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PubMed1999

ECVAM and the Promotion of International Co-operation in the Development, Validation and Acceptance of Replacement Alternative Test Methods.

The European Centre for the Validation of Alternative Methods (ECVAM) was established by the European Commission in 1991, to co-ordinate the validation of alternative methods at the European Union level, to establish a database on alternative methods, and to promote dialogue among all the interested parties, in order to secure the international recognition and acceptance of validated alternative test methods. All ECVAM activities, including workshops, task forces, in-house laboratory studies, and contracted external pre-validation and validation studies, involve international co-operation. Of particular importance has been the role played by ECVAM, notably in partnership with ZEBET, in establishing the principles of test development, validation and acceptance, defining the practical procedures necessary to optimise the progress of new tests toward acceptance, and in successfully validating the 3T3 NRU PT test for phototoxic potential. It is vital that international co-operation goes beyond mere discussion and leads to definite collaborative projects, which lead, in turn, to genuine achievements.

Journal Article↗

PubMed1998

AGAATI/ECVAM Workshop on the Validation of Alternative Methods for the Potency Testing of Vaccines.

The workshop on validation of alternative methods for the potency testing of vaccines was organised by ECVAM (European Centre for the Validation of Alternative Methods) and AGAATI (Advisory Group on Alternatives to Animal Testing in Immunobiologicals), and it was held in Angera, Italy, on 14-16 November 1997 under the co-chairmanship of Coenraad Hendriksen (RIVM, Bilthoven, The Netherlands) and Jean-Marc Spieser (EDQM, Strasbourg, France). The 17 participants, all experts in vaccine quality control and/or validation procedures, came from international regulatory bodies and organisations, national control laboratories and vaccine manufacturers. The aim of the workshop was to discuss, in an informal atmosphere, the complex issue of guidelines for the validation of alternative methods to potency testing of vaccines in laboratory animals, in particular: a) to review existing guidelines for validation; b) to discuss specific guidelines for the validation of alternative methods to the potency testing of vaccines and to agree on strategies for the preparation of guidelines; and c) to discuss and make recommendations for the implementation of validated alternative methods for regulatory purposes. The outcome of the discussions and the recommendations will be published in the ECVAM workshop series in ATLA in late 1998.

Journal Article↗

PubMed2000

Reliability and validity of a Swedish version of Kogan's Old People Scale.

Standardized and well-tested instruments are needed in order to study attitudes toward old people. One scale that has been widely used is Kogan's Old People scale. A Swedish version of the scale has been available since 1987. The aim of this study was to test this Swedish version of the scale for reliability and validity, in a sample consisting of students and different health-care professionals. A convenience sample of 319 individuals in western Sweden took part in the study, and data were collected by means of a questionnaire that included the scale. Reliability was assessed as homogeneity and validity as construct validity. All but 4 of the 34 items were found to have significant item-total correlations. The Cronbach's alpha coefficient for the total scale was 0.79. Some evidence of construct validity was found in a three-factor solution, which explained 30% of the variances. Strong evidence of construct validity was shown in the scale's capability to differentiate between individuals who rather preferred to work with old people (p < 0.005) than with young clients. Convergent validity, as a form of construct validity, was also supported for the scale.

Aged↗

PubMed1992

Validity of repeated dietary measurements in a dietary intervention study.

The aim of the study was to evaluate the compliance in a dietary intervention study. When drawing conclusions about the relationship between dietary intake and disease occurrence/disease-related variables it is important to obtain valid dietary data. 20 healthy, non-smoking normal-weight omnivores changed from a mixed to a lactovegetarian diet. Dietary surveys (four 24 h recalls per person and time-period), urinary and faecal sample collections were performed before and 3, 6 and 12 months after the dietary shift. The validation of energy, protein, sodium and potassium yielded approximately the same ratio of dietary intake to biological marker at 0 and 3 months. This ratio decreased towards 6 months and continued to decrease towards 12 months. The fibre intake was compared to the total faecal weight directly and indirectly by calculating the fibre intake from the stool weight, the water content in faeces and the excretion of short-chain fatty acids (SCFAs). These four methods of fibre validation showed that the ratio of dietary intake to biological marker was always highest at 12 months, indicating an overestimation of the fibre intake at the end of the study. This is the first time these methods of validating fibre intake have been used in an epidemiological study. The ratio of dietary calcium intake to urinary and faecal calcium excretion did not show any statistical difference between the period before and 3 months after the dietary shift. To conclude, almost all investigated dietary data show approximately the same validity before and 3 months after the dietary shift, and show the least validity 12 months after the dietary shift. Thus, this study demonstrates that it is difficult to obtain valid dietary data 1 year after a drastic dietary change, indicating a decreased compliance to the new dietary regimen at the end of the 1 year study period. This represents important information when attempting to relate biological effects to dietary intake, and illustrates the importance of using biological markers for food intake in dietary surveys.

Adult↗

PubMed2003

Validation of sterilizing grade filtration.

Validation consideration of sterilizing grade filters, namely 0.2 micron, changed when FDA voiced concerns about the validity of Bacterial Challenge tests performed in the past. Such validation exercises are nowadays considered to be filter qualification. Filter validation requires more thorough analysis, especially Bacterial Challenge testing with the actual drug product under process conditions. To do so, viability testing is a necessity to determine the Bacterial Challenge test methodology. Additionally to these two compulsory tests, other evaluations like extractable, adsorption and chemical compatibility tests should be considered. PDA Technical Report # 26, Sterilizing Filtration of Liquids, describes all parameters and aspects required for the comprehensive validation of filters. The report is a most helpful tool for validation of liquid filters used in the biopharmaceutical industry. It sets the cornerstones of validation requirements and other filtration considerations.

Drug Industry↗

PubMed2003

Validation methodology in publications describing epidemiological registration methods of dental caries: a systematic review.

OBJECTIVE: The aim was to describe and systematically review the methodology and reporting of validation in publications describing epidemiological registration methods for dental caries. BASIC RESEARCH METHODOLOGY: Literature searches were conducted in six scientific databases. All publications fulfilling the predetermined inclusion criteria were assessed for methodology and reporting of validation using a checklist including items described previously as well as new items. The frequency of endorsement of the assessed items was analysed. Moreover, the type and strength of evidence, was evaluated. MAIN OUTCOME MEASURES: Reporting of predetermined items relating to methodology of validation and the frequency of endorsement of the assessed items were of primary interest. RESULTS: Initially 588 publications were located. 74 eligible publications were obtained, 23 of which fulfilled the inclusion criteria and remained throughout the analyses. A majority of the studies reported the methodology of validation. The reported methodology of validation was generally inadequate, according to the recommendations of evidence-based medicine. The frequencies of reporting the assessed items (frequencies of endorsement) ranged from four to 84 per cent. A majority of the publications contributed to a low strength of evidence. CONCLUSION: There seems to be a need to improve the methodology and the reporting of validation in publications describing professionally registered caries epidemiology. Four of the items assessed in this study are potentially discriminative for quality assessments of reported validation.

Dental Caries↗

PubMedDate not supplied

The modular analytical procedure and validation approach and the units of measurement for genetically modified materials in foods and feeds.

Food and feed analysts are confronted with a number of common problems, irrespective of the analytical target. The analytical procedure can be described as a series of successive steps: sampling, sample processing, analyte extraction, and ending, finally, in interpretation of an analytical result produced with, e.g., real-time polymerase chain reaction. The final analytical result is dependent on proper method selection and execution and is only valid if valid methods (modules) are used throughout the analytical procedure. The final step is easy to validate-the measurement uncertainty added from this step is relatively limited and can be estimated with a high degree of precision. In contrast, the front-end sampling and processing steps have not evolved much, and the corresponding methods are rarely or never experimentally validated according to internationally harmonized protocols. In this paper, we outlined a strategy for modular validation of the entire analytical procedure, using an upstream validation approach, illustrated with methods for genetically modified materials that may partially apply also to other areas of food and feed analyses. We have also discussed some implications and consequences of this approach in relation to reference materials, measurement units, and thresholds for labelling and enforcement, and for application of the validated methods (modules) in routine food and feed analysis.

Animal Feed↗

PubMed1992

[Adaptation and validation of a test on knowledge about diabetes mellitus].

OBJECTIVE: To adapt and validate a Spanish language medium test, of theoretical general knowledge of diabetes mellitus (questionnaire from the University of Michigan). To determine the validity of the concurrent and discriminatory content and establish reliability. DESIGN: The study was observational. Validity was verified prior to data collection. To analyse the concurrent and discriminatory validity, a questionnaire was used in personal interview with the patients, and the degree of knowledge evaluated on certain variables. SETTING: Hospital outpatient endocrinology consultations. PATIENTS: 167 diabetic patients were chosen at random, from the outpatient visits. 14 patients who had developed hearing, or language problems, or who had problems of a psychological nature, were excluded. Only 1 patient refused to answer the questionnaire. MAIN MEASUREMENTS AND RESULTS: Validity of the content was confirmed after careful analysis of the questions on the questionnaire by medical specialists in endocrinology. It was found that the test had adequate concurrence (p less than 0.01) when the average general knowledge levels of certain group of patients are compared. It also had acceptable discriminatory validity (r = 0.56: p less than 0.0001) and reliability (alpha: 0.84; p less than 0.45). CONCLUSIONS: Adaptation and validation has been obtained for a test of theoretical general knowledge on diabetes mellitus, and the test was found to be applicable to the population under study.

Adult↗

PubMed2004

[Validation and regulatory acceptance of alternative methods for toxicity evaluation].

For regulatory acceptance of alternative methods (AMs) to animal toxicity tests, their reproducibility and relevance should be determined by intra- and inter-laboratory validation. Appropriate procedures of the validation and regulatory acceptance of AMs were recommended by OECD in 1996. According to those principles, several in vitro methods like skin corrosivity tests and phototoxicity tests were evaluated and accepted by ECVAM (European Center for the Validation of Alternative Methods), ICCVAM (The Interagency Coordinating Committee on the Validation of Alternative Methods), and OECD. Because of the difficulties in conducting inter-laboratory validation and relatively short period remained until EU's ban of animal experiments for safety evaluation of cosmetics, ECVAM and ICCVAM have recently started cooperation in validation and evaluation of AMs. It is also necessary to establish JaCVAM (Japanese Center for the Validation of AM) to contribute the issue and for the evaluation of new toxicity tests originated in Japan.

Animals↗

PubMed2006

Validation of a questionnaire used to assess safety and professionalism among arborists.

This article summarizes a validation study of an instrument designed to measure safety and professionalism practices of arborists. A sample of 386 arborists from the State of Louisiana responded to the 58-item questionnaire. Analyses focused on several aspects of Messick's validation framework. Structural validity evidence was provided by analyses that indicate that the measures are unidimensional. Content validity evidence was supported by generally high positive values of the biserial correlations and optimal values of standardized mean-square item fit indices. Substantive validity evidence was provided by analyses that support the use of the two-point rating scale and a rank ordering of item means that is consistent with substantive theory. Person fit indices indicated little misfit among measures. Support for the generalizability aspect of validity was provided by an acceptable level of internal consistency and fairly tight error bands around estimated arborist measures. Additionally, few items exhibited DIF. Finally, with respect to the external aspect of validity, group differences between arborist measures were consistent with substantive theory.

Adult↗

PubMed1991

[Validation in the French language of an evaluation scale for family functioning (FACES III): a tool for research and for clinical practice].

Valid and reliable scales are necessary to describe the numerous factors associated with health status. Multiple studies have shown the impact of familial factors, i.e. family functioning (FF) on health indicators. As no scale exists in french to assess FF, we performed a study to validate the Family Adaptability and Cohesion Evaluation Scale (FACES III, Olson et al.) in french. This scale has a high level of validity and reliability and has been widely used. After 2 translations and back-translations and a pilot study to establish face validity, the final version was studied in 976 healthy subjects (457 families) who attended a preventive medical center in Nancy, France. Parents and adolescents each filled out two 20 item self-administered questionnaires. There were few missing values (0-3% per item). Construct validity was assessed by principal component factor analysis, which found the same two individualized axes as in the original scale. The reliability of the french version was excellent and comparable to Olson's scale. This study demonstrates the validity and reliability of a french version of FACES III in a french population. It provides researchers and clinicians in France with a validated instrument for assessing, in a quantified way, factors associated with family functioning that influence health status in adults, adolescents and children, particularly those with chronic diseases. This scale is especially useful for developing and evaluating health programs.

Adolescent↗

PubMed1982

Effect of peripheral anosmia in dogs trained as flavor validators.

The importance of olfaction in perception of flavor by flavor-validating dogs was studied. The flavor-validation technique is widely used by pet food manufacturers to determine if a given formula is perceived by dogs as having the flavor of a specific meat. Five Beagles were trained as flavor validators; 2 dogs were trained to select beef and 3 to select lamb from a panel of 4 meats. When the dogs had been trained to select the correct meat on 100% of the trials, they were made anosmic. Reversible peripheral anosmia was produced in the dogs by inflating a cuff on a surgically implanted tracheostomy tube. When the cuff was inflated, air entered the trachea via the tracheostomy tube, rather than via the nasal cavity, and the percentage of correct choices on the flavor-validating test fell to 62 +/- 14%. When the tracheostomy tubes were removed, performance returned to 100% correct. The nasal cavities of 3 dogs were infused with zinc sulfate to produce a more complete and longer-lasting anosmia. The percentage of correct choice on the flavor-validation test fell to 24 +/- 5%. These findings indicate that the flavor-validation test is based primarily on one sensory modality, that of olfaction; therefore, formulas selected by flavor-validating dogs may smell similar to the specific meat, but do not necessarily taste similar to that meat.

Administration, Intranasal↗

PubMed1995

Appropriateness of hospital utilization. The validity and reliability of the Intensity-Severity-Discharge Review System in a United Kingdom acute hospital setting.

Assessing the appropriateness of hospital utilization in the United Kingdom may yield practical solutions to problems faced by both purchasers and providers of health care in the National Health Service. It is, however, essential that such assessment is based on a method that is both valid and reliable--in particular, valid in the context in which it is applied. Whereas American methods for the assessment of appropriateness have been shown to be valid in the United States, it is pertinent to question whether the application of such methods to the National Health Service also is valid given the different circumstances, both cultural and financial, under which health care is provided. A study of the appropriateness of admission and hospital stay for a sample of admissions to a large acute hospital in the United Kingdom was carried out, and the assessment of appropriateness was made using the Intensity-Severity-Discharge Review System with Adult criteria (ISD-A). The validity and reliability of using the ISD-A for assessing hospital utilization in the United Kingdom was evaluated. The ISD-A was found to have high reliability and to be valid for assessing appropriateness in the United Kingdom when a full range of alternative forms of care are presumed to be available. It was not found to be valid currently, therefore, for routine assessment of hospital utilization within the National Health Service, when alternatives often are not available.

Emergencies↗

PubMed1994

Validation in the clinical process: four settings for objectification of the subjectivity of understanding.

Clinical material is presented for discussion with the aim of exemplifying the author's conceptions of validation in a number of sessions and in psychoanalytic research and of making them verifiable, susceptible to consensus and/or falsifiable. Since Freud's postscript to the Dora case, the first clinical validation in the history of psychoanalysis, validation has been group-related and society-related, that is to say, it combines the evidence of subjectivity with the consensus of the research community (the scientific community). Validation verifies the conformity of the unconscious transference meaning with the analyst's understanding. The deciding criterion is the patient's reaction to the interpretation. In terms of the theory of science, validation in the clinical process corresponds to experimental testing of truth in the sphere of inanimate nature. Four settings of validation can be distinguished: the analyst's self-supervision during the process of understanding, which goes from incomprehension to comprehension (container-contained, PS-->D, selected fact); the patient's reaction to the interpretation (insight) and the analyst's assessment of the reaction; supervision and second thoughts; and discussion in groups and publications leading to consensus. It is a peculiarity of psychoanalytic research that in the event of positive validation the three criteria of truth (evidence, consensus and utility) coincide.

Adult↗

PubMed1994

A comparison of the British Hypertension Society and Association for the Advancement of Medical Instrumentation protocols for validating blood pressure measuring devices: can the two be reconciled?

BACKGROUND: Experience with the original protocols of the Association for the Advancement of Medical Instrumentation (AAMI) and the British Hypertension Society (BHS) for validating blood pressure has provided valuable insight into the methodological problems associated with device validation and has influenced both the BHS and the AAMI in revising their protocols. OBJECTIVES: To review the revisions of the original BHS and AAMI protocols; to compare the protocols; and, using the BHS protocol as a framework for validation, to determine how it should be modified to a protocol that will fulfil the criteria of both the AAMI and the BHS. CONCLUSIONS: The revised protocols have many similarities but there are some important differences. These differences merit consideration so as to facilitate manufacturers seeking to validate devices for acceptance in both Europe and the United States. Of the two protocols, the BHS protocol is the more elaborate in that (1) it takes particular care to ensure that observers are trained to a very high standard, (2) it makes provision for special group validation and (3) it recommends in-use validation of all devices. By modifying the BHS protocol, it is possible to validate blood pressure measuring devices (ambulatory devices require special consideration) to satisfy the criteria of both protocols.

Blood Pressure Determination↗

PubMedDate not supplied

The validation life cycle.

The Validation Life Cycle is an implementation mechanism which can assist pharmaceutical (and other types of medical product) manufacturers in the organization and execution of validation activities. A considerable body of work exists which identifies how to validate processes of various type and description. Unfortunately, there is a paucity of information on how to organize these individual validation activities into a cohesive whole. This paper describes a suggested means for achieving an organization's validation goals in a rational and effective fashion. To best understand the advantages of a life cycle for validation, a recap of the history of validation in the U.S. pharmaceutical industry is useful.

Computers↗

PubMed1996

Validation of the French version of the arthritis impact measurement scales 2 and comparison with the french version of the Nottingham Health Profile. "Quality of Life in Rheumatology" Task Force.

Appropriate attention can be directed to quality of life indices in the evaluation of therapeutic interventions only if reliable, valid measurement tools with good sensitivity to change are available. The goal of this study was to validate the French version of the Arthritis Impact Measurement Scales 2 (AIMS2), called EMIR (Echelle de Mesure de l'Impact de la polyarthrite Rhumatoïde) and to compare it with the validated French version of the Nottingham Health Profile, called ISPN (Indicateur de Santé Perceptuelle de Nottingham). The French version of the AIMS2 (37 items, 12 dimensions) was obtained via several independent translations and back-translations, followed by selection of the most relevant items by a panel of experts and a preliminary evaluation in rheumatoid arthritis patients. The measurement properties of EMIR (reliability, validity and sensitivity to change) were investigated in a cohort of rheumatoid arthritis patients who were put under methotrexate therapy and followed up for six months. Reliability was evaluated by test-retest at a ten-day interval (intraclass coefficients of correlation). Principal component factorial analysis was used to study construct validity and Cronbach's alpha coefficients to study internal consistency. Convergent validity was evaluated based on correlations between the quality of life scores obtained in selected dimensions of the EMIR and a number of other parameters (number of painful/swollen joints, pain severity score on a visual analog scale, erythrocyte sedimentation rate). Sensitivity to change after three and six months was determined by calculating mean standardized response means. The EMIR and ISPN were compared based on scores and sensitivity to change for the dimensions that investigated the same concepts. One hundred twenty-seven rheumatoid arthritis patients scheduled for methotrexate therapy were entered into the study. Principal component analysis established that all dimensions of the EMIR were independent from one another, except the "walking and bending" dimension. Internal consistency was satisfactory for each of the 12 dimensions, with Cronbach's alpha coefficients ranging from 0.70 to 0.90. Most correlations between quality of life scores and clinical or laboratory parameters were significant, indicating satisfactory convergent validity. The reliability study also yielded satisfactory results, with intraclass coefficients ranging from 0.65 to 0.90. Sensitivity to change after three and six months was significant for 11 of the 12 dimensions (mean standardized responses, 0.30 to 0.77). Sensitivity to change was slightly better for the EMIR than for the ISPN. Analysis of scores demonstrated that these two instruments did not measure quality of life in exactly the same way but complemented each other.

Adult↗

PubMed1996

The development and validation of a measure of parent-reported child health and morbidity: the Warwick Child Health and Morbidity Profile.

OBJECTIVE: to validate a simple instrument for the measurement of parent-reported health and morbidity in infancy and childhood suitable for research and service planning purposes and capable of measuring both cross-sectional and longitudinal health and morbidity experience in a child population. SETTING: child health clinic (CHC), child development unit (CDU) and paediatric outpatient department (OPD) in Coventry. DESIGN: 3-phase field testing to establish test-retest reliability, validity and inter-observer variation of the instrument. Field testing samples: phases 1 and 2; 188 parents of pre-school children attending one of the three health service settings-CHC, CDU or paediatric OPD; phase 3; 40 parents of pre-school children attending CHCs. METHODS: test-retest reliability of each domain of the WCHMP was estimated using weighted Kappa; criterion validity was estimated for selected domains against health records; construct validity against medically plausible constructs was tested by comparing responses between domains; Inter-observer variation was estimated using weighted Kappa. RESULTS: the test-retest reliability of the WCHMP varied from 'moderate' for behaviour, functional health and life quality status to 'very good' for acute significant illness and hospital admission status; criterion and construct validity were high; weighted Kappas for all domains for inter-observer variation between the researcher and family health visitor were in the 'good' to 'very good' range and inter-observer variation remained unaffected by change in the order of administration of the WCHMP. CONCLUSIONS: the WCHMP is a simple measure of parent-reported health and illness which, on field-testing, has been shown to be reliable and valid with low inter-observer variation. After further development and validation including incorporation into the parent-held record, it should be suitable for use in infancy and early childhood to collect cross-sectional and longitudinal health and morbidity data for research and service planning purposes.

Chi-Square Distribution↗