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Subject attrition in prevention research.

Subject attrition threatens the internal validity of substance abuse prevention studies because differences in the rate of attrition and the substance use behavior of remaining subjects in the different conditions could account for any differences found in substance use rates. Attrition threatens the external validity of prevention studies because, to the extent that study dropouts are different from remaining subjects, the results of the study may not be generalizable to study dropouts. Analysis of these threats to the validity of prevention studies should be routinely conducted. However, studies of alcohol and drug abuse prevention have generally failed to report or analyze subject attrition. Smoking prevention studies have more frequently reported attrition, and they have recently begun to analyze the degree to which attrition may affect the internal and external validity of the study. Evidence thus far suggests that differences in attrition across conditions do occur occasionally. The evidence is substantial that study dropouts are systematically more likely to smoke, to use other substances, and to score highly on other risk-taking measures.

Alcoholism↗

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

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

Colitis, Ulcerative↗

Research progress and application prospects of multi-omics integration strategies in precision risk stratification of type 1 diabetes mellitus.

Type 1 diabetes (T1D) is a chronic metabolic disease mediated by autoimmunity. Its pathogenesis involves complex interactions between genetic susceptibility and environmental factors. Conventional T1D risk stratification primarily relies on genetic markers, islet autoantibodies, and glycemic indicators. Although these biomarkers remain indispensable in current clinical practice, they are often insufficient when used alone to accurately identify ultra-early high-risk individuals, predict disease progression rates, or support individualized preventive strategies. Consequently, more comprehensive molecular approaches are needed to improve precision risk stratification. In recent years, the rapid development of multi-omics technologies has provided new strategies for precise risk stratification of T1D. This narrative review critically evaluates how multi-omics integration strategies can improve precision risk stratification throughout the T1D disease continuum by integrating complementary molecular information from genomics, transcriptomics, proteomics, metabolomics, epigenomics, and the microbiome. Particular emphasis is placed on stage-specific biomarker discovery, multi-omics data integration frameworks, artificial intelligence-assisted prediction models, biomarker validation, and the opportunities and challenges associated with clinical translation. Current evidence suggests that integrated multi-omics approaches have the potential to improve risk prediction accuracy, distinguish heterogeneous disease trajectories, identify individuals at imminent risk of progression, and provide biologically informed targets for precision intervention. However, important challenges remain, including data harmonization, external validation, model interpretability, cost-effectiveness, and integration into routine clinical screening programs. Future research should prioritize prospective multicenter cohorts, standardized analytical pipelines, externally validated prediction models, and clinically interpretable multi-omics frameworks to facilitate the translation of precision risk stratification into routine T1D prevention and management.

Humans↗

Cyclophosphamide versus methylprednisolone for the treatment of neuropsychiatric involvement in systemic lupus erythematosus.

BACKGROUND: Neuropsychiatric involvement in systemic lupus erythematosus is complex and several clinical presentations are related to this disease such as: convulsions, chronic headache, transverse myelitis, vascular brain disease, psychosis and neural cognitive dysfunction. OBJECTIVES: To assess the efficacy and safety of cyclophosphamide and methylprednisolone in the treatment of neuropsychiatric manifestations of systemic lupus erythematosus on mortality and side effects. SEARCH STRATEGY: We searched EMBASE, LILACS, Cochrane Controlled Trials Register and MEDLINE up to and including December 1999, additional articles were sought through handsearching in relevant journals, using the search strategy described in the Cochrane Handbook [Dickersin 1994]. There were no language restrictions. SELECTION CRITERIA: All randomized controlled trials which compared cyclophosphamide to methylprednisolone were to be included. Patients of any age and gender were included if they fulfilled the criterion of the American Rheumatology Association for the diagnosis of systemic lupus erythematosus and presented with any one of the following neuropsychiatric events; convulsions, organic brain syndrome; cranial neuropathy. Outcome measures included the following: a) Overall mortality (primary event); b) Motor and psychiatric deficit (primary event); c) Clinical improvement (secondary event). DATA COLLECTION AND ANALYSIS: The analysis planned was to do the following: Data would be independently extracted by the two reviewers and cross-checked. The methodological quality of each trial would be assessed by the same two reviewers. Details of the randomisation (generation and concealment), blinding, and the number of patients lost on follow-up would be recorded. The results of each RCT would be summarised on an intention-to-treat basis in 2 x 2 tables for each outcome. External validity would be defined by characteristics of the participants, the interventions and the outcomes. If appropriate, RCTs would be stratified based on control group and category of disease in accordance to the clinical homogeneity (external validity). The results obtained from these different methods are very similar, and therefore, only the results from the Risk Difference method, with the corresponding 95% confidence interval would be presented in this review. The fixed effects model would be used if there was no significant statistical heterogeneity. MAIN RESULTS: We found no randomised controlled trials comparing cyclophosphamide versus methylprednisolone for the treatment of neuropsychiatric involvement in the systemic lupus erythematosus. REVIEWER'S CONCLUSIONS: Cyclophosphamide regimen treatment is a form of care in neuropsychiatric involvement in systemic lupus erythematosus with no evidence to prove better effectiveness and safety when compared with methylprednisolone. This systematic review found no randomised controlled trials and its findings must be interpreted as 'no evidence of effect' and not as 'evidence of no effect'.

Antirheumatic Agents↗

Ensemble DNA methylation clock demonstrates Immune-metabolic aging signatures associated with mortality.

Aging is a multifactorial process that is best described in terms of the progressive acquisition of multiple layers of phenotypic changes, such as epigenetic modifications, inflammation, and metabolic dysregulation. DNA methylation clocks have been extensively used to construct epigenetic clocks based on the DNAm profiles that can be used to estimate biological age and predict age-associated outcomes. Nevertheless, the vast majority of clocks constructed so far have been based on linear models, which are unlikely to fully account for the heterogeneity and non-linearity of survival-related DNAm signatures. In this work, we constructed a heterogeneous stacked ensemble survival model based on DNAm data obtained from the Framingham Heart Study. We first identified 190 CpG loci using elastic net Cox regression and subsequently constructed a survival prediction model based on the fusion of five complementary survival models by means of a neural network meta-learner. The prediction power of the survival model was evaluated in an external validation cohort, where we observed strong performance for predicting all-cause mortality that significantly exceeded PhenoAge and was statistically comparable to GrimAge. These performance estimates were derived in cohorts of European ancestry and externally validated in postmenopausal women aged 50-79 years, and should therefore be interpreted as applicable only to demographically similar populations.

Humans↗

The reliability of upper limb anthropometry in older Chinese people.

OBJECTIVE: To evaluate the validity of the Durnin-Womersley equations and to derive our local predictive equations for body fat from upper limb skinfold thicknesses in older Chinese people in Hong Kong. To evaluate the validity of mid-arm circumference and corrected arm muscle area in predicting lean tissue mass in the same population. DESIGN: Comparison of fat percentages predicted by Durnin-Womersley (D-W) equations with those estimated by Dual energy X ray absorptiometry (DXA). Predictive equations derived from regression between upper limb skinfold thicknesses and fat percentages estimated by DXA were similarly evaluated in internal and external validation groups. Mid-arm circumference (MAC) and corrected arm muscle area (CAMA) were correlated with the limb lean tissue mass, body lean tissue mass and fat percentage. SUBJECTS: 354 female and 263 male, apparently well, community dwelling subjects, aged 69-82 y; of which 40 subjects of each sex were randomly selected from the study population for internal validation of the local predictive equations; 60 female and 33 male hospital medical outpatients, aged 61-87 y, were recruited for external validation. MEASUREMENTS: Triceps and biceps skinfold thicknesses, mid-arm circumference, body mass index, fat percentages, limb and whole body lean tissue masses estimated by Hologic QDR-2000 bone densitometer. RESULTS: Fat percentages calculated by D-W equations were significantly different from those estimated by DXA (average difference -2.4 (s.d. 4.8)% and +2.1 (5.2)% in females and males respectively). The corresponding differences for our local predictive equations were not significant (-0.9 (4.7)% and -0.5 (5.0)% in females and males respectively). There was a trend of under-estimation of body fat with increasing fatness. In the hospital medical outpatients, there was a significant difference between fat percentages predicted by our equation and those by DXA in female (-2.9(5.3)%), but not in male (+0.3(4.3)%) subjects. In males, MAC correlated with limb and body lean tissue masses as well as with fat percentage (r = 0.60, 0.68, 0.65 respectively). CAMA correlated similarly well with lean tissue masses but was more independent of fat percentage (r = 0.61, 0.65, 0.44 respectively). In females, both MAC and CAMA correlated poorly with limb and body lean tissue masses. Moreover, MAC correlated well with fat percentage (r = 0.80). CONCLUSION: Upper limb skinfold thicknesses measurement is a valid means of predicting body fat in older Chinese people. Local predictive equations were more reliable that D-W equations. They were, however, subject to errors at the extreme ends of body fatness and in the presence of disease. In older females, MAC and CAMA were not reliable in predicting lean tissue mass, but MAC could be used to predict fat percentages. In older males, CAMA was more reliable than MAC in predicting lean tissue mass.

Absorptiometry, Photon↗

Detection of depressive symptomatology in elderly people: a short version of the CES-D scale.

This study aims to test a short form of the Center for Epidemiological Studies--Depression Scale (CES-D) which can be a useful screening tool for depressive symptomatology in epidemiological studies of elderly patients. The study was conducted on 2792 subjects from the PAQUID (Personnes Agées QUID?) cohort, an epidemiological survey of community dwellers living in South-West France. CES-D items with high sensitivity and good specificity were selected for the short form, then the best cut-off scores were determined with Receiver Operating Characteristics (ROC) curves. The external validity of the 5-item scale was then assessed against the full scale at different PAQUID follow-ups. Sensitivity was 99% and specificity 81% for detecting depressive symptomatology when compared to the 20-item scale. The external validity on the different follow-ups was good, yielding a sensitivity varying from 95 to 100%, and a specificity from 83 to 89%. In conclusion, the 5-item CES-D is a simple, rapid and reliable tool which could be useful for screening depressive symptoms in epidemiological studies of the elderly.

Aged↗

Five-factor model of schizophrenic psychopathology: how valid is it?

Aim of the study was to examine the consistency of the five-factor model of schizophrenic symptoms, assess its validity and evaluate its dimensional factor structure using confirmatory factor (CFA) analysis. A sample of 258 randomly assigned DSM-III R patients with schizophrenic disorders were studied by means of the structured clinical interview for the Greek validated Positive and Negative Syndrome Scale (PANSS) and were rated on its 30 items. Patients' scores were subjected to principal component analysis (PCA) with varimax rotation. Internal consistency for each of the components was determined by the use of Cronbach's alpha. External validity of the model derived was investigated by searching for possible relationships between the components and sociodemographic characteristics with the aid of canonical correlation analysis. Confirmatory factor analysis (CFA) was also performed. Using the scree plot criterion PCA revealed a five-factor model. These factors were interpreted as representing--in a decreasing order of relative importance--the following dimensions of schizophrenic psychopathology: negative, excitement, depression, positive and cognitive impairment. The model was comparable with six previous factor analytic studies. Internal consistency was quite satisfactory whereas external validity was found to be not so powerful. CFA did not show that the proposed model yields an adequate factor structure.

Adult↗

Catecholaminergic polymorphic ventricular tachycardia mediated by ryanodine receptor 2: a validated risk stratification.

BACKGROUND AND AIMS: Patients with catecholaminergic polymorphic ventricular tachycardia (CPVT) are at risk for potentially life-threatening arrhythmic events (AEs) even while treated with β-blockers. The aim was to develop a model for individualized prediction of AEs in patients with RYR2-mediated CPVT on β-blocker monotherapy. METHODS: The derivation and independent validation cohorts included 743 and 129 patients, respectively. AEs were defined as arrhythmic syncope, appropriate implantable cardioverter-defibrillator shock, sudden cardiac arrest (SCA), and sudden cardiac death. Near-fatal or fatal AEs (nf/fAEs) included all AEs except for arrhythmic syncope. Prediction models using Cox regression were developed and internally and externally validated. RESULTS: A total of 102 (13.7%) patients in the derivation cohort and 24 (18.6%) patients in the validation cohort experienced ≥1 AE over a median follow-up of 5.1 [interquartile range (IQR), 7.7] and 2.4 (IQR, 4.4) years, respectively. Predictors of AE were arrhythmic syncope or SCA prior to diagnosis and age at β-blocker initiation. In the derivation and validation cohorts, the optimism-corrected C-indices of the models for AE were 0.67 [95% confidence interval (CI) 0.62-0.72] and 0.59 (95% CI 0.48-0.71), respectively. For nf/fAEs, ventricular arrhythmia severity before β-blocker initiation was a fourth independent predictor, and C-indices of the models in the derivation and validation cohorts were 0.74 (95% CI 0.68-0.80) and 0.60 (95% CI 0.47-0.72), respectively. In the derivation cohort, calibration slopes were 1.00 (95% CI 0.59-1.41) for AE and 1.00 (95% CI 0.69-1.32) for nf/fAE. CONCLUSIONS: These externally validated risk prediction models using clinical parameters accurately distinguished CPVT patients on β-blocker monotherapy at low and high risk for future AEs while treated with β-blockers. These models provide guidance for implementation of clinical management therapies to prevent AEs in patients with CPVT.

Humans↗

Die Vision einer pragmatischen klinischen Forschung oder das Ende der Diskussion über < > und < >

The Concept of Pragmatic Clinical Research or the End of Discussion about 'Placebo' and 'Specific Effects&rsquoThe reorientation of clinical research towards the questions of treatment benefit (beyond the question of treatment efficacy) and of how much clinical trials represent actual practice (external validity) is the timely path to clinical research questions of real interest and importance. Postmodern 'anything goes' makes it possible to also consider thus far looked down on placebo effects as valuable, however, it requires the precise documentation of the external validity of such effects. Not disease as such, but the disease context, not therapy as such, but the therapy context, not the patient as such, but the patient context, not a test as such, but the test situation have become the important focuses of clinical research. In respect to test results current medicine has to recognize its illiterate mystification of allegedly 'objective' and 'hard' data. The patient context can determine whether an 'efficacious' therapy is beneficial or harmful, and thus, it is the proper definition of the patient context which makes medicine scientific, no matter how 'objective' or 'subjective' the effect of therapy is. The consideration of the therapy context leads to the important distinction between efficacy and effectiveness (or benefit), and it becomes intelligible that the randomised controlled trial in its traditional design as the placebo-controlled double-blind trial is limited to the evaluation of an agent theory. The evaluation of treatment effectiveness requires more pragmatic trials which study treatment operations and not isolated components and which may even compare entire treatment strategies. Pragmatic clinical trials, in future, will not only allow the study of 'pathogenesis blockers'., but also the study of 'salutogenetic' interventions working with the formation of the host. The focus of attention and research in the new school of evidencebased medicine with clinical epidemiology as its basic science (if not superficially understood as mere literature medicine) has long ago been identified as illness as the product of host, disease and environment. The dispute about 'placebo' and 'specific effects', in the meantime, has become obsolete.

Journal Article↗

Meaning in life depth in the active married elderly.

To discover if elderly people have developed a deeper meaning in life than younger individuals, a sample of active married elderly people was compared to a group of younger adults. Two dimensions of meaning in life depth were investigated. The first was a self-suitability measure indicating comfort with one's own meaning, measured by Crumbaugh and Maholick's (1969) Purpose in Life Test. The second was an external validation measure derived from a statement about their own strongest meaning in life, written by the participants and rated for depth by two outside judges. The older group scored significantly higher than the younger adults on the self-suitability measure and significantly lower on the external validation measure. Such results could mean that toward the end of life we are better able to appreciate life's beauty though less able to communicate our depth of appreciation to others. An alternative interpretation of the results is that the elderly participants were engaging in self-deception.

Aged↗

An Exosomal Signature for Preoperative Detection of Occult Liver Metastasis in Pancreatic Cancer.

IMPORTANCE: Early liver metastasis (early-LiM) after pancreatectomy represents an aggressive biological phenotype of pancreatic ductal adenocarcinoma (PDAC) and is associated with markedly poor survival. Reliable preoperative biomarkers to identify occult hepatic micrometastasis remain lacking. OBJECTIVE: To develop and externally validate a circulating exosomal microRNA (exo-miRNA)-based machine learning model for preoperative detection of occult early-LiM in PDAC. DESIGN, SETTING, AND PARTICIPANTS: This multicenter retrospective case-control study included 3 phases: genome-wide discovery using exo-miRNA sequencing (discovery cohort), model development (training cohort), and independent external validation (2 validation cohorts). The study took place at 4 medical centers in China, Japan, and South Korea. A total of 372 patients were enrolled between 2011 and 2024. Data were analyzed from July 2024 to November 2025. EXPOSURES: Circulating plasma-derived exosomal miRNA expression profiles. MAIN OUTCOMES AND MEASURES: The primary outcome was early-LiM, defined as liver recurrence within 6 months after curative-intent resection. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC) and survival outcomes were assessed using Kaplan-Meier analysis. RESULTS: Among 372 patients with PDAC (median [IQR] age, 67 [59-73] years; 229 [61.6%] male and 143 [38.4%] female; median follow-up among survivors, 969 days),early-LiM was associated with significantly worse overall survival compared with other recurrence patterns (median OS, 9.1 months vs 26.6-31.8 months; log-rank P&#x2009;<&#x2009;.001). A 7-exo-miRNA extreme gradient boosting model demonstrated discrimination in the training cohort (AUC, 0.899; 95% CI, 0.822-0.976) and maintained performance in external testing cohorts (AUC, 0.876; 95% CI, 0.846-0.951 and AUC, 0.862; 95% CI, 0.744-0.981). The exo-miRNA panel score remained an independent identifier of early-LiM in multivariable analysis (odds ratio, 26.49; 95% CI, 18.45-55.28; P&#x2009;<&#x2009;.001) and stratified overall survival (log-rank P&#x2009;<&#x2009;.001). Decision curve analysis suggested improved net clinical benefit compared with conventional clinicopathologic variables. CONCLUSION AND RELEVANCE: In this multicenter study, a circulating exo-miRNA-based machine learning model enabled preoperative detection of occult early liver metastasis risk in PDAC. These findings support the potential of exosomal biomarkers to inform biology-guided treatment sequencing and warrant prospective validation.

Journal Article↗

Threats to the validity of clinical trials employing enrichment strategies for sample selection.

Subject selection and exclusion criteria employed in typical clinical effectiveness trials of investigational new drugs have two fundamental aims: (1) to ensure that patients entering a study are truly suffering from the condition the drug is intended to treat and (2) to maximize the likelihood that the study will detect an effect of the drug if, in fact, one exists. Typical protocol selection criteria not only specify exacting procedures for establishing and documenting the diagnosis of those recruited for a study but also seek to increase, relative to the prevalence in the general population, the proportion of individuals in the sample likely to respond to pharmacological treatment. Because it is ordinarily impossible to learn prior to extensive clinical experience with a new drug which, if any, patient characteristics reliably predict a consistent treatment response, strategies for sample "enrichment" typically operate by excluding patients (for example, those with very advanced and/or complicated illness, those with serious concomitant illness, those at the extremes of age, those with very mild illness, and so forth) in whom a dependable response to treatment seems unlikely on logical and/or generic grounds. Some studies use positive strategies for sample "enrichment." In studies evaluating drugs intended to treat recurrent episodes of psychiatric illnesses, many protocols recommend selective recruitment of patients with a history of meaningful positive responses to antipsychotic treatment during prior episodes. Sample selection procedures of these kinds impose limits on the generalizability of a study's results (i.e., external validity), but the use of nonrandom patient samples is ordinarily held to have no effect on the internal validity of the results. In short, studies employing highly selected patient samples are, despite their limited external validity, regularly accepted as valid sources of evidence bearing on a drug's effectiveness. There are exceptions, however; this paper describes one in which the use of a seemingly innocuous sample enrichment maneuver proved highly damaging to the ultimate credibility of an important multicenter trial. In particular, exposure to an experimental treatment during an open qualification phase may invalidate drug-placebo comparisons made during a later randomized, blinded, controlled phase. Our review of the trial also reveals that the enrichment maneuver employed probably failed to accomplish its intended aims, selecting patients whose improvements on the outcome variable may be as reasonably ascribed to chance as to drug effect. This is all the more surprising because the method of sample enrichment employed has much in common with those long recommended in the clinical trial literature.

Aged↗

Machine learning vs. traditional methods for predicting postoperative cardiac complications after non-cardiac surgery: a systematic review and Bayesian network meta-analysis.

INTRODUCTION: Accurate prediction of peri-operative cardiac complications is critical to optimise pre-operative decision-making. Traditional risk prediction scores, such as the Revised Cardiac Risk Index, show only modest discrimination. Machine learning can model complex, non-linear relationships but their predictive performance compared with traditional scores remains unclear. METHODS: We performed a systematic review and Bayesian network meta-analysis. The primary outcome was postoperative adverse cardiac events following non-cardiac surgery. Prediction models were assessed relative to the Revised Cardiac Risk Index. As many studies evaluated multiple versions of each model type, the highest performing ('best version') and lowest performing ('worst version') results were analysed. Models were ranked using the surface under the cumulative ranking curve (SUCRA). RESULTS: Thirteen studies evaluating 54 models and 927,113 patients were included. Machine learning approaches generally outperformed traditional risk scores. Automated machine learning ranked highest (SUCRA 96.6) showed the greatest improvement in the best version analysis (mean difference (MD) 0.28 (95%CrI 0.16-0.40)) and remained superior in the sensitivity analysis (MD 0.30 (95%CrI 0.14-0.45)). Gradient boosting models showed superior performance over the Revised Cardiac Risk Index across analysis (best version: MD 0.20 (95%CrI 0.14-0.26), worst version: MD 0.18 (95%CrI 0.12-0.25), SUCRA 82.4). The Gupta Perioperative Risk for Myocardial Infarction or Cardiac Arrest score outperformed the Revised Cardiac Risk Index in the best version analysis (MD 0.16 (95%CrI 0.01-0.32)). Between-study heterogeneity was low. None of the included studies externally validated their machine learning models and only six were judged to be at low risk of bias. DISCUSSION: Most machine learning models showed better discrimination than traditional risk scores, with automated machine learning and gradient boosting models ranking highest. However, study quality, calibration reporting and absence of external validation limit immediate clinical adoption. Prospective, multicentre evaluation is required before integration of these models into peri-operative practice.

Humans↗

Risk Factors and Predictive Model for Postoperative High Myopia in Children Undergoing Congenital Cataract Surgery With Intraocular Lens Implantation.

PURPOSE: To identify risk factors associated with the development of high myopia following congenital cataract surgery and to establish a robust predictive model. DESIGN: Retrospective clinical cohort study. SUBJECTS: This retrospective study included 106 pediatric patients who underwent congenital cataract surgery with primary IOL implantation (mean follow-up 8.19 years). The model was externally validated in an independent cohort of 72 patients with a mean follow-up of 7.83 years. METHODS: Preoperative and postoperative ocular biometric parameters were collected. Risk factors for postoperative high myopia were analyzed using Cox proportional hazards regression, which served as the basis for model construction. The predictive performance of the model was rigorously evaluated for discrimination and calibration. Discriminative ability was quantified using Harrell's C-index and the area under the receiver operating characteristic curve (AUC). Model calibration was assessed via calibration plots by comparing predicted probabilities with actual observed outcomes. Internal validation was performed using a bootstrapping method (500 iterations) to ensure model stability and adjust for potential overfitting. RESULTS: An initial postoperative refraction of <+0.75D, and a higher IOL Power to Axial length Ratio (IOL/AL ratio) were identified as significant risk factors for the development of postoperative high myopia. Shorter preoperative axial length was associated with a greater magnitude of postoperative myopic shift. The predictive model demonstrated robust performance, achieving a C-index of 0.711 (internal validation C-index: 0.713). The area under the receiver operating characteristic curve (AUC) values for predicting high myopia at 5 and 10 years were 0.858 and 0.745, respectively. Furthermore, calibration curves demonstrated excellent agreement between the predicted and observed outcomes throughout the follow-up period. In external validation, the model achieved a C-index of 0.825, 5-year AUC of 0.833, and 10-year AUC of 0.713. CONCLUSIONS: Our analysis established that initial postoperative refraction <+0.75D, and an elevated IOL/AL ratio are key determinants of high myopia risk following surgery. Shorter preoperative axial length was associated with a greater magnitude of postoperative myopic shift. This predictive framework provides clinicians with a practical tool to optimize preoperative IOL selection and identify high-risk infants who require vigilant myopia prevention and balanced amblyopia management.

Humans↗

The Major Depression Rating Scale (MDS). Inter-rater reliability and validity across different settings in randomized moclobemide trials. Danish University Antidepressant Group.

The Major Depression Rating Scale (MDS) has been derived from the Hamilton Depression Scale and the Melancholia Scale. The MDS contains the nine DSM-IV items for major depression which all have anchoring scores from 0 to 4; hence, the theoretical score range is up to 36. The Major Depression Rating Scale has in this study been psychometrically analysed in randomized moclobemide trials. The results showed that the MDS had higher internal validity than the Hamilton Depression Scale. Thus, the homogeneity of the items was higher; factor analysis identified only one general depression factor (after 4 weeks of treatment explaining more than 50% of the variance). The inter-rater reliability of the two scales was of the same high level. The ability to measure changes (external validity) was tested in randomized clinical trials with moclobemide versus tricyclics (clomipramine and notriptyline) performed in Denmark in the psychiatric setting as well as in the general practice. The results showed that in the psychiatric setting tricyclics were superior to moclobemide with effect sizes ranging between 0.43 and 0.53. The highest effect size was obtained with the Melancholia Scale and the Major Depression Rating Scale, while the Hamilton Depression Scale was below 0.50. In the general practice setting no difference was found between moclobemide and clomipramine. In conclusion, the Major Depression Rating Scale has been found to have a more homogeneous factor structure than the Hamilton Depression Scale, but still with the same level of reliability and external validity. However, studies are needed to standardize the scale, especially in the general practice setting.

Antidepressive Agents↗

Transcriptome Analysis and Experimental Validation of Palmitoylation- Related Biomarkers in Atherosclerosis.

INTRODUCTION: Protein palmitoylation contributes to membrane localisation, signal transduction, and cell-fate regulation. It is closely associated with lipid metabolic dysfunction, immune inflammation, and vascular remodelling in atherosclerosis (AS). However, key palmitoylation-related transcriptomic markers and their potential causal associations with AS remain incompletely defined. METHODS: The Gene Expression Omnibus (GEO) dataset GSE100927 was used as the training cohort, and GSE43292 was used as an external validation cohort. Differentially expressed genes were identified using limma and intersected with palmitoylation-related genes to obtain palmitoylation-related differentially expressed genes (PRDEGs). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were then performed using clusterProfiler. Two-sample Mendelian randomisation was used to evaluate potential causal relationships between characteristic genes and AS. Feature selection was conducted using random forest and support vector machine recursive feature elimination (SVM-RFE), and the overlapping genes selected by both methods were retained. Receiver operating characteristic (ROC) curves were used to assess diagnostic performance. A five-gene nomogram was constructed, and its clinical utility was evaluated using calibration curves and decision curve analysis (DCA). Gene set variation analysis (GSVA) was applied to compare pathway activity between high- and low-expression groups for each core gene. Single-cell analysis using Seurat and expression-based cell-cell communication analysis using CellChat were conducted with GSE159677, and upstream transcription factors were predicted using NetworkAnalyst. For in vivo validation, an AS model was established in ApoE&#x2078;/&#x2078; mice fed a high-fat diet, and aortic gene and protein expression were assessed by RT-qPCR and western blotting. RESULTS: In GSE100927, 51 PRDEGs were identified. GO and KEGG enrichment analyses highlighted pathways associated with regulation of monoatomic ion transport, sarcomere and myofibril organisation, and immune inflammation. Mendelian randomisation suggested a potential protective causal association between SLC7A7 and AS. By integrating MR with random forest and SVM-RFE feature selection, we prioritised five core genes: PLCB2, GMIP, NEXN, PLN, and SLC7A7. These genes showed good diagnostic performance in GSE43292. The resulting nomogram was well calibrated and demonstrated stable net benefit in decision curve and clinical impact curve analyses. Single-gene GSVA identified consistently activated pathways across multiple genes, including innate and adaptive immune recognition, calcium signalling and myocardial contraction/cardiomyopathy, extracellular matrix-receptor interaction, cell junction pathways, autophagy-lysosome pathways, and several metabolic programmes. At the single-cell level, PLCB2 and GMIP were predominantly expressed in T cells and macrophages, NEXN and PLN were enriched in vascular smooth muscle cells, and SLC7A7 was mainly expressed in macrophages. CellChat analysis indicated increased signals for immune-related ligand-receptor interactions. In ApoE&#x2078;/&#x2078; mice fed a high-fat diet, PLCB2, GMIP, and SLC7A7 were upregulated, whereas NEXN and PLN were downregulated; protein-level changes were concordant with the transcriptomic trends. DISCUSSION: These findings indicate that palmitoylation-related dysregulation in AS converges on immune inflammation, calcium signalling/contractile programmes, ECM remodelling, and autophagy-linked metabolism. The five-gene panel is supported by external validation, single-cell localisation to immune and vascular compartments, and concordant results in ApoE&#x2078;/&#x2078; mice. CONCLUSION: This study identified and validated five palmitoylation-related genes associated with AS. SLC7A7 showed a potential protective causal signal in MR analysis. The enriched pathway patterns linked these genes to immune inflammation, calcium signalling-contraction coupling, ECM remodelling, cell adhesion, and autophagy- associated metabolic reprogramming. The five-gene nomogram showed potential utility for diagnostic classification and decision support, nominating candidate biomarkers and pathway targets for AS molecular subtyping, diagnosis, and mechanistic investigation.

Atherosclerosis (AS)↗

Standard cost lists for healthcare in Canada. Issues in validity and inter-provincial consolidation.

A standard cost list is a listing of recommended costs for a selected group of services. Standard costs are used in economic evaluation studies to eliminate that proportion of cost differences between interventions that are due to cost differences between providers. In this article we provide a summary of cost lists for pharmaceutical economic evaluation purposes which have been developed in 2 provinces in Canada-Alberta and Manitoba. We then assess these 2 lists from 2 different viewpoints. First, we developed criteria for the internal and external validity of costs and, in light of these validity criteria, we assessed how the 2 standard cost lists compared with the 'ideal' measure of long run marginal costs. Second, we identified the criteria for the inter-provincial consolidation of standard cost measures (in order to develop a single, consolidated cost list); in light of these criteria, we assessed whether the degree to which the 2 separate lists could be consolidated. The lists achieved a considerable degree of external validity, but fared less well in terms of internal validity. However, these results depend on the 'ideal' measure of cost which is used. The lists, in the forms which were developed, are not easily consolidated into a single list. Further refined cost data would be needed in order to achieve consolidation.

Alberta↗