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PubMed2005

Design and validation of a methodology using the International Classification of Diseases, 9th Revision, to identify secondary conditions in people with disabilities.

OBJECTIVE: To design and validate a methodology that identifies secondary conditions using International Classification of Disease, 9th Revision (ICD-9) codes. DESIGN: Secondary conditions were identified through a literature search and a survey of Washington State physiatrists. These conditions were translated into ICD-9 codes and this list was then validated against a national sample of Medicare survey respondents with differing levels of mobility and activities of daily living (ADL) disability. SETTING: National survey. PARTICIPANTS: Participants (N=9731) in the 1999 Medicare Current Beneficiary Survey with no, mild, moderate, and severe mobility and ADL disability. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Percentage of survey respondents with a secondary condition. The secondary conditions were grouped into 4 categories: medical, psychosocial, musculoskeletal, and dysphagia related (problems associated with difficulty in swallowing). RESULTS: Our literature search and survey of 26 physiatrists identified 64 secondary conditions, including depression, decubitus ulcers, and deconditioning. Overall, 70.4% of all survey respondents were treated for a secondary condition. We found a significant relation between increasing mobility as well as ADL disability and increasing numbers of secondary conditions (chi 2 test for trend, P <.001). This relation existed for all categories of secondary conditions: medical (chi 2 test for trend, P <.001), psychosocial (chi 2 test for trend, P <.001), musculoskeletal (chi 2 test for trend, P <.001), and dysphagia related (chi 2 test for trend, P <.001). CONCLUSIONS: We created a valid ICD-9-based methodology that identified secondary conditions in Medicare survey respondents and discriminated between people with different degrees of disability. This methodology will be useful for health services researchers who study the frequency and impact of secondary conditions.

Disability Evaluation↗

PubMedDate not supplied

SisPorto 2.0: a program for automated analysis of cardiotocograms.

OBJECTIVE: To describe the latest version of SisPorto, a program for automated analysis of cardiotocograms that closely follows the FIGO guidelines, analyses ante- and intrapartum tracings, performs no signal reduction, and has the possibility of simultaneously recording twins. METHODS: A detailed description of the program's processing algorithms and operation is provided, as well as the main results of the studies performed to-date with this system. RESULTS: Considering both current and previous versions of the program, SisPorto has been tested in over 6000 pregnancies. The system's FHR baseline was compared with an average of three experts' estimates, and the difference was under 8 bpm in all cases. A fair to good agreement was found with experts' identification of accelerations, decelerations, contractions, and normal/reduced variability (proportions of agreement 0.64-0.89). In a preliminary validity study (n = 85), a sensitivity of 100% and a specificity of 99% were obtained in prediction of poor neonatal outcome. The system is currently undergoing an international multicentre validation study. CONCLUSIONS: Although still at the research level, a considerable experience has now been gathered with this system. Promising results have been achieved in studies comparing SisPorto with experts' analysis and in those evaluating the validity of the system.

Algorithms↗

PubMed1991

Validation of biological markers for quantitative risk assessment.

The evaluation of biological markers is recognized as necessary to the future of toxicology, epidemiology, and quantitative risk assessment. For biological markers to become widely accepted, their validity must be ascertained. This paper explores the range of considerations that compose the concept of validity as it applies to the evaluation of biological markers. Three broad categories of validity (measurement, internal study, and external) are discussed in the context of evaluating data for use in quantitative risk assessment. Particular attention is given to the importance of measurement validity in the consideration of whether to use biological markers in epidemiologic studies. The concepts developed in this presentation are applied to examples derived from the occupational environment. In the first example, measurement of bromine release as a marker of ethylene dibromide toxicity is shown to be of limited use in constructing an accurate quantitative assessment of the risk of developing cancer as a result of long-term, low-level exposure. This example is compared to data obtained from studies of ethylene oxide, in which hemoglobin alkylation is shown to be a valid marker of both exposure and effect.

Biomarkers↗

PubMed1986

Classifying and coding morbidity in general practice: validity and reliability in an international trial.

An international field trial of the draft defined version of the International Classification of Health Problems in Primary Care (ICHPPC) was undertaken in nine countries. Fifty-two physicians coded morbidity in 76 standard written clinical vignettes. The validity and reliability of morbidity coding using the defined classification and the extent to which these might be improved by using definitions have been estimated. There was an average of 1.7 problems per encounter, for a total of 807 different problems recorded. Sixty-two percent of the problems were coded correctly. The majority of incorrectly recorded problems were due to varied minority views of the contents of the encounters and to mistakes in recording code numbers. The results of morbidity surveys are useful only if the methods of gathering, recording, coding, collating, and analyzing the data are explicit and well documented. This study illustrates the difficulties of recording morbidity in general practice encounters. Better use of definitions and the addition of an index could improve coding accuracy.

Australia↗

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↗

PubMed1999

Measurement of health-related quality of life in patients with amyotrophic lateral sclerosis in clinical trials of new therapies.

OBJECTIVES: Recent trials of amyotrophic lateral sclerosis (ALS) therapies have included the Sickness Impact Profile (SIP) to evaluate health-related quality of life (HQL). The purpose of this study was to assess the feasibility, psychometric properties, and interpretation of the Sickness Impact Profile in this setting. METHODS: The Sickness Impact Profile was administered at baseline, 3, 6, and 9 months during a double-blind, placebo-controlled study of recombinant human insulin-like growth factor I. The frequency of missing Sickness Impact Profile data and administration time were recorded. Patients' scores on the Appel ALS (AALS) Rating Scale were used to identify a stable subgroup for reliability testing and clinically distinct groups for validity testing. Internal consistency reliability and reproducibility were evaluated using Cronbach's alpha and intraclass correlation coefficients, respectively. Analysis of variance (ANOVA) models and t tests were used to assess validity. Effect sizes and the responsiveness index were used to assess responsiveness. RESULTS: At baseline, 259 (97%) patients completed a 30-minute Sickness Impact Profile interview. At subsequent assessments, response rates ranged from 92% to 97% and mean administration times ranged from 25 to 27 minutes. The overall Sickness Impact Profile score demonstrated alpha reliability and 3-month stability coefficients of 0.94 and 0.80, respectively. Baseline overall Sickness Impact Profile scores discriminated between patients in the two AALS-defined groups with a mean of 13.0+/-7.8 and 24.0+/-11.7 in the better and worse AALS groups, respectively. Similarly, mean overall SIP change scores discriminated patients progressing at different rates (slow to moderate = 4.00+/-7.97; rapid = 10.74+/-8.76). With few exceptions, dimension and category scores met similar criteria. Responsiveness statistics for the physical and overall Sickness Impact Profile scores were lower at 3 months and higher at 6 and 9 months. CONCLUSIONS: The feasibility, psychometric, and interpretive findings support the validity of the Sickness Impact Profile for assessing outcomes of amyotrophic lateral sclerosis and its treatment. Based on these findings, we recommend including the Sickness Impact Profile in future amyotrophic lateral sclerosis clinical trials.

Activities of Daily Living↗

PubMed1997

Childbirth confidence: validating the Childbirth Self-Efficacy Inventory (CBSEI) in an Australian sample.

This study examined the reliability and validity of the Childbirth Self-Efficacy Inventory (CBSEI) (Lowe 1993) in a sample of 100 Australian women. Consistent with US data, the measure was shown to have high internal consistency. Validity of the instrument was determined by applying self-efficacy theory (Bandura 1982), which predicts that parity should have the largest effect on childbirth self-efficacy, followed by knowledge, then support and finally anxiety. Results revealed that having prior good birth experience and knowledge about childbirth had significant effects on childbirth self-efficacy. A factor analysis was performed to determine whether the original factor structure of this instrument held for Australian women. While outcome expectancies and self-efficacy expectancies emerged as distinct factors, the results showed that Australian women did not differentiate between active and second-stage labour. Rather than the two stages of labour emerging as dimensions of the CBSEI, two externally focused coping strategies were revealed.

Adaptation, Psychological↗

PubMed1989

Predictive validity of certification by the American Board of Internal Medicine.

STUDY OBJECTIVE: To determine the predictive validity of the American Board of Internal Medicine (ABIM) certification process. DESIGN: Prospective measurement of the knowledge, skills, and attitudes of 185 ABIM-certified and 74 noncertified internists by a written examination; evaluation by professional associates; a patient questionnaire assessing satisfaction with care, physician's counseling role, and preventive care; and review of records of patients with common illnesses. SUBJECTS: Practicing internists who completed training or received ABIM certification 5 to 10 years previously. SETTING: Office-based practices in six western states. RESULTS OF DATA ANALYSIS: Physicians certified by the ABIM had significantly higher scores on the written examination than the noncertified physicians, and scores on our examination correlated highly with the ABIM certification examination (r = 0.73). Ratings of clinical skills by professional associates were significantly higher for certified internists and also correlated highly with ABIM examination scores (r = 0.53 to 0.59). Regression analysis showed that ABIM certification status was the major variable affecting performance on these measures of clinical competence. Results from other measures did not show many differences between certified and noncertified physicians in the care of patients with common illnesses, but modest differences in preventive care and a few differences in outcome favored the certified physicians. CONCLUSIONS: Comparison of findings from the written examination and the professional associate ratings with certification status and original ABIM certification examination scores shows predictive validity of ABIM certification. Further studies are needed to determine if certification status predicts important differences in the care of patients with complex illnesses.

Certification↗

PubMed1997

Association of the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index with measures of disease activity and health status in patients with systemic lupus erythematosus.

OBJECTIVE: To examine the internal consistency and validity of the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI) with respect to disease activity, health status, and medication score. METHODS: A prospective cross sectional study of patients with systemic lupus erythematosus (SLE) attending a specialist lupus outpatient clinic between July 1994 and February 1995. The internal consistency of the SDI components was examined using Cronbach's coefficient alpha. The associations of the SDI components with disease activity measured by the British Isles Lupus Assessment Group (BILAG) index, health status measured by the Medical Outcomes Study (MOS) Short Form 20, and with a medication score were analyzed using Spearman's rank correlation coefficient (p). RESULTS: 133 women and 8 men ranging in age from 20.1 to 88.7 years (mean 41.1, SD 12.5) were studied. With few exceptions, the components of the SDI that reflect damage in different organ systems were not associated with each other. We found a significant although weak relationship between some related SDI and BILAG components (p 0.25 to 0.28; p < 0.01). While damage to the musculoskeletal system was associated with limitations in physical functioning measured with the MOS Short Form 20 (p-0.30; p < 0.01) and renal damage inversely with fatigue (p-0.23; p < 0.01) there was no significant relationship of other SDI components with the MOS Short Form 20. Renal and neuropsychiatric damage were associated significantly with the medication score (p 0.27 and 0.23; p < 0.01). CONCLUSION: The components of the SDI are valid in that they are associated with disease activity in the respective organ systems and some of them with a medication score. However, damage in different organ systems in SLE does not follow a common pattern. It is thus suggested that the SDI profile be used in addition to the SDI total score as an endpoint in clinical and epidemiological studies.

Adult↗

PubMed1994

[The new international psychiatric classification system, ICD-10. II. New classification systems in psychiatry].

The different interpretations of the concept of "mental disease" and the absence of an etiopathogenetic plane in the area of mental disorders led to the creation of descriptive (phenomenological) classifications of mental disorders. Their main representatives are the American diagnostic and statistical manual of mental disorders, DSM-III, its revised version DSM-III-R and the new international classification of mental disorders iCD-10. Both systems use a common theoretical baseline and are to a considerable extent compatible. Typically they have a high reliability and low validity of diagnostic categories. Subsequent development of psychiatric classifications will be focused in particular on improvement of diagnostic validity. The international psychiatric classification was created in different versions for the purpose of specialized psychiatric care, primary care and for research.

Humans↗

PubMed2006

Statistical external validation and consensus modeling: a QSPR case study for Koc prediction.

The soil sorption partition coefficient (log K(oc)) of a heterogeneous set of 643 organic non-ionic compounds, with a range of more than 6 log units, is predicted by a statistically validated QSAR modeling approach. The applied multiple linear regression (ordinary least squares, OLS) is based on a variety of theoretical molecular descriptors selected by the genetic algorithms-variable subset selection (GA-VSS) procedure. The models were validated for predictivity by different internal and external validation approaches. For external validation we applied self organizing maps (SOM) to split the original data set: the best four-dimensional model, developed on a reduced training set of 93 chemicals, has a predictivity of 78% when applied on 550 validation chemicals (prediction set). The selected molecular descriptors, which could be interpreted through their mechanistic meaning, were compared with the more common physico-chemical descriptors log K(ow) and log S(w). The chemical applicability domain of each model was verified by the leverage approach in order to propose only reliable data. The best predicted data were obtained by consensus modeling from 10 different models in the genetic algorithm model population.

Algorithms↗

PubMed2003

Quantitative determination of benazepril and benazeprilat in human plasma by gas chromatography-mass spectrometry using automated 96-well disk plate solid-phase extraction for sample preparation.

An analytical method for the determination of benazepril and its active metabolite, benazeprilat, in human plasma by capillary gas chromatography-mass-selective detection, with their respective labelled internal standard, was developed and validated according to international regulatory requirements. After addition of the internal standards, the compounds were extracted from plasma by solid-phase extraction using automated 96-well plate technology. After elution, the compounds were converted into their methyl ester derivatives by means of a safe and stable diazomethane derivative. The methyl ester derivatives were determined by gas chromatography using a mass-selective detector at m/z 365 for benazepril and benazeprilat and m/z 370 for the internal standards. Intra- and inter-day accuracy and precision were found to be suitable over the range of concentrations between 2.50 and 1000 ng/mL.

Benzazepines↗

PubMedDate not supplied

Validated QSAR prediction of OH tropospheric degradation of VOCs: splitting into training-test sets and consensus modeling.

The rate constant for hydroxyl radical tropospheric degradation of 460 heterogeneous organic compounds is predicted by QSAR modeling. The applied Multiple Linear Regression is based on a variety of theoretical molecular descriptors, selected by the Genetic Algorithms-Variable Subset Selection (GA-VSS) procedure. The models were validated for predictivity by both internal and external validation. For the external validation two splitting approaches, D-optimal Experimental Design and Kohonen Artificial Neural Networks (K-ANN), were applied to the original data set to compare the two methodologies. We emphasize that external validation is the only way to establish a reliable QSAR model for predictive purposes. Predicted data by consensus modeling from different models are also proposed.

Journal Article↗

PubMed2003

A principal components analysis of the Autism Diagnostic Interview-Revised.

OBJECTIVE: To develop factors based on the Autism Diagnostic Interview-Revised (ADI-R) that index separate components of the autism phenotype that are genetically relevant and validated against standard measures of the constructs. METHOD: ADIs and ADI-Rs of 292 individuals with autism were subjected to a principal components analysis using VARCLUS. The resulting variable clusters were validated against standard measures. RESULTS: Six clusters of variables emerged: spoken language, social intent, compulsions, developmental milestones, savant skills and sensory aversions. Five of the factors were significantly correlated with the validating measures and had good internal consistency, face validity, and discriminant and construct validity. Most intraclass correlations between siblings were adequate for use in genetic studies. CONCLUSION: The ADI-R contains correlated clusters of variables that are valid, genetically relevant, and that can be used in a variety of studies.

Adolescent↗

PubMed1997

A seven item scale for the assessment of disabilities after child and adolescent injuries.

OBJECTIVES: To develop a scale to assess physical disabilities after child or adolescent injuries. SETTING: The three main hospitals of Jerusalem. METHODS: Telephone interviews pertaining to the injury's effect on the functioning of children 4-17 years old (n = 281) were carried out six months after an injury. Disabilities were recalled by the parents for the period immediately after the injury (short term) and at the time of interview (long term). Of 25 questions derived from the International Classification of Impairments, Disabilities and Handicaps, seven were selected: limitations in walking, running, getting up/lying down, moving in bed, going to the toilet, bathing/keeping personal hygiene, and dressing. Construct validity was tested using the usual, sport, school, and leisure time activities as the gold standard. RESULTS: The prevalence of short term disabilities ranged from 23.8% to 37.7% and of long term disabilities from 0.4% to 11.8%. Cronbach's alpha was 0.91 for the short term scale and over 0.90 for the different categories of the sociodemographic variables. It decreased to 0.66 for the long term scale. Sensitivity of the short term scale ranged from 77% to 89%, but was lower for the long term scale. Specificity varied from 72% to 84% and increased to 88% to 90%, six months after the injury. CONCLUSIONS: This scale could be used to study disability after injury among children and adolescents in different cultures. It is a simple method that does not require expert personnel and has relatively high validity and internal reliability.

Adolescent↗

PubMed2006

German short forms of the Oral Health Impact Profile.

OBJECTIVES: We report the development and psychometric evaluation of short forms of the Oral Health Impact Profile German version (OHIP-G) - an instrument to assess oral health-related quality of life (OHRQoL). METHODS: A five-item short form was developed using best subset regression in 2050 subjects from a national survey. Two 14-item versions were derived from English-language short forms and a 21-item version from previous factor analytic work. A second sample from the general population (n = 163) and a sample of clinical patients with temporomandibular disorders (TMD; n = 175) were used to investigate validity and internal consistency. Test-retest reliability was evaluated in 30 prosthodontic patients before treatment. Responsiveness was assessed in 67 patients treated for their TMD pain. RESULTS: Associations between short form summary scores and self-report of oral health and four oral disorders in the general population and in TMD patients were interpreted as support for convergent/groups validity. The instruments' responsiveness (effect measures of 0.55-0.98), test-retest reliability (intraclass correlation coefficients: 0.72-0.87), and internal consistency (Cronbach's alpha: 0.65-0.92) were sufficient. CONCLUSIONS: Sufficient discriminative and evaluative psychometric properties of short forms of the OHIP-G make the instruments suitable to assess OHRQoL in cross-sectional as well as longitudinal studies.

Adolescent↗

PubMed2006

Detection of depression in women of child-bearing age in non-Western cultures: a comparison of the Edinburgh Postnatal Depression Scale and the Self-Reporting Questionnaire-20 in Mongolia.

BACKGROUND: This study assesses, for the first time, the validity and internal reliability of the Edinburgh Post Natal Depression Scale (EPDS) and the WHO Self-Reporting Questionnaire 20-item version (SRQ-20) in detecting depression in Mongolian women of reproductive age. METHODS: 100 women age recruited from two psychiatric units specialising in depression (n = 55) and three community-based child immunisation clinics (n = 45) in Ulaanbataar, Mongolia, were formally psychiatrically assessed by a clinician and by administering the revised Clinical Interview Schedule (CIS-R). Each woman also completed the EPDS and SRQ-20. RESULTS: Ninety four women provided complete data and identical optimal cut-off points for both the EPDS (11.5) and SRQ-20 (8.5) were determined against both the psychiatrist's and CIS-R based diagnosis using standard validation parameters. On all parameters the SRQ-20 performed better than the EPDS. The sensitivity of the SRQ-20 in detecting depression was 93% and the specificity 97% against the psychiatrist's diagnosis. Internal reliability was satisfactory. LIMITATIONS: The use of a mixed clinical and community sample for validation, and a single psychiatrist may limit the generalisability of these results. CONCLUSIONS: The SRQ-20 performed well and better than the EPDS in detecting depression in this group of Mongolian women.

Adolescent↗

PubMed1998

[Perceived quality of life of elderly somatic nursing-home patients. Construction of a measuring instrument].

An instrument to assess perceived quality of life of physically frail elderly persons is needed in nursing home research. Four existing instruments (Pain, Somatic Autonomy, Life Satisfaction, Social Isolation) and two new scales (Perceived Safety, Perceived Autonomy) were tested for internal consistency, validity of the dimensional structure, discriminatory power, and feasibility. The scales were administered to 243 physically frail elderly nursing home patients. Three of the existing scales were shown to have sufficient internal consistency (KR-20 > .70), and the two new scales were moderately consistent (KR-20 > .50). The expected dimensions were confirmed in general by principal component analysis of the items. Significant group differences were detected by means of scale means. The mean administration time was 20 minutes. It is concluded that feasible instrument has been developed that can be applied in future research in nursing homes.

Activities of Daily Living↗