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Relative validity effects with either one or two more valid cues in Pavlovian and instrumental conditioning.

Two experiments investigated the relative validity effect with either 1 or 2 continuously reinforced cues in Wistar rats using appetitive Pavlovian and instrumental preparations. Discrimination training involved 3 compound cues containing a common element (1AX: 1BX: 2CX). In the first true-discrimination group (TD-1), CX was followed by food, but AX and BX were not. In the second true-discrimination group (TD-2), AX and BX but not CX were followed by food. In the third, pseudodiscrimination group (PD), food followed 50% of each compound. Compared with the PD group, there were lower levels of responding to X in Groups TD-1 and TD-2, which did not differ. That is, both TD treatments showed equivalent relative validity effects. There was evidence for a relative validity effect on the context. The Rescorla-Wagner model incorrectly predicts a smaller relative validity effect after the TD-2 than the TD-1 treatment. Comparator theory predicts these results.

Animals↗

The quest for better validation: a critical comparison of the AAMI and BHS validation protocols for ambulatory blood pressure measurement systems.

Two validation procedures are currently available for the evaluation of ambulatory blood pressure measurement systems--the standard of the Association for the Advancement of Medical Instrumentation (AAMI) and the protocol of the British Hypertension Society (BHS). Both are in the process of revision. Four systems for measuring 24-hour ambulatory blood pressure--SpaceLabs 90207, Novacor DIASYS 200, Del Mar Avionics Pressurometer IV, and Takeda TM-2420--were evaluated according to the BHS protocol, which incorporates many of the features of the AAMI standard, under similar conditions by the same personnel and in the same subjects, so as to examine the relative merits of the two evaluation procedures. Three recorders of each model were subjected to a before-use inter-device variability test, followed by an in-use phase and an after-use inter-device variability test. The main validation test was carried out in 86 subjects with a wide range of pressures, the results being analyzed according to the BHS grading system and the AAMI validation criteria. The SpaceLabs 90207 and the DIASYS 200 achieved B and C grades, respectively, according to the BHS protocol and also satisfied the AAMI criteria for accuracy. The Pressurometer IV achieved a Grade C rating for systolic pressure and a Grade D rating for diastolic pressure and the Takeda TM-2420 achieved Grade D ratings for both systolic pressure and diastolic pressure. Both these devices failed to fulfil the AAMI criteria for accuracy and both failed to function in the main validation test and had to be replaced.(ABSTRACT TRUNCATED AT 250 WORDS)

Ambulatory Care↗

[Are blood glucose controls performed with portable dosimeters valid? A comparison of the reliability and validity of 3 commonly used models].

OBJECTIVE: To evaluate and compare the reliability and validity for both normal and high glycaemia values of three models of glycaemia self-analysers: Reflolux, Glucocard and One Touch. DESIGN: Descriptive and crossover study. Validation of a measuring appliance through its comparison with a standard appliance. PARTICIPANTS: The sample was composed of 90 blood specimens chosen by suitability sampling. MEASUREMENTS AND MAIN RESULTS: The glycaemia in the specimens was measured simultaneously by each one of the self-analysers and the central laboratory. There was high reliability (reproducibility) among the self-analysers, with correlation coefficients of 0.98, 0.97 and 0.98, with no statistically significant differences. As to intra-instrument reliability (repeatability), tested by analysing the variances of the differences, no statistically significant differences were found, except in the Glucocard self-analyser which lost precision at high glycaemia levels. Validity or accuracy, measured by the method of taking the average of the differences, showed a systematic bias in the Reflolux model, which had a value of 22.3 mg/dl above the reference model, and in the One Touch of -16.3 mg/dl. The Glucocard was the most accurate with a value of -1.78 mg/dl. CONCLUSIONS: Portable glycaemia dosimeters are very useful in following up diabetic patients because of their high reliability, but are not useful in the diagnosis of diabetes because of their lack of accuracy. Before beginning to use a portable dosimeter, its characteristics in terms of reliability and validity must be known, in order to evaluate correctly its findings.

Adult↗

Mixed group validation: a method to address the limitations of criterion group validation in research on malingering detection.

Mixed group validation (MGV) is offered as an alternative to criterion group validation (CGV) to estimate the true positive and false positive rates of tests and other diagnostic signs. CGV requires perfect confidence about each research participant's status with respect to the presence or absence of pathology. MGV determines diagnostic efficiencies based on group data; knowing an individual's status with respect to pathology is not required. MGV can use relatively weak indicators to validate better diagnostic signs, whereas CGV requires perfect diagnostic signs to avoid error in computing true positive and false positive rates. The process of MGV is explained, and a computer simulation demonstrates the soundness of the procedure. MGV of the Rey 15-Item Memory Test (Rey, 1958) for 723 pre-trial criminal defendants resulted in higher estimates of true positive rates and lower estimates of false positive rates as compared with prior research conducted with CGV. The author demonstrates how MGV addresses all the criticisms Rogers (1997b) outlined for differential prevalence designs in malingering detection research.

Adolescent↗

Content validity, construct validity, and reliability of the WHOQOL-Bref in a population of Dutch adult psychiatric outpatients.

In this study, the psychometric properties of a quality of life scale, the WHOQOL-Bref, were examined in a population of 533 Dutch adult psychiatric outpatients. Participants underwent two semistructured interviews in order to obtain Axis-I and II diagnoses, according to DSM-IV. Besides the WHOQOL-Bref they also completed questionnaires for measuring psychopathological symptoms (SCL-90) and perceived social support (PSSS). Scores on 25 of the 26 questions of the WHOQOL-Bref had a good distribution. Similar to previous findings, exploratory factor analysis revealed a four-factor structure. A priori expected associations were found between the domains of the WHOQOL-Bref, on the one hand, and dimensions of the SCL-90 and the PSSS-score, on the other hand, indicating good construct validity. The internal consistency of the four domains of the WHOQOL-Bref ranged from 0.66 to 0.80. Domain scores of the WHOQOL-Bref correlated around 0.92 with the WHOQOL-100 domain scores. Relatively low correlations were found between demographic characteristics (age and sex) and WHOQOL-Bref domain scores. It is concluded that the content validity, construct validity, and the reliability of the WHOQOL-Bref in a population of adult Dutch psychiatric outpatients are good. The WHOQOL-Bref, therefore, is an adequate measure for assessing quality of life at the domain level in a population of adult psychiatric outpatients.

Adult↗

Validation of high-performance liquid chromatography methods for pharmaceutical analysis. Understanding the differences and similarities between validation requirements of the US Food and Drug Administration, the US Pharmacopeia and the International Conference on Harmonization.

One of the most critical factors in developing pharmaceutical drug substances and drug products today is ensuring that the HPLC analytical test methods that are used to analyze the products generate meaningful data. The US Food and Drug Administration (FDA) and United States Pharmacopeia (USP) have each recognized the importance of this to the drug development process and have separately increased validation requirements in recent years. A third source, the International Conference on Harmonization (ICH), has added requirements that, when combined with the previous two sources, have led to three different sets of validation requirements leaving the industry in a state of confusion. This paper is written to clear up the confusion over the validation requirements that are presented by each of these three sources.

Chromatography, High Pressure Liquid↗

The validity of death certificates: routine validation of death certification and its effects on mortality statistics.

The 3478 death certificates (7.1% of all annual death certificates) of this study comprise those national death certificates in 1995 submitted for validation to the panel representing both medical and nosological expertise. As such, it is highly selected and represents, from the nosological point of view, the most inconsistently filled-in portion of Finnish death certificates. The routine validation procedure is essentially based on exploitation of the extra medical information, i.e. the case history, on the Finnish death certificate form. Altogether, 2813 (80.9%) out of 3478 certificates could be adjusted at the primary panel session; the rest required further clarification. The re-assignment of cause of death by the panel and the impact of panel adjustments on the national mortality statistics is assessed here by comparing the initial death certification and the finally registered underlying cause of death grouped into ICD-9 major categories with special reference to the subcategories of neoplasm, cardiovascular disease (HVD) and unnatural death. A statistically significant decline (p<0.0001) in deaths, both in the category of symptoms, signs and ill-defined conditions and in the pulmonary circulation disease subcategory of HVD with 37.6 and 35.1%, respectively, was observed. The decrease of 11.1% in the benign or NUD neoplasm subcategory and the increase of 8.6 and 7.0% in the categories of endocrine disease, and musculo-skeletal and connective tissue disease, respectively, are essential observations as to the quality of the cause of death register. The effect on the HVD major category was practically nil. At the HVD-subcategorial level, a decrease of 14.0% for diseases of the veins and lymphatics and other circulatory diseases and an increase of 3.5% for hypertensive diseases (HYP) were the two next most obvious alterations to the diseases of the pulmonary circulation, but were without statistical significance. For ischaemic heart disease and other subcategories, the effects were minor. The unnatural deaths as a whole increased in the final statistics with only 0.9%. In the study data, categorial changes ranged from the decrease of 75.2% for symptoms, signs and ill-defined conditions to the increase of 77.3% for endocrine diseases. In conclusion, the Finnish death certificate form, death certification practices and cause of death validation procedure seem to serve the coding of causes of death for mortality statistics appropriately. The results of the study form a relevant reference background to evaluation of epidemiological studies on mortality.

Abstracting and Indexing↗

Examining the construct validity of the original and revised JBS: a cross-validation of sample and method.

Factor analysis is a statistical technique that can provide an understanding of construct validity. Previous research examining the factor structure of the Juror Bias Scale (JBS) has uncovered problems in the scale's assessment of the constructs of probability of commission (PC) and reasonable doubt (RD). We here reevaluate the scale's constructs to better our understanding of the pretrial biases involved in the juror decision-making process. Importantly, previous findings have been limited to college student samples and trial material that has involved rape evidence. This study examines the construct validity of the JBS in a sample of 617 jury-eligible adults drawn from the community, and the predictive validity of the JBS is examined across 3 distinct trial scenarios. The results parallel earlier findings, indicating that although RD is a tenable and useful construct affecting juror decision-making, PC may be a less relevant pretrial bias. We therefore suggest that future research emphasize alternative constructs, such as confidence and cynicism in the criminal justice system.

Adolescent↗

Investigating the validity of the Draw-A-Person: Screening Procedure for Emotional Disturbance: a measurement validation study with high-risk youth.

This validity study examined the extent to which the Draw-A-Person: Screening Procedure for Emotional Disturbance (DAP:SPED; J. A. Naglieri, T. J. McNeish, & A. N. Bardos, 1991) was a significant predictor of behavioral functioning within a clinical sample of 68 latency-age children (6-12 years old) receiving counseling services at outpatient and residential treatment facilities. Study results showed that the total DAP:SPED (man, woman, and self scores summed) was a significant predictor in explaining variation in internalizing behavioral disturbance. Specifically, the DAP:SPED remained a moderate strength predictor of internalizing behavioral disturbance after controlling for the Child and Adolescent Adjustment Profile parent-report behavioral measure. Findings lend preliminary support to the DAP:SPED's validity in providing assessment information about child behavioral functioning. Continued validation investigation along these lines is recommended.

Affective Symptoms↗

On the validity of validity scales: the importance of defensive responding in the prediction of institutional misconduct.

This study examined the effects of defensive responding on the prediction of institutional misconduct among male inmates (N = 349) who completed the Personality Assessment Inventory (L. C. Morey, 1991). Hierarchical logistic regression analyses demonstrated significant main effects for the Antisocial Features (ANT) scale as well as main effects for the Positive Impression Management (PIM) scale in some instances. Significant ANT x PIM interactions also were evident, particularly when examining recommended cut scores on these scales. These results demonstrate the predictive validity of ANT with prisoners and reinforce the importance of context when considering whether validity scales are in fact valid.

Adult↗

vALId: validation of protein sequence quality based on multiple alignment data.

The validation of sequences is essential to perform accurate phylogeny and structure/function analysis. However among the thousands of protein sequences available in the public databases, most have been predicted in silico and have not systematically undergone a quality verification. It has recently become evident that they often contain sequence errors. To address the problem of automatic protein quality control, we have developed vALId, an interactive web interfaced software. Taking advantage of high quality multiple alignments of complete protein sequences (MACS), vALId first warns about the presence of suspicious insertions, deletions (indels) and divergent segments, and second, proposes corrections based on transcripts and genome contigs. In a first evaluation test, hundreds of indels and divergent segments were randomly generated in a manually refined MACS. The sensitivity (Sn) and specificity (Sp) of indel detection were excellent (0.96) while the mean Sn(0.49) and Sp(0.56) of divergent segment delineation depended on the percent identity between sequence neighbors. In a second test, 6195 sequences in 100 MACS corresponding to different functional and structural protein families were analyzed. 65% of the sequences were in silico predictions and 44% of eukaryote predicted proteins were partially incorrect with at least one suspicious indel or divergent segment.

Algorithms↗

Validation of the embryonic stem cell test in the international ECVAM validation study on three in vitro embryotoxicity tests.

A detailed report is presented on the performance of the embryonic stem cell test (EST) in a European Centre for the Validation of Alternative Methods (ECVAM)-sponsored formal validation study on three in vitro tests for embryotoxicity. Twenty coded test chemicals, classified as non-embryotoxic, weakly embryotoxic or strongly embryotoxic on the basis of their in vivo effects in animals and/or humans, were tested in four laboratories. The outcome showed that the EST can be considered to be a scientifically validated test, which is ready for consideration for use in assessing the embryotoxic potentials of chemicals for regulatory purposes.

Animal Testing Alternatives↗

Validation of the postimplantation rat whole-embryo culture test in the international ECVAM validation study on three in vitro embryotoxicity tests.

A detailed report is presented on the performance of the postimplantation rat whole-embryo culture (WEC) test in a European Centre for the Validation of Alternative Methods (ECVAM)-sponsored formal validation study on three in vitro tests for embryotoxicity. Twenty coded test chemicals, classified as non-embryotoxic, weakly embryotoxic or strongly embryotoxic on the basis of their in vivo effects in animals and/or humans, were tested in four laboratories. The outcome showed that the WEC test can be considered to be a scientifically validated test, which is ready for consideration for use in assessing the embryotoxic potentials of chemicals for regulatory purposes.

Animal Testing Alternatives↗

Detection of deception on the Schedule for Nonadaptive and Adaptive Personality: validation of the validity scales.

This study used a simulation design to investigate the validity scales of the Schedule for Nonadaptive and Adaptive Personality (SNAP). Undergraduates (N=192) were randomly assigned to two positive distortion (PD) groups, two negative distortion (ND) groups, and a control group. Controls responded normally, whereas the deception groups responded according to assigned characters. Preliminary analyses indicated no significant differences within distortion valence; thus, the groups were collapsed into single PD (n=76), ND (n=79), and control groups (n=37). Mean-level analyses revealed that, consistent with previous studies, ND profiles are easier to detect than PD profiles. Cutoff scores were suggested, and the classification accuracy of these scores converged with the results of several discriminant function analyses to indicate that Rare Virtues and Deviance predict group membership at least as well as MMPI-2 validity scales. Structural analyses revealed that two moderately correlated factors-positive distortion and negative distortion-underlie scores on these validity scales.

Adult↗

Interrater reliability, concurrent validity, responsiveness, and predictive validity of the Melville-Nelson Self-Care Assessment.

OBJECTIVE: This study examines psychometric characteristics of the Melville-Nelson Self-Care Assessment (SCA), which is designed for occupational therapists working in skilled nursing facilities (SNFs) and subacute rehabilitation. Like the federally mandated Minimum Data Set, the SCA assesses seven self-care occupations in two ways: self-performance and support needed. METHOD: Participants were SNF patients receiving subacute rehabilitation. Primary and secondary diagnoses varied widely; mean age was 76.5 years (SD = 9.8). Using the SCA, the Functional Independence Measure (FIM), and the Klein-Bell Activities of Daily Living Scale, four teams of raters independently and simultaneously assessed 54 women and 14 men at admission and discharge; 40 participants were available for reassessment in their homes after discharge. RESULTS: Total self-performance scores on the SCA showed (a) interrater reliability (mean ICC = .94); (b) concurrent validity with relevant areas of the FIM (rho = -.85) and the Klein-Bell (rho = -.86); (c) responsiveness in detecting change from admission to discharge, t(67) = 6.3, p < .001, with a large effect size of 1.10; and (d) moderate predictive validity of caregiving time in the home (rho = -.44) and overall function in the home as measured by the total FIM (rho = -.55) and total Klein-Bell (rho = -.54) scores. The self-performance and support measures for the seven self-care areas all had acceptable interrater reliability and concurrent validity. Eating, personal hygiene, and bathing showed little or no responsiveness to change from admission to discharge, whereas positive change was substantial in bed mobility, transfers, dressing, and toileting. CONCLUSION: This instrument is recommended for use as part of a comprehensive occupational therapy model of practice in SNFs and subacute rehabilitation.

Activities of Daily Living↗

Quality control including validation in dietary surveys of elderly subjects. The validation of a dietary history method (the SENECA-method) used in the 1914-population study in Glostrup of Danish men and women aged 80 years.

BACKGROUND: Quality control including validation in dietary surveys is needed to reduce and detect errors which would lead to an attenuated scientific foundation for the diet-disease relationship. Especially studies in the elderly are needed because of limited knowledge of reference values, cut-off values etc. OBJECTIVE: To validate a modified dietary history method (the SENECA-method) in elderly subjects. DESIGN: A survey of Danish men and women aged 80 years, who participated in the 1914-population study in Glostrup. SUBJECTS AND METHOD: A pilot study (n = 34) validated the dietary history against 24-h urine collections; a main study (n = 240) compared dietary history with a 3-day estimated food record. RESULTS: Protein intake from dietary history was 10% higher than calculated protein intake from 24-h urine collections. Differences in intakes of energy and macronutrients between dietary history and 3-day food record were generally small and non-significant, and there was good agreement between the methods in classifying nutrient intakes into same tertiles. A Bland & Altman plot indicated increasing differences in energy intake between methods with increased energy intake. Evidence for under-reporting of energy intake and/or over-reporting of the physical activity level was further made plausible when physical activity ratio was compared to recognized cut-off limits. CONCLUSIONS: The modified dietary history method can be used to estimate dietary intake in 80 year old subjects, but some degree of misreporting, especially under-reporting, appears to be present. Keeping this in mind it is, however, possible to analyse dietary intake against other survey data.

Aged↗

Internal validity of the disruptive behavior disorder symptoms: implications from parent ratings for a dimensional approach to symptom validity.

A dimensional approach was used to evaluate the internal validity of the DSM-III-R ADHD-inattention, ADHD-hyperactivity/impulsivity, oppositional defiant disorder (ODD), and conduct disorder (CD) symptoms (i.e., whether a symptom has a stronger correlation with its own dimension that the other three). Parents rated 4,019 children between the ages of 2 and 19 on these symptoms. The results showed that 5 of the 6 inattention symptoms, 3 of the 4 hyperactivity symptoms, 1 of the 4 impulsivity symptoms, 6 of the 9 oppositional defiant disorder symptoms, and 8 of the 11 CD symptoms had significant internal validity. Confirmatory factor analysis (CFA) found support for inattention, hyperactivity/impulsivity, oppositional defiant, and conduct disorder dimensions. Multiple-group CFA also found support for factor pattern and loading invariance across gender. The implications of these results as well as the merits of the dimensional approach to symptom validity are discussed in the context of the DSM-IV changes in ADHD, ODD, and CD.

Adolescent↗

Smoking outcome expectancies: factor structure, predictive validity, and discriminant validity.

Recent models of addiction posit that drug outcome expectancies are influential determinants of drug use. The current research examines the dimensional structure, predictive validity, and discriminant validity of expectancies for cigarette smoking in a prospective study. There was a good fit between the factor structure of the Smoking Consequences Questionnaire and the observed data. In addition, the internal consistency of each scale was satisfactory. Moreover, there was considerable evidence for the predictive and discriminant validity of expectancies. Expectancies of positive outcomes (positive reinforcement, negative reinforcement, and appetite-weight control) predicted withdrawal severity. Negative reinforcement expectancies and expectancies of negative consequences predicted cessation success. Predictive relations remained significant after controlling for related constructs: negative affect, stress, and dependence measures.

Adult↗