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At least 793 records · Page 44Linked to original sources
PubMed2002

Development and validation of a non-linear IVIVC model for a diltiazem extended release formulation.

To develop and validate internally an in vitro-in vivo correlation (IVIVC) for a diltiazem multi-particulate bead extended release formulation. In vitro dissolution of diltiazem capsules was examined using the following methods: USP Apparatus II (paddle) at 100 rpm and USP Apparatus III at 30 dpm. Seven healthy subjects received three diltiazem formulations (90 mg): slow (S), moderate (M), fast (F) releasing and an oral solution (90 mg). Serial blood samples were collected over 48 h and analyzed by a validated HPLC assay using ultraviolet detection. The f(2) metric (similarity factor) was used to analyze the dissolution data. Linear and non-linear (quadratic, cubic, and sigmoid functions) correlation models were developed using pooled fraction dissolved (FRD) and fraction absorbed (FRA) data from various combinations of the formulations. Predicted diltiazem concentrations were obtained by convolution of the in vivo dissolution rates. Prediction errors were estimated for C(max) and AUC to determine the validity of the correlation. Apparatus II using purified water was found to be the most discriminating dissolution method. Significant intersubject (CV%>50) was observed for C(max) and AUC. The quadratic M/F IVIVC model provided a significant relationship between FRD and FRA when using either two or three of the formulations. An average percent prediction error for C(max) and AUC for all formulations was 12.4% and 9.2%, respectively. The prediction errors observed for C(max) and AUC suggest that the predictability of the quadratic IVIVC model is inconclusive, as such, external validation studies are required.

Calcium Channel Blockers↗
PubMed2001

Monotherapy trials in antiepileptic drugs: are modified "presurgical studies" a way out of the dilemma?

Monotherapy trials in epilepsy are confronted with a dilemma: either they are in conflict with ethical requirements, or they are scientifically not meaningful. Monotherapy trials, which are performed as controlled studies randomizing patients to ineffective (pseudo)placebo treatment, are incompatible with the Helsinki Declaration. On the other hand, equivalence or noninferiority studies using an active-control design do not permit valid conclusions on the efficacy of the test drug. Therefore, they do not fulfill scientific requirements for trials on new drugs. As an alternative approach, a monotherapy trial design for epilepsy patients undergoing presurgical evaluation was outlined. During presurgical evaluation, antiepileptic drugs are routinely tapered down for seizure recording. This situation is used for a placebo-controlled short-term monotherapy trial. Four trials according to this design have been completed so far. Recently, several points of concern have been raised against this design, especially for matters of ethics and external validity. In the present article, these objections are outlined and discussed. In the proposed modification the randomization and the titration of the test drug or control begins prior to the presurgical investigations. The advantages are: the test drug does not have to be titrated quickly, pure monotherapy conditions are achieved, and the subjects do not have to experience more seizures than are required for the presurgical evaluation.

Anticonvulsants↗
PubMed2006

Clinical utility of a pharmacostatistical model for ibandronate in postmenopausal osteoporosis.

Ibandronate, a potent, nitrogen-containing bisphosphonate for the treatment of postmenopausal osteoporosis, is the subject of an ongoing clinical development program to explore novel oral and intravenous (i.v.) dosing regimens. As part of this program, an extensive modeling and simulation project was undertaken to develop and validate a pharmacologically realistic mathematical model for ibandronate in osteoporosis, the aim being to identify practical dosing regimens for clinical evaluation. A simplified kinetics of drug action or kinetic-pharmacodynamic (K-PD) model (developed from a 4-compartment pharmacokinetic-pharmacodynamic [PK-PD] model) accurately described the urinary excretion of the C-telopeptide of the alpha-chain of type I collagen (uCTX). The model was extended to consider the effects of supplemental calcium therapy and allow simultaneous fitting of i.v. and oral ibandronate data, and then externally validated. This model was used successfully in the selection of appropriate once-monthly doses for further clinical evaluation and recent clinical studies have confirmed the efficacy of the doses identified. Further development of the model may include investigating the effects of ibandronate on bone mineral density and fracture risk, which would further enhance its clinical utility and predictive value. Although modeling and simulation has been used to explore the efficacy of other bisphosphonates, the extensive program with ibandronate has produced a comprehensively validated model that is the first to be prospectively tested by evaluating novel dosing regimens.

Bone Density Conservation Agents↗
PubMedDate not supplied

[Job stress in the service industry. Evaluation of the Italian version of the Job Content Questionnaire].

BACKGROUND: Recent changes in work organization have greatly expanded the service industry, where stress perception appears to be the major factor of discomfort. Job stress remains a critical issue in occupational exposure assessments. OBJECTIVES: To assess the compliance and the consistency of the three major constructs (Psychological Job Demand (PJD); Decision Latitude (DL); and Social Support at Work (SSW)) of the Italian version of the Job Content Questionnaire (JCQ) adopted in the MOPSY and JACE studies and their gender-specific distributions in a large sample of civil servant in northern Italy. METHODS: JCQ was administered to 2601 men and 5761 women employed in six different departments of the Municipality of Milan. Two JCQ versions - short and intermediate which differ by the number of items that assess DL for inclusion of SSW, were used in different sub-samples. Compliance was measured in terms of participation rate and percentage of missing items. A construct-specific Cronbach alpha coefficient was used to assess internal consistency. As a measure of external consistency the correlation coefficients between the three constructs were adopted. RESULTS: The participant rate was very high in the entire sample: 75.3% in men and 76.2% in women. The percentage of missing items was small and acceptable, ranging from 3.61% for DL to 6.33% for SSW. The Cronbach alpha coefficients ranged from 0.72 for PJD to 0.88 for SSW. Assumptions for external validity were satisfied in both gender groups. The percentage of perceived high job stress diminished in older men, but the age trend was inverse among women, indicating gender differences in the possibility of improving work conditions and career. Interferences with the family-related load and responsibilities may play a significant role. In both gender groups, a satisfactory SSW level reduced perceived high job stress. CONCLUSIONS: The adopted versions of the JCQ, originally developed in American and north European socio-cultural contexts, demonstrated satisfactory levels of compliance, and internal and external consistency. The JCQ adequately described perceived job stress in the groups of workers under study.

Adult↗
PubMed2006

Some prognostic models for traumatic brain injury were not valid.

OBJECTIVE: Various prognostic models have been developed to predict outcome after traumatic brain injury (TBI). We aimed to determine the validity of six models that used baseline clinical and computed tomographic characteristics to predict mortality or unfavorable outcome at 6 months or later after severe or moderate TBI. STUDY DESIGN AND SETTING: The validity was studied in two selected series of TBI patients enrolled in clinical trials (Tirilazad trials; n = 2,269; International Selfotel Trial; n = 409) and in two unselected series of patients consecutively admitted to participating centers (European Brain Injury Consortium [EBIC] survey; n = 796; Traumatic Coma Data Bank; n = 746). Validity was indicated by discriminative ability (AUC) and calibration (Hosmer-Lemeshow goodness-of-fit test). RESULTS: The models varied in number of predictors (four to seven) and in development technique (two prediction trees and four logistic regression models). Discriminative ability varied widely (AUC: .61-.89), but calibration was poor for most models. Better discrimination was observed for logistic regression models compared with trees, and for models including more predictors. Further, discrimination was better when tested on unselected series that contained more heterogeneous populations. CONCLUSION: Our findings emphasize the need for external validation of prognostic models. The satisfactory discrimination indicates that logistic regression models, developed on large samples, can be used for classifying TBI patients according to prognostic risk.

Area Under Curve↗
PubMedDate not supplied

Assessing the appropriateness of physician prescribing for geriatric outpatients. Development and testing of an instrument.

OBJECTIVE: In a randomized, controlled trial evaluating the impact of clinical pharmacists' consultations on physicians' prescribing decisions, a seven-member physician/pharmacist panel developed an instrument to characterize and quantify the full range of drug-prescribing problems. The instrument was tested for validity and reliability. SAMPLE: The instrument was applied in reviewing prescribing for 236 geriatric outpatients. METHODS: To ensure internal validity of the instrument, five panel meetings were devoted to reaching a consensus on procedures, categories, criteria, and scoring. Each case was evaluated independently by two reviewers and each drug in the regimen was evaluated for drug-drug interactions, dosage, schedule, allergic reactions, therapeutic duplication, use of drugs without established diagnoses, and inappropriate drugs for the patient's clinical conditions; discrepancies were adjudicated by the panel chairperson. Self-reported adverse effects of 60 study patients who were interviewed, and hospital readmissions of all study patients were used to test the external validity of the instrument. RESULTS: Inter-rater reliability improved over time, reaching a high of 97.1 percent after six months. A positive association was determined between the prescribing scores and the number of reported adverse effects (rho = 0.28, p = 0.02). Although the number of patients with drug-related hospital readmissions was too few to establish a significant association between the prescribing scores and readmissions, the findings were expected. CONCLUSIONS: Given current requirements for drug utilization reviews in hospitals, health maintenance organizations, and Medicaid programs, this instrument may prove to be very useful.

Aged↗
PubMedDate not supplied

Supervised self-organizing maps in drug discovery. 2. Improvements in descriptor selection and model validation.

The modeling of nonlinear descriptor-target relationships is a topic of considerable interest in drug discovery. We, herein, continue reporting the use of the self-organizing map-a nonlinear, topology-preserving pattern recognition technique that exhibits considerable promise in modeling and decoding these relationships. Since simulated annealing is an efficient tool for solving optimization problems, we combined the supervised self-organizing map with simulated annealing to build high-quality, highly predictive quantitative structure-activity/property relationship models. This technique was applied to six data sets representing a variety of biological endpoints. Since a high statistical correlation in the training set does not indicate a highly predictive model, the quality of all the models was confirmed by withholding a portion of each data set for external validation. Finally, we introduce new cross-validation and dynamic partitioning techniques to address model overfitting and assessment.

Algorithms↗
PubMed2003

Multinational study of reliability and validity of the King's Health Questionnaire in patients with overactive bladder.

OBJECTIVE: Overactive bladder (OAB) has substantial impact on health-related quality of life (HRQoL). The purpose of this research was to evaluate the psychometric properties of the King's Health Questionnaire (KHQ). METHODS: The KHQ (n = 1284) was administered at baseline and 12 weeks post-treatment in a multinational, double-blind, randomized clinical trial of tolterodine for treatment of OAB. Country-specific psychometric analyses of HRQoL instruments were performed. Countries demonstrating marginal psychometric properties on the KHQ were pooled with same-language countries, re-evaluated, and aggregate analysis performed on the pooled data. RESULTS: Internal consistency of the KHQ was high, item characteristics were good, most assumptions of summed scales were met, and it is externally valid and consistent. Few problems with the KHQ were noted although the performance of the personal relationships domain was complicated by the 'not applicable' response category. CONCLUSIONS: Psychometric testing supports the reliability and validity of the KHQ as an OAB-specific measure of HRQoL.

Aged↗
PubMed2004

Prediction of resting energy expenditure in a large population of obese children.

BACKGROUND: Recommendations for energy intake in obese children rely on accurate methods for measuring energy expenditure that cannot be assessed systematically. OBJECTIVE: The aim was to establish and validate new equations for predicting resting energy expenditure (REE), specifically in obese children. DESIGN: REE (indirect calorimetry) and body composition (bioelectrical impedance analysis) were measured in 752 obese subjects aged 3-18 y. The first cohort (n=471) was used to establish predictive equations, the second (and independent) cohort (n=211) was used to validate these equations, and the third cohort, a follow-up group of children who lost weight (n=70), was used to examine predictive REE in the postobese period. REE values predicted with the use of various published equations and the new established equation were compared with measured REE by using the Bland-Altman method and Student's t tests. RESULTS: In cohort 1, significant determinants of the new prediction equations were fat-free mass in boys (model R2=0.79) and age and fat-free mass in girls (model R2=0.76). External validation conducted by using the Bland-Altman method and Student's t tests, in cohort 2, showed no significant difference between measured REE and predicted REE with the new equation. When already published equations were applied, systematical bias appeared with all published equations except for that of the World Health Organization. In cohort 3, the children who lost weight, almost all equations significantly underestimated REE. CONCLUSIONS: These new predictive equations allow clinicians to estimate REE in an obese pediatric population with sufficient and acceptable accuracy. This estimation may be a strong basis for energy recommendations in childhood obesity.

Adolescent↗
PubMed2006

Classification of patients with whiplash associated disorders (WAD): reliable and valid subgroups based on the Multidimensional Pain Inventory (MPI-S).

BACKGROUND: Classification of patients with chronic whiplash associated disorders (WAD) into homogenous subgroups is an important objective in order to tailor interventions and to control for subgroup differences when evaluating treatment outcome. AIMS: The aims of this study were to investigate if it was possible to replicate and describe the three cluster solution and profiles found in other pain groups and describe cluster profiles based on self-reported Multidimensional Pain Inventory-scores for patients with WAD three months after the injury, describe characteristics of the clusters in relation to disability, self-efficacy and coping at the same point in time and to validate the cluster solution by comparing clusters in disability, self-efficacy and coping over time. METHODS: Ninety-one WAD-patients three months after the accident took part in the study. The measures used were the Multidimensional Pain Inventory-Swedish version (MPI-S), The Self-Efficacy Scale, The Coping Strategies Questionnaire and The Pain Disability Index. Cluster analysis was conducted for the total sample MPI-S subscale scores. RESULTS: The adaptive copers cluster represented 42% of the sample, dysfunctional 34% of the sample, and interpersonally distressed 24% of the sample. The external validation of cluster solution showed that there were several significant differences between clusters in self-efficacy, disability and coping measures. There was also a significant interaction effect (clusterxtime) in disability (PDI). Patients in dysfunctional cluster reported a decreased disability over time. CONCLUSIONS: These results support the presence of different subgroups among patients with whiplash associated disorders. This classification can be seen as a complement to a classification based on medical condition.

Adaptation, Psychological↗
PubMed2000

A risk score to predict need for treatment for upper-gastrointestinal haemorrhage.

BACKGROUND: Current risk-stratification systems for patients with acute upper-gastrointestinal bleeding discriminate between patients at high or low risks of dying or rebleeding. We therefore developed and prospectively validated a risk score to identify a patient's need for treatment. METHODS: Our first study used data from 1748 patients admitted for upper-gastrointestinal haemorrhage. By logistic regression, we derived a risk score that predicts patients' risks of needing blood transfusion or intervention to control bleeding, rebleeding, or dying. From this score, we developed a simplified fast-track screen for use at initial presentation. In a second study, we prospectively validated this score using receiver operating characteristic (ROC) curves--a measure of the validity of a scoring system--and chi2 goodness-of-fit testing with data from 197 patients. We also validated the quicker screening tool. FINDINGS: We calculated risk scores from patients' admission haemoglobin, blood urea, pulse, and systolic blood pressure, as well as presentation with syncope or melaena, and evidence of hepatic disease or cardiac failure. The score discriminated well with a ROC curve area of 0.92 (95% CI 0.88-0.95). The score was well calibrated for patients needing treatment (p=0.84). INTERPRETATION: Our score identified patients at low or high risk of needing treatment to manage their bleeding. This score should assist the clinical management of patients presenting with upper-gastrointestinal haemorrhage, but requires external validation.

Blood Pressure↗
PubMed2025

Automated Deep Learning-Based Detection of Early Atherosclerotic Plaques in Carotid Ultrasound Imaging.

BACKGROUND: Carotid plaque presence is associated with cardiovascular risk, even among asymptomatic individuals. While deep learning has shown promise for carotid plaque phenotyping in patients with advanced atherosclerosis, its application in population-based settings of asymptomatic individuals remains unexplored. METHODS: We developed a YOLOv8-based model for plaque detection using carotid ultrasound images from 19,499 participants of the population-based UK Biobank (UKB) and fine-tuned it for external validation in the BiDirect study (N = 2,105). Cox regression was used to estimate the impact of plaque presence and count on major cardiovascular events. To explore the genetic architecture of carotid atherosclerosis, we conducted a genome-wide association study (GWAS) meta-analysis of the UKB and CHARGE cohorts. Mendelian randomization (MR) assessed the effect of genetic predisposition to vascular risk factors on carotid atherosclerosis. RESULTS: Our model demonstrated high performance with accuracy, sensitivity, and specificity exceeding 85%, enabling identification of carotid plaques in 45% of the UKB population (aged 47-83 years). In the external BiDirect cohort, a fine-tuned model achieved 86% accuracy, 78% sensitivity, and 90% specificity. Plaque presence and count were associated with risk of major adverse cardiovascular events (MACE) over a follow-up of up to seven years, improving risk reclassification beyond the Pooled Cohort Equations. A GWAS meta-analysis of carotid plaques uncovered two novel genomic loci, with downstream analyses implicating targets of investigational drugs in advanced clinical development. Observational and MR analyses showed associations between smoking, LDL cholesterol, hypertension, and odds of carotid atherosclerosis. CONCLUSIONS: Our model offers a scalable solution for early carotid plaque detection, potentially enabling automated screening in asymptomatic individuals and improving plaque phenotyping in population-based cohorts. This approach could advance large-scale atherosclerosis research.

atherosclerosis↗
PubMed1993

Reliability and validity of an infant gastroesophageal reflux questionnaire.

To improve history-taking of infants with suspected gastroesophageal reflux, we developed an Infant Gastroesophageal Reflux Questionnaire consisting of 161 items covering demographics, symptoms (regurgitation, weight deficit, respiratory difficulties, fussiness, apnea, and pain or bleeding of esophagitis), and possible causes (feeding volume and frequency, allergy, infection, colic, central nervous system abnormalities, positioning, and smoke exposure). The questionnaire was completed by primary caretakers of 69 infants aged 1 to 58 weeks suspected of having reflux. Median time to complete the questionnaire was 20 minutes. The median internal consistency of 29 pairs of redundant questions was 0.94. Median test-retest consistency of 110 items for nine respondents was 0.88. Median interobserver consistency, evaluated for 129 items in 35 questionnaires also filled out by secondary caretakers, was 0.85. The median accuracy of four externally validated items was 1.00. This questionnaire can aid pediatricians in making decisions regarding diagnoses and treatment in this common but complex disorder.

Airway Obstruction↗
PubMed1999

Validation of the Chinese-Cantonese version of the hospital anxiety and depression scale and comparison with the Hamilton Rating Scale of Depression.

OBJECTIVE: The aim of this study was to validate the Chinese-Cantonese version of the Hospital Anxiety and Depression Scale (HADS) and to compare it with the Hamilton Rating Scale of Depression (HRSD) as a screening tool for depressive disorders in general hospital in-patients. METHOD: The Chinese-Cantonese version of the HADS was administered to general hospital in-patients seen on a consultation basis, and psychiatric diagnoses were made according to DSM-III-R. The subjects were further rated independently with the HRSD. RESULTS: The Chinese-Cantonese version of the HADS was found to have good internal consistency and external validity, with favourable sensitivity and specificity for screening for psychiatric disorders. However, its performance was marginally inferior to that of the HRSD. The scale also performed poorly in identifying major depression. CONCLUSION: The HADS has limitations with regard to identification of depressive disorders. However, despite its shortcomings, it remains one of the best paper-and-pencil tests for screening psychiatric disorders in the medically ill.

Adult↗
PubMed2005

Application of validated QSAR models of D1 dopaminergic antagonists for database mining.

Rigorously validated quantitative structure-activity relationship (QSAR) models have been developed for 48 antagonists of the dopamine D1 receptor and applied to mining chemical datasets to discover novel potential antagonists. Several QSAR methods have been employed, including comparative molecular field analysis (CoMFA), simulated annealing-partial least squares (SA-PLS), k-nearest neighbor (kNN), and support vector machines (SVM). With the exception of CoMFA, these approaches employed 2D topological descriptors generated with the MolConnZ software package (EduSoft, LLC. MolconnZ, version 4.05; http://www.eslc.vabiotech.com/ [4.05], 2003). The original dataset was split into training and test sets to allow for external validation of each training set model. The resulting models were characterized by cross-validated R2 (q2) for the training set and predictive R2 values for the test set of (q2/R2) 0.51/0.47 for CoMFA, 0.7/0.76 for kNN, R2 for the training and test sets of 0.74/0.71 for SVM, and training set fitness and test set R2 values of 0.68/0.63 for SA-PLS. Validated QSAR models with R2 > 0.7, (i.e., kNN and SVM) were used to mine three publicly available chemical databases: the National Cancer Institute (NCI) database of ca. 250,000 compounds, the Maybridge Database of ca. 56,000 compounds, and the ChemDiv Database of ca. 450,000 compounds. These searches resulted in only 54 consensus hits (i.e., predicted active by all models); five of them were previously characterized as dopamine D1 ligands, but were not present in the original dataset. A small fraction of the purported D1 ligands did not contain a catechol ring found in all known dopamine full agonist ligands, suggesting that they may be novel structural antagonist leads. This study illustrates that the combined application of predictive QSAR modeling and database mining may provide an important avenue for rational computer-aided drug discovery.

Databases, Factual↗
PubMed2002

[Validation of ESCAP-CD as an instrument of measure for the evaluation of the quality of life in prostatic cancer. Part 2a].

UNLABELLED: In order to make a measure of quality of life related to health (QLRH) useful in the investigation, it must fulfill the psychometric properties (validity, reliability and sensibility). The selection of an instrument is a job for the clinic that must choose the most effective for each proposed objective. We set out the objectives to validate the ESCAP-CDV in a multicentric study in Andalusia. We studied 88 patients who were submitted to the instrument presented to validation and two more tests recognized already: the QLQ-C30 from EORTC gold standard in Europe in the valuation of the neoplastic patients' quality of life and the KARNOFSKY the most clinic utility index in neoplastic patients, used to correlate the items. RESULTS: Questionnaire acceptance analysis: The difficulty of understanding was greater for QLQ C30 items (6.81%) than ESCAP items (1.98%). The lapse of time needed to carry out the test was shorter in the ESCAP test (9.84 min) than in the QLQ C30 (13.13), test. Structural analysis or internal validity analysis: The homogeneity index of the items is high (alfa of Cronbach = 0.93). The dimensionality proposed is not accepted, due to the existence of some modifications pund in the factorial analysis. Finally, the established dimensions: Physical and Emotional Capacity (PEC), 5 items; General Symptoms (GS), 4 items; Pain (P), 3 items; Ligh Functional Capcity (LFC), 4 items; Serious Functional Capacity (SFC), 2 items; Economic State (ES), 3 items; Social and Family State (SFE), 5 items; Capacity Sexual (CSX), 2 items; Isolated Variables (IV), 2 items; and Specific Questionnaire (P), 6 items. The ESCAP is a scale with a normal distribution. Approach or external validity analysis: The ESCAP test is well correlated with the other two scales. Reliability test retest: The interclass correlation coefficient is 0.94 in the ESCAP, not so in the KARNOFSKY that is 0.77. CONCLUSIONS: The ESCAP-CDV is a new instrument of valuation of the QLRH composed of a general questionnaire and other specific test of prostate cancer. It has turned out to be a very homogeneous scale due to its internal consistence (alfa of Cronbach of 0.93), showing that it has a normal distribution, that correlates correctly with the scales compared and it is a valid scale to measure the prostate cancer patients' quality of life. The ESCAP-CDV has shown to be a scale with a high reliability (0.94), setting up as an instrument not only useful for investigation, but to clinical use, as well.

Humans↗
PubMed1997

Reports of dieting among children: effects of interview style and approach to information collection.

Recent reports have suggested that worrying about getting fat, and restrictive eating practices have been identified among pre-pubescent girls. This study sought to examine the extent to which interviewing styles and question or response types would differentially affect such reports about dieting among 40 third- and 40 sixth-grade girls. When these girls were asked if they had dieted, or if they intended to go on a diet in the future, the information-eliciting strategies interacted in different ways for the younger and older girls. As an external validation of their body-related attitudes, a second aim was to replicate Huon, Morris & Brown's (1990) body size preference study with children. Few girls identified the very thin body as their 'ideal', and their choices were not consistent with the claim that they might be dissatisfied with their body.

Body Image↗
PubMed2006

A health economic model to determine the long-term costs and clinical outcomes of raising low HDL-cholesterol in the prevention of coronary heart disease.

OBJECTIVES: The aim of this study was to describe a health economic model developed to project lifetime clinical and cost outcomes of lipid-modifying interventions in patients not reaching target lipid levels and to assess the validity of the model. METHODS: The internet-based, computer simulation model is made up of two decision analytic sub-models, the first utilizing Monte Carlo simulation, and the second applying Markov modeling techniques. Monte Carlo simulation generates a baseline cohort for long-term simulation by assigning an individual lipid profile to each patient, and applying the treatment effects of interventions under investigation. The Markov model then estimates the long-term clinical (coronary heart disease events, life expectancy, and quality-adjusted life expectancy) and cost outcomes up to a lifetime horizon, based on risk equations from the Framingham study. Internal and external validation analyses were performed. RESULTS: The results of the model validation analyses, plotted against corresponding real-life values from Framingham, 4S, AFCAPS/TexCAPS, and a meta-analysis by Gordon et al., showed that the majority of values were close to the y = x line, which indicates a perfect fit. The R2 value was 0.9575 and the gradient of the regression line was 0.9329, both very close to the perfect fit (= 1). CONCLUSIONS: Validation analyses of the computer simulation model suggest the model is able to recreate the outcomes from published clinical studies and would be a valuable tool for the evaluation of new and existing therapy options for patients with persistent dyslipidemia.

Cholesterol, HDL↗