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Results for “validation study”

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At least 127 records · Page 7Linked to original sources

PubMed1987

Dietary intake of individuals interested in eating a healthy diet: a validated study of intake before and after dietary advice.

The food intake of 37 adult volunteers (12 M, 25 F) interested in eating a healthy diet was measured on two occasions by the 7-day weighed record method. In week 1 subjects consumed their habitual diet and in week 2 attempted to follow dietary recommendations (DR). Intakes were compared with recommended dietary allowances (RDA) and with dietary guidelines (DG). Validation of recorded energy intakes against changes in body weight, and sodium, potassium and nitrogen intakes against urine excretions suggested reliable dietary records in both study weeks. Mean dietary intakes in week 1 met the RDA for all nutrients studied except for energy (which was close) and zinc (in females only). Daily energy intake was 2160 kcal (9.04 MJ) in week 1 and 1810 kcal (7.56 MJ) in week 2, and subjects lost weight during week 2. Absolute intakes of vitamins and minerals were similar in both study weeks, thus increasing nutrient density in week 2 and suggesting improved dietary quality. Mean dietary intakes in week 1 conformed more closely to DG than commonly reported and changed in the direction recommended in week 2. Mean daily intakes in week 1 and week 2 respectively were: fibre, 31 and 34 g; sodium 114 and 90 mmol; Na:K ratio, 1.37 and 1.10; alcohol, 3.3 and 2.3 per cent of total energy; fat, 38.7 and 34.2 per cent of food energy or 37.4 and 33.4 per cent of total energy. Intake of fibre increased with respect to energy but sodium intake per unit energy did not decrease. Energy intake was positively related to sodium, fibre and zinc intakes and influenced ease of conformity to DR for these nutrients. It is concluded that our motivated subjects were able to make short-term dietary changes consistent with DR. Whether or not these changes continue in the long term is the subject of a follow-up study.

Adult↗

PubMed1977

A validational study of the WIST as a group-administered instrument for assessment of schizophrenic thinking.

The objective assessment of thought disorder in schizophrenia is problemmatic in clinical psychology. Recently an individually administered instrument (WIST) was introduced as a brief, objective, and quantitative measure of schizophrenic thought processes. Possible shortcomings of the WIST are noted; experimental findings that concern extension to group testing conditions, convergent validity with another self-report measure of schizophrenia, and discriminant validity from intellectual level are presented.

Adult↗

PubMed1991

Non-invasive Doppler-derived cardiac output: a validation study comparing this technique with thermodilution and Fick methods.

The high mortality and morbidity related to cardiac events remains a considerable problem in vascular surgery. Predicting high risk patients is difficult except perhaps by coronary angiography which is invasive, costly and impractical. It would be useful to have a technique which could easily measure cardiac output and stratify cardiac risk in patients needing vascular surgery. Doppler-derived cardiac output may be such a technique. It offers considerable advantages over Swan-Ganz thermodilution measurement in that it is non-invasive, continuous, inexpensive, and requires only limited technical skill and training. In order to assess and validate a Doppler cardiac output monitor (ACCUCOM 2, Datascope Medical Co. Ltd.), we undertook a prospective study comparing Doppler-derived measurements with those obtained by thermodilution and Fick methods. Twelve patients undergoing elective coronary angiography were studied. Swan-Ganz thermodilution catheters were inserted on completion of cardiac catheterisation and five consecutive thermodilution and Doppler measurements made in each patient. Oxygen saturation from pulmonary artery and aortic blood samples, and a single indirect Fick cardiac output, were calculated. Linear regression analysis for Doppler against thermodilution gave a correlation co-efficient (r) of 0.81 (p less than 0.002), and (r) for Doppler against the Fick method was 0.76 (p less than 0.02). Bland and Altman's statistical method showed the differences to be normally distributed. The mean difference (thermodilution minus Doppler) was 0.32 l/min SD 0.48 l/min, 95% confidence limits -0.64 to +1.28 l/min. Doppler-derived cardiac output compares well with traditional methods of measurement and may be a useful tool in the assessment and monitoring of the high risk vascular patient.

Adult↗

PubMed1991

Social factors and minor psychiatric disorder in middle-aged men: a validation study and a population survey.

A cross-sectional survey of minor psychiatric disorder is reported in a representative community sample of 2204 men between the ages of 45 years and 64 years living in Caerphilly, South Wales. Minor psychiatric disorder was measured by the 30-item General Health Questionnaire and validated by the Clinical Interview Schedule in a consecutive sample of 97 men, weighted to provide one-third cases, two-thirds non-cases. A case threshold of 4/5 on the General Health Questionnaire was chosen on the basis of 'ROC' analysis. An overall estimated 'true' prevalence rate for minor psychiatric disorder of 22.0% was found, with 22.3% of men scoring 5 or more on the General Health Questionnaire. Rates of minor psychiatric disorder were higher in widowed and divorced men than in married men but were also, unexpectedly, lower in single as opposed to married men. There was no social-class gradient in minor psychiatric morbidity but a lower rate in Social Class III NM may be largely explained by lower unemployment rates. There were markedly higher rates of minor psychiatric morbidity in unemployed men and those who retired ill. Men with no available social contacts had higher rates of morbidity than men with some or high social contacts.

Cross-Sectional Studies↗

PubMed1986

Upper extremity function in hemiplegia. A cross-validation study of two assessment methods.

The methods devised by DeSouza et al. and by Fugl-Meyer et al. for description of upper extremity function after stroke were compared by parallel assessments in a consecutive series of 50 patients with hemimotor deficit. Very close positive associations between both methods indicated a high degree of cross-validity. As both methods appear to be externally valid, have good inter-rater reliability and as the time needed for assessing the arm function of a hemiplegic or hemiparetic patient rarely exceeds 10 min, it appears that the two methods possess about equal descriptive power.

Arm↗

PubMed1985

Validation study of the New York State Optometric Association (NYSOA) Vision Screening Battery.

The New York State Optometric Association (NYSOA) Vision Screening Battery was administered to 1983 grade school children. Complete visual examinations were performed on 125 children. A consensus method for determining a diagnosis was developed and a double-blind paradigm was used to validate the screening battery. The sensitivity was found to be 71.7% and the specificity to be 65%. When compared to the Snellen test, the NYSOA battery is far more sensitive. The Snellen test is 100% specific but misses 75.5% of the children found to have vision problems when given a complete visual examination.

Child↗

PubMed2026

An individualized nomogram for predicting progression-free survival in systemic anaplastic large cell lymphoma: a multicenter, retrospective, and internally validated study.

OBJECTIVES: To develop an individualized nomogram for predicting disease progression risk in systemic anaplastic large cell lymphoma (sALCL). METHODS: Independent predictors of progression-free survival (PFS) were identified using Cox regression in a multicenter retrospective cohort of 109 sALCL patients (2010-2022). These were incorporated into a three-factor nomogram, evaluated via bootstrapped internal validation (1000 resamples), ROC analysis, C-index, decision curve analysis (DCA), and clinical impact curve (CIC). RESULTS: A total of 29 PFS events occurred during a median follow-up of 31 months. Multivariable modelling selected serum β2-microglobulin elevation, extranodal disease, and front-line chemotherapy choice (CHOP versus CHOPE or BV+CHP) as autonomous progression drivers. Upon internal bootstrap validation, the nomogram yielded strong prognostic accuracy, achieving AUCs of 0.81, 0.85 and 0.87 for 1-, 3- and 5-year progression-free survival, alongside a corrected C-index of 0.779 (95% CI: 0.699 - 0.861). Calibration plots showed close agreement between predicted and observed outcomes, while DCA confirmed superior net clinical benefit versus conventional IPI or Ann Arbor stratification across multiple decision thresholds. CONCLUSION: This first sALCL-specific nomogram integrates clinical and treatment variables to provide personalized PFS risk estimation. While internally validated, this exploratory, observation-based tool requires external validation and recalibration in prospective cohorts before clinical implementation.

Humans↗

PubMed1977

The measurement of obsessionality: first validation studies of the Lynfield obsessional/compulsive questionnaires.

The difficulties encountered in attempts at the rating and quantification of obsessional behaviour are outlined and some of the reasons for such difficulties are mentioned. The development of the Lynfield Obsessional-Compulsive Questionnaire from the Leyton Obsessional Inventory is discussed together with the advantages and disadvantages attendant upon its administration. The author concludes that the Lynfield Obsessional-Compulsive Questionnaire promises well as a measure for assessing change and that, following further validity and reliability tests, it may be used in multicentre trials of treatment procedures.

Evaluation Studies as Topic↗

PubMed1984

Measuring family functioning with the MMPI: a reliability and concurrent validity study of three MMPI family scales.

Examined the utility of three MMPI family scales. Three MMPI family scales and three criterion family scales were administered to 110 undergraduates. Internal consistency coefficients were calculated for each MMPI family scale. Relationships between the MMPI family scales and the criterion scales are examined by a correlational analysis. Findings suggest that the MMPI family scales are reliable and concurrently valid measures of an individual's perception of interpersonal family relationships. Procedures for scoring and interpreting the MMPI family scales are examined. The findings also indicate which MMPI family scale is the overall best scale.

Adolescent↗

PubMed1990

Mean transit time for videodensitometric assessment of myocardial perfusion and the concept of maximal flow ratio: a validation study in the intact dog and a pilot study in man.

Over the last decade it has become more and more obvious that besides anatomical information about the severity of coronary artery stenoses, information about coronary and myocardial blood flow is necessary to understand the functional significance of these obstructions and to evaluate the result of an intervention. Several methods have been proposed for this purpose, each of these having their particular limitations. In this study a new method is shortly described which allows the accurate calculation of relative maximal myocardial perfusion by ECG-triggered digital radiography (videodensitometry), using mean transit time (Tmn) as time parameter; this technique is based on the original physiologic principles of indicator dilution theory. This method was validated in 8 instrumented dogs in which an excellent linear relation was present between 1/Tmn and flow (r = 0.96 +/- 0.03). Although this method does not allow assessment of resting flow and therefore coronary flow reserve (CFR), it provides a means for the reliable comparison of maximal myocardial flow in different situations and it is independent of most factors affecting coronary flow reserve. The ratio between maximal flow after and before an intervention is called maximal flow ratio (MFR) and this concept was applied in a pilot study in man to evaluate PTCA results in 10 patients undergoing elective angioplasty. MFR was compared with the result of exercise testing 24 hours before and 10 days after the angioplasty. MFR greater than or equal to 1.5 was always accompanied by reversal of exercise test result from positive to negative. We conclude that the accurate calculation of relative maximal perfusion of the myocardium is possible by videodensitometry and suggest that comparison of maximal flow after and before an intervention can be valuable in man for functional evaluation of the result of the intervention.

Adult↗

PubMed1992

The Hamilton scales and the Hopkins Symptom Checklist (SCL-90). A cross-national validity study in patients with panic disorders.

The HRSD, HRSA, SCL-90 scales were psychometrically investigated in a cross-national sample of patients with varieties of non-psychotic symptoms of anxiety and depression. Across the cultural backgrounds the scores obtained from the original versions of these scales are not sufficient statistics. However, latent structure analysis has identified homogeneous subscales for depression (the HRSD) and for discomfort (an SCL subscale). High concurrent validity was found between the subscales of depression, anxiety and discomfort. In international research, inhomogeneity among scale items can be confounded with group differences which are usually ascribed to drug differences.

Adult↗

PubMed1987

Measurement of regional myocardial perfusion and mass by subselective hydrogen infusion and washout techniques: a validation study.

A technique was developed for measuring regional myocardial perfusion by intracoronary infusions of hydrogen (H2)-saturated saline. H2 concentration was detected during washout in the pulmonary artery by means of the voltage response of a platinum-tipped electrode. Regional myocardial perfusion was calculated from the H2 exponential desaturation curve according to the Kety-Schmidt principle. In 16 anesthetized open-chest dogs, validation of this technique was performed at baseline, reduced (stenosis), and hyperemic (dipyridamole) flow states by means of the radionuclide-labeled microsphere reference withdrawal technique. There was an excellent quadratic correlation between microsphere and H2 washout techniques (range 0.11 to 3.15 ml/min/g) (n = 33, r = .92, y = -0.12x2 + 0.89x + 0.20, SEE = 0.20 ml/min/g; p less than .0001). Hyperemic regional myocardial perfusion was underestimated by H2 washout and severely ischemic regional myocardial perfusion was overestimated. When regional myocardial perfusion values greater than twice normal were excluded, a strong linear correlation was present between H2 and microsphere measurements (n = 27, r = .89, y = 0.76x + 0.22, SEE = 0.18 ml/min/g; p less than .0001). The H2 washout method was further tested in 18 additional open chest dogs for calculations of the mass of an arterial perfusion bed according to the principle that the mass of the bed (g) equals coronary blood flow (ml/min) divided by regional myocardial perfusion (ml/min/g).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1988

[Validation study of the Mannheim Peritonitis Index].

113 patients suffering from purulent peritonitis entered this retrospective study for evaluation of the prognostic value of the Mannheim Peritonitis-Index. There was no lethality below an index x = 21, between x = 21 and x = 29, it was 29% and lethality increased to 100% in patients with an index x greater than or equal to 30. Statistical validation showed that prognosis was correct in 93% for the index x = 27, with a sensitivity and specificity of also 93%. Between x = 21 and x = 29 prognosis of the MPI was correct in at least 65%. The MPI is shown as a prognostic index for peritonitis with high accuracy in individual prognosis, that could be easy routinely documented.

Adolescent↗

PubMed1977

Dream reports and the test of emotional styles: a convergent - discriminant validity study.

Thirty-eight undergraduates completed the forced-choice form of the Test of Emotional Styles and participated in a 4-day dream recall study. Correlational analysis was performed with the three dimensions of emotional style and two dream report aspects as variables. The dimensions failed to correlate significantly with any of the dream report variables, although the dimensions intercorrelated significantly among themselves. Doubt is expressed as to the construct validity of the subscales of the Test of Emotional Styles.

Affect↗

PubMed2026

PCSK9 as a Key Gene of Metastasis in Lung Adenocarcinoma: A Multi-omics and Experimental Validation Study.

BACKGROUND: Lung adenocarcinoma (LUAD) is the most common form of lung cancer. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is abnormally expressed in various tumor tissues and is associated with malignant phenotypes. However, the clinical significance, function, and mechanism of LUAD invasion and metastasis remain unclear. METHODS: We retrospectively enrolled 100 patients with LUAD in this study. Initially, qRT-PCR was performed to detect PCSK9 levels in clinical tissues. Subsequently, bioinformatics analysis of scRNA-seq and The Cancer Genome Atlas Program (TCGA) datasets was performed to predict the role of PCSK9 in tumor cell malignancy and its potential downstream pathways. These predictions were validated experimentally using the CCK-8 assay, TUNEL staining, wound healing, transwell invasion assay, and an in vivo lung metastasis model. Finally, Western blotting and an AKT inhibitor (MK2206) were used to verify the underlying mechanism. RESULTS: PCSK9 was significantly upregulated in LUAD tissues compared to paracancerous tissues and was associated with poorer OS and DFS. Bioinformatics analysis of scRNA-seq data and TCGA analysis predicted that PCSK9 is highly enriched in tumor cells and is involved in EMT, and that the PI3K/AKT pathway plays a significant role in LUAD development. Experiments confirmed that PCSK9 markedly promoted LUAD cell proliferation, migration, and invasion in vitro and lung metastasis in vivo. PCSK9 overexpression significantly upregulated p-AKT, p-PI3K, and p-mTOR levels. Furthermore, the AKT inhibitor, MK2206, reversed the promoting effects of PCSK9. CONCLUSIONS: PCSK9 expression is associated with the prognosis and diagnosis of LUAD. This molecule activates the PI3K/AKT signaling pathway, thereby driving invasion, metastasis, and proliferation in LUAD.

Humans↗

PubMed1988

Multicenter validation study of real-time ultrasonography, arteriography, and pathology: pathologic evaluation of carotid endarterectomy specimens.

The morphologic description and measurements of endarterectomy specimens are usually believed to be accurate and are used as the gold standard against which the findings of diagnostic procedures are judged. Pathology data on 289 endarterectomy specimens from five participating centers and the corresponding angiography and B-mode ultrasonography data provided a basis for scrutinizing the validity of using the morphologic measurements as a standard. Discrepancies of greater than 1 mm between pathology and angiography measurements of minimum residual lumen occurred in 35% of the cases and between pathology and B-mode ultrasonography measurements in 64% of the cases. Discrepancies of greater than 1 mm between pathology- and angiography-measured lesion width occurred in 81% of the cases and between pathology and B-mode ultrasonography measurements in 64% of the cases. The cases representing mismatches of greater than 1 mm at one participating center were subjected to a rigorous review, with remeasurement of all morphologic features, in an attempt to explain the discrepancies. Various types of artifactual distortion of the specimens, the presence of slit-like and occluded lumens that were likely related to loss of perfusion pressure, and an inability to match planes of interrogation used in angiography and B-mode ultrasonography with pathology planes contributed significantly to the existence of mismatches. On the other hand, fixation and decalcification produced minimal and insignificant distortional changes. We conclude that the acquisition of quantitative data from endarterectomy specimens and the acceptance of morphologic data as a standard are limited by a number of problems that can be defined but have been difficult to resolve.

Carotid Arteries↗

PubMed1988

Screening for depressive symptoms among the elderly in Israel. A reliability and validity study.

The Hadassah Elderly Depression Screening Scale (HEDSS)--a modified version of Zung's Self-Rating Depression Scale and Beck's Depression Index--was developed for use among the elderly in Israel. In a sample of 183 elderly residents of Jerusalem, the scale proved to be highly reliable and able to differentiate between persons diagnosed as depressed and those defined as healthy. Moreover, it was found to be valid among subpopulations grouped by sex, education and ethnicity. Various cutoff points were tested for targeting screening at specific populations.

Aged↗

PubMed1989

Quality of the home environment of toddlers: a validation study of the home inventory.

The Home Observation for Measurement of the Environment (HOME) Inventory is introduced in this study to examine the home environments of children (three to four and a half years) in Singapore. The Inventory comprises eight subscales and a total of 54 items with a higher score indicating an environment which provides more possibilities for development and growth. Various statistical tests were carried out to determine the validity of the Inventory for use in the local context. These showed the Inventory to be internally consistent and to possess construct validity in particular the HOME Inventory had been validated in correlation tests with demographic variables such as social class index (F = 8.01, p less than 0.0001), people to room ratio (r = -0.37, p less than 0.0001) and a measure of IQ (r = 0.0003). Norms for local toddlers were also provided. It was concluded that the Inventory would play a useful role in detecting children who are physically and intellectually less advanced due to a poorer home environment. This finding could possibly be used in an intervention programme in ameliorating these conditions.

Child Care↗