuracy 74%) and the CPS (accuracy 55%) was significantly worse than ANN (P < 0.05, McNemar's test). Despite differences in the characteristics of the two groups, the ANN performed fairly well in the EVS (accuracy of 90%, area under curve 0.85). CONCLUSIONS: ANN can accurately predict one-year mortality in cirrhosis and is superior to CPS and LRM.

Adult↗
PubMed2005

The experience of carers of patients with severe mental illness: a comparison between London and Bologna.

PURPOSE: The experience of care giving inventory (ECI) is a self-reported measure of the caregiving experience as seen by the carer of a person with a serious mental illness. It comprises eight negative subscales and two positive subscales; positive and negative scores are obtained from these (ECI total positive and ECI total negative). This study aims to assess the validity and the reliability of the Italian version of the ECI and to compare the experience of carers in London and Bologna as measured by the ECI. METHOD: The sample consisted of 95 Bologna carers and 69 London carers of patients suffering from a functional psychotic disorder. The internal consistency of the Italian ECI and correlation between the Italian ECI total negative and the GHQ-12 (external validity) were estimated. Independent t-tests and chi-squared tests were used to compare sample characteristics and mean ECI scores. Regression analyses were used to control for confounders. RESULTS: Internal consistency and validity of the Italian ECI were similar to these previously found. The Bologna caregivers had a higher ECI total negative than London carers; this difference was partially explained by worse patients' functioning and by a higher proportion of parents in Bologna. Bologna carers scored significantly lower on ECI total positive after controlling for relationship and patient functioning. CONCLUSIONS: The Italian ECI is a well-accepted and valid instrument to describe caregiving experiences. The similar scores in ECI total negative between London and Bologna underline a cross-cultural consistency of negative experience of caregiving and re-emphasise the importance of patients functioning in different cultural contexts. The differences found for ECI total positive suggest area for further research.

Attitude to Health↗
PubMed2026

Deep learning-based multimodal pathogenomics integration for precision cancer prognosis.

BACKGROUND: Recent studies have revealed valuable prognostic insights in haematoxylin and eosin (H&E)-stained histological sections and transcriptomic profiles, suggesting potential applications in machine learning. However, existing methods lack sufficient intra- and inter-modal interactions, and face challenges in clinical validation due to incomplete multimodal data. METHODS: We proposed PathoGems (PathoGenomics-based integrative survival prediction), a weakly-supervised, interpretable multimodal learning framework that integrates histology and genomic profiles for precise cancer prognosis prediction. To evaluate the robustness of PathoGems, we initially curated a dataset of 1965 cases across four cohorts from The Cancer Genome Atlas (TCGA), including breast, colorectal, glioblastoma, and esophageal cancers. For external validation, PathoGems was further evaluated on four independent cohorts, consisting of 76 breast cancer and 41 esophageal squamous cell carcinoma cases from Zhejiang Cancer Hospital, as well as 102 colorectal cancer and 58 glioblastoma cases from the Clinical Proteomic Tumor Analysis Consortium (CPTAC). RESULTS: PathoGems effectively stratified patients into favorable and unfavorable risk groups, revealing significant differences in histological patterns, genomic features, and overall survival (log-rank test, p&#x2009;<&#x2009;0.05). Moreover, the model&#x2019;s predictions are further supported by visualization and transcriptomic analysis, enhancing interpretability and reliability. CONCLUSIONS: By fusing histological and clinicogenomic multimodal models, PathoGems will provide a solid foundation for developing an innovative tool that aids clinicians in making informed decisions and selection personalized treatment strategies for cancer patients.

Humans↗
PubMed2006

Development and validation of a PulseNet standardized pulsed-field gel electrophoresis protocol for subtyping of Vibrio cholerae.

PulseNet is a network that utilizes standardized pulsed-field gel electrophoresis (PFGE) protocols with the purpose of conducting laboratory-based surveillance of foodborne pathogens. PulseNet standardized PFGE protocols are subject to rigorous testing during the developmental phase and careful evaluation during a validation process assessing its robustness and reproducibility in different laboratories. Here we describe the development and validation of a rapid PFGE protocol for subtyping Vibrio cholerae for use in PulseNet International activities. While the protocol was derived from the existing PulseNet protocol for Escherichia coli O157, various aspects of this protocol were optimized for use with V. cholerae, most notably a change of the primary and secondary restriction enzyme to SfiI and NotI, respectively, and the use of a two-block electrophoresis program. External validation of this protocol was undertaken through a collaboration between three PulseNet Asia Pacific laboratories (Public Health Laboratory Centre, Hong Kong, National Institute of Infectious Diseases, Japan, and International Center for Diarrhoeal Diseases Research-Bangladesh) and PulseNet USA. Comparison of PFGE patterns generated by each of the participating laboratories demonstrated that the protocol is robust and reproducible.

Bangladesh↗
PubMed2007

A systematic review of the quality of homeopathic pathogenetic trials published from 1945 to 1995.

BACKGROUND: The quality of information gathered from homeopathic pathogenetic trials (HPTs), also known as 'provings', is fundamental to homeopathy. We systematically reviewed HPTs published in six languages (English, German, Spanish, French, Portuguese and Dutch) from 1945 to 1995, to assess their quality in terms of the validity of the information they provide. METHODS: The literature was comprehensively searched, only published reports of HPTs were included. Information was extracted by two reviewers per trial using a form with 87 items. Information on: medicines, volunteers, ethical aspects, blinding, randomization, use of placebo, adverse effects, assessments, presentation of data and number of claimed findings were recorded. Methodological quality was assessed by an index including indicators of internal and external validity, personal judgement and comments of reviewers for each study. RESULTS: 156 HPTs on 143 medicines, involving 2815 volunteers, produced 20,538 pathogenetic effects (median 6.5 per volunteer). There was wide variation in methods and results. Sample size (median 15, range 1-103) and trial duration (mean 34 days) were very variable. Most studies had design flaws, particularly absence of proper randomization, blinding, placebo control and criteria for analysis of outcomes. Mean methodological score was 5.6 (range 4-16). More symptoms were reported from HPTs of poor quality than from better ones. In 56% of trials volunteers took placebo. Pathogenetic effects were claimed in 98% of publications. On average about 84% of volunteers receiving active treatment developed symptoms. The quality of reports was in general poor, and much important information was not available. CONCLUSIONS: The HPTs were generally of low methodological quality. There is a high incidence of pathogenetic effects in publications and volunteers but this could be attributable to design flaws. Homeopathic medicines, tested in HPTs, appear safe. The central question of whether homeopathic medicines in high dilutions can provoke effects in healthy volunteers has not yet been definitively answered, because of methodological weaknesses of the reports. Improvement of the method and reporting of results of HPTs are required. REFERENCES: References to all included RCTs are available on-line at.

Homeopathy↗
PubMed2006

Predicting individual survival after gastric cancer resection: validation of a U.S.-derived nomogram at a single high-volume center in Europe.

OBJECTIVE: Validation of a U.S.-derived nomogram for individual prediction of disease-specific gastric cancer survival at a European institution. SUMMARY BACKGROUND DATA: One major issue of modern cancer treatment is the individualization of therapy. For gastric cancer, Kattan et al, at Memorial Sloan-Kettering Cancer Center, New York, NY, developed a nomogram, allowing to predict individual patient risk of tumor-related death after R0 resection from basic patient-related variables. The validity of the nomogram has not yet been shown in patients from other institutions. The accuracy of the nomogram when applied to patients after having undergone R0 gastric cancer resection at a European high-volume center was investigated. METHODS: Clinical data from patients who underwent R0 gastric cancer resection at Klinikum rechts der Isar, Technical University of Munich, Germany and fitted the respective derivation criteria were used for external validation (n = 862). Nomogram predictions for 60- and 108-month disease-specific survival were calculated for each patient and compared with actual survival. The concordance index was used as an accuracy measure. RESULTS: The bootstrap-corrected concordance index was 0.77 and was superior when compared with the predictive ability of International Union Against Cancer tumor stage (P < 0.008). Nomogram calibration was excellent for 60-month disease-specific survival. Nomogram predictions showed the trend to underestimate survival in stage II/III disease of the MRI patients. CONCLUSIONS: The use of the nomogram created by Kattan et al is not only confined to the institution where it was created, but it can be adopted by other institutions with similar surgical strategies.

Adenocarcinoma↗
PubMed2005

Pharmacoeconomic evaluation of antidepressants : a critical appraisal of methods.

In recent years, there has been much debate regarding the real cost effectiveness of new antidepressants. This review is an attempt to identify key contentious methodological issues that can impact the reliability, validity and quality of the research on this subject. There are inherent complexities between inputs and outcomes related to depression, and the choice of pharmacoeconomic methodology requires a crucial balance between the study design and its ability to capture relevant information. Knowledge of the real efficiency of antidepressants should always be ascertained with reference to the real-world setting. Studies that show a corresponding balance between internal and external validity, coupled with sound methodology and standardised reporting, have the potential to translate pharmacoeconomics research into real-world, time-relevant decision-making.

Antidepressive Agents↗
PubMed2005

A new approach to accurate diagnosis of acute appendicitis.

This study aimed (1) to develop a simple scoring system incorporating ultrasound (US) examination and clinical or laboratory predictors for increasing diagnostic accuracy in acute appendicitis (AA), and (2) to evaluate the performance of the scoring system as compared to that of previous models. Fifteen variables including US assessment for patients admitted with suspected AA were considered in multivariate analysis using the finding of AA at operation as the end point (internal study). The new score, together with 11 previous ones, was applied to a prospective independent population of subjects with suspected AA, and the respective performances were compared (external validation study). Among 303 patients (170 males, mean age 28.3 +/- 13.3 years) of the internal study, 161 went on to surgery, and 130 had AA at operation. Four independent correlates of AA were identified and used for the derivation of the following integer-based scoring system: number of points = 6 for US demonstrating AA + 4 for tenderness in the right lower quadrant + 3 for rebound tenderness + 2 for leukocyte count >12,000/microl. In the external study (201 subjects, 105 males, mean age 28.7 +/- 11.9 years, 109 operated, 87 with AA), when the cut-off of >/or = 8 points for AA was used, sensitivity, specificity, accuracy, and area under the curve of the proposed score were 95.4%, 97.4%, 96.5%, and 93%, respectively, exceeding noticeably the previous models. The proposed scoring system introduces a quantitative combination of the clinical evaluation with US imaging and a marker of inflammatory response, which may enhance the diagnostic accuracy for subjects with suspected AA especially in geographical areas where CT scanning is not readily available on a 24-hour basis.

Acute Disease↗