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PubMed2001

Investigation of applicability of a mid-infrared spectroscopic method using an attenuated total reflection accessory and a new near-infrared transmission method for determination of faecal fat.

In many laboratories, the titrimetric method of Van de Kamer is used for the analysis of faecal fat content of patients suspected of steatorrhoea. We investigated the applicability of a mid-infrared (MIR) spectroscopic method, using an attenuated total reflection (ATR) accessory, and a new near-infrared (NIR) spectroscopic method. For the NIR method, sealed plastic bags containing the stool samples were used as transmission cells. Standardization was obtained using a previously described MIR method, with a NaCl flow-cell, as reference method. Partial least-squares regression was used for the calibration of each method. Full cross-validation of the calibration set was used for the internal validation of each method. Fifteen per cent of the stool samples could not be estimated with the ATR method within reasonable accuracy limits compared with the reference. The standard error of prediction of the NIR method was 1.1 g/dL. We conclude that the new NIR method is a promising technique for routine use. However, further experiments need to be done with triplicate measurements of each sample and the use of an external validation set.

Calibration↗

PubMed2026

Development and validation of a serum peptidomic signature for early detection of asymptomatic ovarian cancer: A multi-center prospective study.

Early detection of asymptomatic ovarian cancer (asym-OC) remains a critical challenge, the failure of which underlies its high mortality. Performing serum peptidomic profiling of 843 participants in the cohort SOCFCP, we distill 1,081 initial features into a 7-marker panel for asym-OC detection via a biology-informed machine-learning (ML)-based feature selection strategy. Three markers significantly revert toward non-OC levels after surgery. Integrating the panel with age, CA125, and HE4, we develop and externally validate (n = 159) a LightGBM model, ProMS+. For early-stage OC detection, ProMS+ shows a specificity of 92.6% at 95.0% sensitivity, outperforming CA125 (44.7%), HE4 (11.2%), and Risk of Ovarian Malignancy Algorithm (ROMA) (24.0%), with an area under the curve (AUC) of 0.993. In a simulated high-risk population (n = 100,000; OC prevalence = 1%), ProMS+ yields a high AUC (0.983) and a higher positive predictive value than CA125, HE4, and Age + CA125 + HE4 combined model (0.201 vs. 0.027, 0.090, and 0.064). ProMS+ offers a promising, non-invasive, and interpretable approach for the early detection of asym-OC.

Humans↗

PubMed2001

Functional rating index: a new valid and reliable instrument to measure the magnitude of clinical change in spinal conditions.

STUDY DESIGN: A prospective cohort design was used to evaluate the Functional Rating Index in a multicentered setting with 139 participants. The Functional Rating Index is a self-reporting instrument consisting of 10 items, each with 5 possible responses that express graduating degrees of disability. OBJECTIVES: The goal of this study was to evaluate the psychometric qualities of the Functional Rating Index. SUMMARY OF BACKGROUND DATA: The Functional Rating Index combines the concepts of the Oswestry Low Back Disability Questionnaire and the Neck Disability Index and seeks to improve on clinical utility (time required for administration). METHODS: One hundred thirty-nine subjects with spinal complaints participated in four different cohorts to study reliability, validity, responsiveness, and clinical utility. RESULTS: Reliability: Test-retest: Intraclass correlation coefficient was excellent (ICC3,k = 0.99); interitem correlation: Item efficiency was good, ranging between 0.54 and 0.82, with a moderate correlation among all items; Cronbach's alpha was excellent (0.92). VALIDITY: construct: The Functional Rating Index correlated with the Disability Rating Index (0.76), the Short Form-12 Physical Component Score (0.76), and the Short Form-12 Mental Component Score (0.36). Responsiveness: Overall, the size effect was 1.24, which is commendable. Clinical utility: Time required by the patient and staff averaged 78 seconds per administration, which is noteworthy. Effect of Sociodemographics: Total scores were not affected by education, gender, nor age, suggesting minimal external validity bias. CONCLUSIONS: The Functional Rating Index appears to be psychometrically sound with regard to reliability, validity, and responsiveness and is clearly superior to other instruments with regard to clinical utility. The Functional Rating Index is a promising useful instrument in the assessment of spinal conditions.

Adolescent↗

PubMed2026

Development and Validation of a Clinical Polygenic Risk Report in U.S.-Based Health Systems for 8 Cardiovascular Conditions.

BACKGROUND: Polygenic risk scores (PRS) stratify inherited cardiovascular risk, but their path to clinical implementation remains unclear. OBJECTIVES: We aimed to develop and validate integrated PRS for 8 cardiovascular conditions and outline a framework for their clinical reporting. METHODS: We analyzed genotype and clinical data from 245,394 All of Us Research Program participants. Publicly available PRS for 8 traits-coronary artery disease, atrial fibrillation, type 2 diabetes, venous thromboembolism (VTE), thoracic aortic aneurysm (TAA), extreme hypertension, severe hypercholesterolemia, and elevated lipoprotein(a)-were combined using PRSmix, an elastic-net approach. Integrated PRS were externally validated in 53,306 Mass General Brigham Biobank participants using logistic regression, adjusting for age, sex, and ancestry. RESULTS: Of 53,306 genotyped Mass General Brigham Biobank participants (55.6% women, mean age 53 ± 17 years), integrated PRS demonstrated robust discrimination and appropriate calibration across 8 cardiovascular traits. Comparing high genetic risk (top 10% of PRS distribution, or top 20% for rarer TAA and VTE) vs average risk (26th-75th percentiles, or 21st-80th percentiles for TAA and VTE) yielded ORs: coronary artery disease (3.7 [95% CI: 3.4-4.1]), type 2 diabetes (3.1 [95% CI: 2.8-3.3]), atrial fibrillation (3.0 [95% CI: 2.7-3.3]), VTE (1.9 [95% CI: 1.6-2.0]), TAA (1.7 [95% CI: 1.5-1.9]), hypertension (2.1 [95% CI: 1.8-2.3]), hypercholesterolemia (4.1 [95% CI: 3.7-4.5]), and lipoprotein(a) (41.0 [95% CI: 27.0-62.2]). Incorporating integrated PRS into clinical models improved risk classification, while prospective analyses confirmed significant associations with incident cardiovascular outcomes. CONCLUSIONS: Integrated PRS offer an implementable framework for genetic risk reporting, and are now available as a clinically orderable test. Broader prospective validation studies are needed to further establish clinical utility.

Humans↗

PubMed1994

Multidimensional health locus of control beliefs and psychological health for a sample of mothers.

Five multidimensional health locus of control (MHLC) types for 772 women whose children are enrolled in a longitudinal study of their health and development were identified. The MHLC is composed of an internal and two external dimensions (chance and powerful others). The five independent MHLC clusters were: pure internal; believer in control; pure chance; yea-sayer; and nay-sayer. Women with high scores on the three dimensions of the MHLC (yea-sayer) compared with the rest of the sample were significantly more likely to be from a lower socio-economic status, score lower on a general verbal intelligence test and higher on the Neuroticism and Lie Scales of the Eysenck Personality Inventory. They rated their overall health as significantly poorer, and reported more symptoms of depression compared with the other groups. A pure internal locus of control was strongly associated with the report of good health. Women with a strong belief in internal and powerful other loci of control were significantly more likely to have received treatment for their depression compared with other groups. Help-seeking for children's problem behaviour did not vary significantly with MHLC groups. The present study replicated five out of six MHLC types identified in an earlier study, and established the external validity of the MHLC types on measures of health status. The findings support the use of MHLC types in future research on health locus of control.

Adolescent↗

PubMed1998

The Children of Alcoholics Screening Test (CAST): test-retest reliability and concordance validity.

The stability of the Children of Alcoholics Screening Test (CAST) has been called into question by several authors (Hart, 1989; Maxwell, 1985; Schinke, 1989; Stacey 1985). In a bid to verify these reservations, 376 college students were each evaluated twice by means of the CAST. Results confirm the high reliability and validity of this instrument in identifying grown-up children raised in homes with at least one alcoholic parent. Reliability was demonstrated by good internal consistency, high item-total scale correlations, and near perfect test-retest agreement (k = .83). Furthermore, concordance between high CAST scores and satisfaction of recognized criteria for alcohol dependence, as measured with the Structured Clinical Interview for the DSM-III-R (SCID), attests to the CAST's external validity (k = .78). Moreover, factor analysis shows the instrument to have a unidimensional structure. Finally, with a cutoff score of 6 or more, the CAST demonstrates excellent sensitivity and specificity.

Adult↗

PubMed1994

Substance use clusters in a college sample: a multitheoretical approach.

Substance use factors were examined and cross-validated in a cluster analytic approach in two independent samples of college students: N = 291 and N = 602. Reported frequency, intensity, and amount of substance use were examined for beer, hard liquor, marijuana, amphetamines, barbiturates, psychedelics, cocaine, and heroin. Variables were reduced using Principal Components Analysis (PCA) to form four substance use composites. Composite scores were entered into two different methods of cluster analysis that each identified four distinct clusters of substance use groups. External validity was obtained by showing that these four groups differed on a set of relevant variables. The four groups served as levels of the independent variable, substance use type, in four MANOVAs examining group differences on peer and family influence, psychosocial functioning, habit acquisition, and self-efficacy. Findings indicate that as frequency and intensity of substance use increased, individuals reported more problems in living, although a causal direction cannot be established. The findings are of potential value in early identification, prevention, and education regarding substance use among college populations.

Adaptation, Psychological↗

PubMed2005

Postoperative nomogram predicting the 10-year probability of prostate cancer recurrence after radical prostatectomy.

PURPOSE: A postoperative nomogram for prostate cancer recurrence after radical prostatectomy (RP) has been independently validated as accurate and discriminating. We have updated the nomogram by extending the predictions to 10 years after RP and have enabled the nomogram predictions to be adjusted for the disease-free interval that a patient has maintained after RP. METHODS: Cox regression analysis was used to model the clinical information for 1,881 patients who underwent RP for clinically-localized prostate cancer by two high-volume surgeons. The model was externally validated separately on two independent cohorts of 1,782 patients and 1,357 patients, respectively. Disease progression was defined as a rising prostate-specific antigen (PSA) level, clinical progression, radiotherapy more than 12 months postoperatively, or initiation of systemic therapy. RESULTS: The 10-year progression-free probability for the modeling set was 79% (95% CI, 75% to 82%). Significant variables in the multivariable model included PSA (P = .002), primary (P < .0001) and secondary Gleason grade (P = .0006), extracapsular extension (P < .0001), positive surgical margins (P = .028), seminal vesicle invasion (P < .0001), lymph node involvement (P = .030), treatment year (P = .008), and adjuvant radiotherapy (P = .046). The concordance index of the nomogram when applied to the independent validation sets was 0.81 and 0.79. CONCLUSION: We have developed and validated as a robust predictive model an enhanced postoperative nomogram for prostate cancer recurrence after RP. Unique to predictive models, the nomogram predictions can be adjusted for the disease-free interval that a patient has achieved after RP.

Adult↗

PubMed2005

Development of a foot impact scale for rheumatoid arthritis.

OBJECTIVE: To develop a new foot impact scale to assess foot status in rheumatoid arthritis (RA) using established qualitative methodology and the latest item response techniques (Rasch analysis). METHODS: Foot problems in RA were explored by conducting qualitative interviews that were then used to generate items for a new foot impact scale. Further validation was undertaken following postal surveys and Rasch analysis. RESULTS: Analysis of the first postal survey (n = 192 responses) produced a 63-item binary response, 4-subscale instrument. The 4 subscales covered the domains impairment, activities, participation, and footwear. Following test-retest postal surveys and additional analysis, the instrument was reduced to a 2 subscale, 51-item questionnaire covering the domains of impairments/shoes and activities/participation. Initial results of these subscales indicate good psychometric properties, external validity, and test-retest reliability. CONCLUSION: A foot impact scale to assess the impact of RA and to measure the effect of interventions has been developed. The 2 scales comprising the instrument demonstrate good psychometric properties.

Adult↗

PubMed1997

[Conners' rating scales in the assessment of attention deficit disorder with hyperactivity (ADHD). A new validation and factor analysis in Spanish children].

The use of Conner's Rating Scales (CRS) is very extended for the assessment of attention deficit disorder with hyperactivity (ADD-H). The main objective of this work is to study the validity of construct of CRS from theoretical basis and data statistical analysis. The study is based on a control group of 633 children and a clinical group of 33 subjects. We used a Spanish version of the Conner's Teacher Rating Scale (CTRS) and Conner's Parents Rating Scale (CPRS) in both groups. From the analysis of scales contents we attribute the items to several behavioral areas and we performed a factorial analysis. Studies of reliability, external validity versus clinical criteria, and analysis of correlations between parents and teachers scales were also performed. Findings from factorial analysis and study of reliability have shown the questions of CTRS to be clustered in three well-defined and reliable factors: hyperactivity, attention deficit, and conduct disorder. The questions dealing with emotional disorders are not sufficiently consistent to constitute a separate factor. CPRS has a lower reliability than CTRS, and its factorial analysis does not allow to consider a factorial distribution. The validity is high in CTRS and no significative in CPRS. Correlation between scales is also low. As a consequence of these results we propose a Spanish experimental revised form of the CTRS, with 20 items. This new form can assess separately: attention deficit; hyperactivity and conduct disorder, according to the current clinical criteria of CIE-10 and DSM-IV.

Attention Deficit Disorder with Hyperactivity↗

PubMed1993

Validation of sentinel data.

The Dutch Sentinel Practice Network, "de Peilstations" started in 1970. The purpose of this network is to gain a better insight into the epidemiology of a number of illnesses and conditions as they are presented to the general practitioner. The network is sponsored by the Ministry of Welfare, Public Health and Culture. Value was attached to the distribution of the spotter physicians over the country and by degree of urbanisation. The presence of 1% of the population of the four provinces groups and the three urbanisation groups has been observed in the practices of the spotter physicians. The completeness of the registration, the internal and the external validity of the data collected by the physicians are discussed.

Adolescent↗

PubMedDate not supplied

Decisional balance and stage of change for adolescent drinking.

The Transtheoretical Model of Change has been proven very effective in explaining both the acquisition and cessation of many health related behaviors. In this study, this model was applied to the domain of immoderate alcohol use among adolescents (usually drinking three or more drinks per occasion). Measures for two constructs of the model were developed: Stage of Change and Decisional Balance. A total of 853 tenth and eleventh graders who attend vocational training programs were administered a 37-item decisional balance questionnaire and a 5-item staging measure. A short (16-item) psychometrically sound Decisional Balance Inventory was developed based on an exploratory factor analysis that identified two factors, the Pros and Cons of Alcohol Use. The factor structure was confirmed using structural modeling techniques on a hold-out sample. Based on a combination of model fit and parsimony considerations, an uncorrelated model was selected (IFI2 = .909). Students were classified into one of nine stages of acquisition or cessation. External validity was established by the significant and meaningful differences between the stages of change on the pros and cons of alcohol use. Implications of this research are discussed.

Adolescent↗

PubMed2006

Demand-oriented care: the development and validation of a measuring instrument.

OBJECTIVES: Demand-oriented care has recently become a key topic in the area of care provision, fitting into the modern pursuit for patient autonomy. This paper introduces a measuring instrument to assess demand-orientation in mental health care. METHOD: A concept mapping procedure was used to understand the concept of demand-orientation. The resulting items were introduced to a validating sample of 204 patients of three mental health facilities. After factor analysis, a 19-item General-Demand Orientated Care Questionnaire (DOC-G), and a supplementary questionnaire (DOC-S) containing 6 sections remained. This questionnaire was submitted to confirmatory analysis in a random sample (n = 304) of psychiatric patients. RESULTS: Respondents were predominantly female (57.6%), of Dutch ethnic origin (84.1%), and outpatients (71.4%). The analyses confirmed the 4-factor structure of the questionnaire. Both internal and external validity of the instrument proved to be sufficient. The questionnaire discriminated in the experience of demand-orientation of care between patients who did and those who did not have a treatment plan put up; between those who did and those who did not have a crisis plan, and between those who had a lifetime prevalence of undergoing compulsory treatment, and those who had not. CONCLUSIONS: We conclude that the DOC is a useful instrument to measure demand-orientation in a population of psychiatric patients. It is useful to measure changes in care quality. The supplementary questionnaires make it possible to evaluate chosen projects or subprojects quickly.

Adult↗

PubMed1980

Caution and conservatism in the use of a psychiatric day hospital: evidence from a research project that failed.

A randomized trial to evaluate day hospital care as an alternative to inpatient treatment in the acute phase of psychiatric illness was abandoned when too few patients were admitted to the trial to enable any valid generalization to be made concerning the total at-risk population. In accounting for the failure of the experimental design, attention is drawn to the inability of the research team to influence either the organization of the unit, whereby junior staff had no contact with the day hospital, or the prevailing belief among senior staff that the two treatment settings serve distinctive, not alternative, functions. The implications of our failure for the feasibility of conducting a successful and externally valid controlled trial in this research setting are explored.

Clinical Trials as Topic↗

PubMed1996

Blood pressure measurements in epidemiological surveys--time to change?

Blood pressure recordings in epidemiological surveys are usually obtained by non-ambulatory, multiple one-occasion, manual sphygmomanometric measurements by trained observers in study participants subjected to standardized examination conditions. High validity and reliability of blood pressure measurements ensure the comparability of study results obtained in different places and at different times, and have a major impact on the detection of correlates and determinants of blood pressure and hypertension. A blood pressure measurement quality assessment was performed within the multi-center collaborative WHO-MONICA Project investigating results of 47 surveys from various geographic regions of the world. In an overall summary assessment, six out of these 47 surveys were found to have had major measurement problems which prohibited their further inclusion in collaborative analyses. Most of the problems were associated with observer-related factors. Therefore, it was contended that automatic blood pressure measurement devices might be able to reduce and abolish most of these "nuisance" factors. In 1995, we had the opportunity to simultaneously study two independent random samples of men and women, aged 45 to 64 years, from the city of Augsburg in Southern Germany. One sample was examined by 16 observers with a random zero sphygmomanometer (MONICA Augsburg), the other sample (J.A.P. Study) was examined by two observers with an invasively validated, automatic oscillometric device (boso Oscillomat). In both surveys, blood pressure was measured three times under similarly standardized conditions. comparing the blood pressure results of the two surveys, the intra-individual measurement variation tended to be slightly higher with the Oscillomat than the random zero, and the population mean blood pressures and hypertension prevalences were found to be significantly lower with the Oscillomat. We conclude that manual measurements of blood pressure by sphygmomanometer should not be indiscriminately replaced externally validated automatic devices. The imponderabilities of automatic devices with varying technical principles have to be assessed in epidemiological settings weighed against recognized disadvantages of sphygmomanometry before any recommendations can be given as to changing the present epidemiological practice.

Bias↗

PubMed2026

A validated, modifiable proteomic score from the EXSCEL trial predicts cardiovascular events in diabetes.

BACKGROUNDAdults with type 2 diabetes mellitus (T2DM) are at increased risk for stroke, myocardial infarction, and cardiovascular death, yet individual risk is heterogeneous and incompletely captured by clinical models.METHODSIn the Exenatide Study of Cardiovascular Event Lowering (EXSCEL), adults with T2DM were randomized to a GLP-1 RA (exenatide) or a placebo and followed longitudinally for major adverse cardiovascular events (MACE). High-throughput discovery proteomics was done in plasma collected at baseline and 12 months. Proteins associated with time to MACE were identified using multivariable regression and incorporated into supervised machine learning models. A multi-protein score was developed and externally validated in 2 independent population-based and trial cohorts.RESULTSThe proteomic score showed incremental improvement in cardiovascular risk discrimination beyond clinical factors alone, and several proteins were consistently prioritized across modeling approaches. The protein score and a top-ranked protein, tetranectin, were modified by GLP-1 RA treatment, and a decrease in protein score was associated with improved outcomes, supporting modifiability of MACE risk.CONCLUSIONExternal validation confirmed generalizability across cohorts with and without diabetes. Together, these findings demonstrate that plasma proteomic signatures can enhance cardiovascular risk stratification and identify treatment-responsive biomarkers in T2DM, supporting their potential role in precision prevention strategiesFUNDINGThe EXSCEL study was funded by Amylin Pharmaceuticals. This research was supported by contracts HHSN268201200036C, HHSN268200800007C, HHSN268201800001C, N01HC55222, N01HC85079, N01HC85080, N01HC85081, N01HC85082, N01HC85083, N01HC85086, 75N92021D00006, and grants R01HL146145, U01HL080295, U01HL130114, R01HL172803, and R01HL144483 from the National Heart, Lung, and Blood Institute, with additional contribution from the National Institute of Neurological Disorders and Stroke. Additional support was provided by R01AG023629 from the National Institute on Aging.

Aged↗

PubMed2026

Transcriptomic profiling across stages of non-muscle-invasive bladder cancer identifies fibroblast activation protein-alpha as a stromal biomarker associated with progression.

BACKGROUND: T1 non-muscle-invasive bladder cancer (NMIBC) represents a biologically aggressive subgroup with substantial heterogeneity in recurrence and progression risk. Current clinicopathological risk stratification tools lack sufficient precision to identify patients at the highest risk of progression to muscle-invasive bladder cancer (MIBC). OBJECTIVE: To characterize transcriptomic differences between T1 and < T1 (Ta/Tis) NMIBC and to explore the association of fibroblast activation protein-α (FAP) gene expression with disease progression. METHODS: Transcriptomic profiling was performed on formalin-fixed paraffin-embedded (FFPE) tumor tissue from 66 patients with primary, treatment-naïve NMIBC and 5 patients with T2 disease (included for exploratory comparisons). Analyses included differential gene expression, gene set enrichment analysis (GSEA), molecular subtyping, immune cell deconvolution, and evaluation of FAP expression in relation to recurrence and progression. External validation of FAP was conducted in three independent NMIBC cohorts. RESULTS: T1 tumors demonstrated a distinct transcriptomic profile compared with < T1 tumors, characterized by enrichment of cell cycle-related and metabolic pathways and a higher prevalence of aggressive molecular subtypes. Despite these molecular differences, no statistically significant differences in recurrence-free, progression-free, cancer-specific, and overall survival were observed, likely reflecting limited event numbers. Among recurrent tumors, early recurrences (≤ 24 months) were associated with epithelial-mesenchymal transition signatures. FAP expression increased with tumor stage (p = 0.0005) and was associated with progression (p = 0.002) and mortality (p = 0.01). Patients with tumors in the highest quartile of FAP expression had worse progression-free survival. This association was consistently observed in three external NMIBC cohorts. CONCLUSIONS: T1 NMIBC exhibits distinct transcriptomic features suggestive of increased biological aggressiveness. Elevated FAP expression is reproducibly associated with progression risk across multiple cohorts, supporting its potential role as a biomarker of aggressive disease. Given the limited number of progression events, these findings should be considered hypothesis-generating and warrant prospective validation before clinical implementation.

Humans↗

PubMed2001

Monitoring improvement using a patient-rated depression scale during treatment with anti-depressants in general practice. A validation study on the Goldberg Depression Scale.

OBJECTIVE: To perform a pilot study on the value of the Goldberg Depression Scale as an instrument for monitoring improvement in depressed patients treated with anti-depressants in general practice. DESIGN: A comparative study using simultaneous ratings on the observer-based 17-item Hamilton Depression Scale and the patient-rated Goldberg Depression Scale. SETTING: General practice. PATIENTS: Twenty-one patients meeting the ICD-10 criteria of a moderate depressive episode were assessed at the time of inclusion and through three follow-up visits. MAIN OUTCOME MEASURES: Scores on the Goldberg Depression Scale compared to the Hamilton Depression Scale. RESULTS: An acceptable internal and external validity of the Goldberg Depression Scale was demonstrated. The Loevinger coefficient varied from 0.25 at the time of diagnosis to 0.57, 0.65 and 0.69 by visits two, three and four. Factor analysis identified only one general factor explaining 50% or more of the variants, except at visit 1. When the Goldberg Depression Scale was correlated to the Hamilton Depression Scales, a coefficient of 0.74 was obtained (p < 0.001). CONCLUSION: This pilot study indicates that the Goldberg Depression Scale is suitable for monitoring improvement in depressed patients treated in general practice. Further studies are recommended.

Antidepressive Agents↗