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Development of the chronic obstructive pulmonary disease activity rating scale: reliability, validity and factorial structure.

The purpose of the present study was to develop the Chronic Obstructive Pulmonary Disease (COPD) Activity Rating Scale (CARS) to measure life-related activity in patients with COPD, and to confirm its reliability and constructive validity in a factorial structure model. The subjects consisted of 114 patients with COPD. An 88-item life-related activity list, generated previously from a literature review, was administered. The secondary structural model consisted of four factors with 12 items. The results of the confirmatory factor analysis by structural equation modeling showed the fit criteria to be statistically significant. The internal consistency of the 12 items was highly reliable (Cronbach's alpha = 0.924). The CARS score was correlated with pulmonary function tests, breathlessness, and the health-related quality of life (QOL) scales in Pearson correlation coefficient. The results suggest that the COPD Activity Rating Scale is a valid scale for the assessment of life-related activity in patients with COPD.

Activities of Daily Living↗

The Herdecke Questionnaire on Quality of Life (HLQ): validation of factorial structure and development of a short form within a naturopathy treated in-patient collective.

BACKGROUND: Quality of life (QoL) of patients has become a central evaluation parameter that also acts as an aid for decisions related to treatment strategies particularly for patients with chronic illnesses. In Germany, one of the newer instruments attempting to measure distinct QoL aspects is the "Herdecke Questionnaire for Quality of Life" (HLQ). In this study, we aimed to validate the HLQ with respect to its factorial structure, and to develop a short form. The validation has been carried out in relation to other questionnaires including the SF-36 Health Survey, the Mood-Scale Bf-S, the Giessen Physical Complaints Questionnaire GBB-24 and McGill's Pain Perception Scale SES. METHODS: Data for this study derived from a model project on the treatment of patients using naturopathy methods in Blankenstein Hospital, Hattingen. In total, 2,461 patients between the ages of 16 and 92 years (mean age: 58.0 +/- 13.4 years) were included in this study. Most of the patients (62%) suffered from rheumatic diseases. Factorial validation of the HLQ, it's reliability and external consistency analysis and the development of a short form were carried out using the SPSS software. RESULTS: Structural analysis of the HLQ-items pointed to a 6-factor model. The internal consistency of both the long and the short version is excellent (Cronbach's alpha is 0.935 for the HLQ-L and 0.862 for the HLQ-S). The highest reliability in the HLQ-L was obtained for the "Initiative Power and Interest" scale, the lowest for the 2-item scales "Digestive Well-Being" and the "Physical Complaints". However, the scales found by factor analysis herein were only in part congruent with the original 5-scale model which was approved a multitrait analysis approach. The new instrument shows good correlations with several scales of other relevant QoL instruments. The scales "Initiative Power and Interest", "Social Interaction", "Mental Balance", "Motility", "Physical Complaints", "Digestive Well-Being" sufficiently differentiate the diagnostic groups, particularly between the patients suffering on connective tissue and soft tissue disorders from those with metabolic and nutritional disorders or hypersensitivity reactions. CONCLUSION: Both the factorial validation and the development of a consistent short-form of the HLQ are important steps forward for researchers in the field of QoL who wish to use the HLQ as a reliable and valid instrument. The results indicate that the HLQ is a unique QoL-instrument that can be used for both in-patient and out-patient-treatment. However, to improve to profile of the HLQ, there is still the need for strengthening the Questionnaire in the dimensions of physical well-being. This is the subject of a separate ongoing study.

Adolescent↗

Quantifying clinical judgment in the assessment of adolescent psychopathology: Reliability, validity, and factor structure of the Child Behavior Checklist for clinician report.

The aim of this study was to assess the reliability and validity of the Child Behavior Checklist (CBCL) as completed by doctoral-level clinicians in the treatment of adolescents. We asked 294 randomly selected, experienced psychiatrists and psychologists to describe a patient aged 14 to 18 in treatment for personality pathology. Clinicians completed the CBCL (parent-report version) and measures of adaptive functioning, personality pathology, and family and developmental history, which served as criterion variables to test the validity of the CBCL as completed by clinicians. Most CBCL scales demonstrated acceptable reliability. Validity estimates were impressive, and the data revealed clinically meaningful associations between specific CBCL scale scores and developmental and family history variables. Confirmatory factor analysis showed that the factorial structure of the clinician-report CBCL resembled that of the parent-report CBCL, with the exception of a substantially lower correlation between higher order internalizing and externalizing factors. The data suggest that clinical judgment can be both reliable and valid when quantified using psychometrically sound instruments.

Adolescent↗

AutoDep: a web-based system for deposition and validation of macromolecular structural -information.

This paper describes the design and full implementation of a new concept in data deposition and validation: AutoDep (copyright Brookhaven Science Associates LLC). AutoDep changes the traditional procedure for data acceptance and validation of the primary databases into an interactive depositor-driven operation which almost eliminates the delay between the acceptance of the data and its public release. The system takes full advantage of the knowledge and expertise of the experimenters, rather than relying on the database curators for the complete and accurate description of the structural experiment and its results. AutoDep, developed by the Protein Data Bank at Brookhaven National Laboratory (BNL) as a flexible and portable system, has already been adopted by other primary databases and implemented on different platforms/operating systems. AutoDep was introduced at BNL in 1996 [see Manning (1996), Protein Data Bank Quart. Newslett. 77, 2 (ftp://ftp.rcsb. org/pub/pdb/doc/newsletters/bnl/newsletter96jul/newslttr+ ++.txt); Manning (1996), Protein Data Bank Quart. Newslett. 78, 2 (ftp://ftp. rcsb.org/pub/pdb/doc/newsletters/bnl/newsletter96oct/+ ++newslttr.txt)].

Computer Security↗

Establishment and functional validation of a structural homology model for human DNA methyltransferase 1.

Changes in DNA methylation patterns play an important role in tumorigenesis. The DNA methyltransferase 1 (DNMT1) protein represents a major DNA methyltransferase activity in human cells and is therefore a prominent target for experimental cancer therapies. However, there are only few available inhibitors and their high toxicity and low specificity have so far precluded their broad use in chemotherapy. Based on the strong conservation of catalytic DNA methyltransferase domains we have used a homology modeling approach to determine the three-dimensional structure of the DNMT1 catalytic domain. Our results suggest an overall structural conservation with other DNA methyltransferases but also indicate local conformational differences. To prove the validity of our model we used it as a template to design a novel derivative of the known DNA methyltransferase inhibitor 5-azacytidine. The resulting compound (N4-fluoroacetyl-5-azacytidine) functioned as an efficient inhibitor of DNA methylation in human tumor cell lines and also provides novel opportunities for pharmacological applications.

Amino Acid Sequence↗

Reliability, validity and factor structure of the GDS-15 in Iranian elderly.

OBJECTIVES: Depressive disorders are a public health problem even in developing countries. Access to valid and reliable screening instruments is needed for conducting community surveys. The main objective of this study is to provide the Iranian version of the Geriatric Depression Scale-15 (GDS). METHODS: The GDS-15 Farsi version was developed by translation and back translation. Two hundred and four subjects aged 59 years or older, who were chosen randomly from residents of the Ekbatan district of Tehran, the capital city of Iran, completed the GDS-15. The Composite International Diagnostic Interview (CIDI) was used to establish a gold standard diagnosis of major depressive disorders. RESULTS: The GDS was found to be an internally consistent measure. Alpha, split-half coefficients and test-retest reliability were 0.9, 0.89 and 0.58 respectively. Two factors were extracted by using factor analysis and the principle component analysis (varimax rotation): 'depression' and 'psychosocial activity'. The Depression factor (omitting items 2, 9, 10, 13), which could be considered as a short form of the scale (alpha = 0.92), has significant correlation with the main scale (r = 0.58). Using receiver operating curve (ROC) analysis, the optimum cutoff score for GDS-15 is 7/8, yielding a sensitivity of 0.9 and a specificity of 0.84. The optimum cutoff score for GDS-11 is 6, yielding a sensitivity of 0.9 and a specificity of 0.83. CONCLUSION: The long and short forms of the GDS have excellent properties as screening instruments for major depression in older dwellers in Iran, particularly in urban areas, as presented in our findings.

Aged↗

The iowa structured psychiatric interview. Rationale, reliability, and validity.

The Iowa Structured Psychiatric Interview (ISPI) is an interview form designed for psychiatric epidemiological research in the general population. Its use provides detailed information about important aspects of psychiatric, social, and family history. Detailed information is gathered about the frequency and duration of symptoms that characterize schizophrenia, mania, depression, and neurosis. The instrument is also designed to be administered by well-trained nonmedical personnel in order to facilitate its utilization in large-scale field studies. Such interviewers are assumed to be blind to the study status of the informants, and the format of the ISPI maintains that blindness throughout crucial sections of the interview. In addition, the ISPI can be used without any implication that the informant or the informant's relatives have any type of psychiatric history or current psychiatric problems. This monograph discusses the rationale for the ISPI and gives a formative history of the instrument. We also present the results of studies investigating the reliability and validity of a set of twenty screening questions for schizophrenia, mania, depression, and neurosis - items which form the nucleus of the ISPI. The excellent reliability of these items is contrasted with the relatively poor reliability of a set of behavior ratings included in the ISPI. The ISPI itself is given in full in an appendix, along with detailed guidelines for use and suggestions for selecting and training personnel to administer the ISPI in the field. We hope that the ISPI can be further tested by other researchers in psychiatric epidemiology.

Adolescent↗

Selecting optimally diverse compounds from structure databases: a validation study of two-dimensional and three-dimensional molecular descriptors.

The efficiency of the drug discovery process can be significantly improved using design techniques to maximize the diversity of structure databases or combinatorial libraries. Here, several physicochemical descriptors were investigated to quantify molecular diversity. Based on the 2D or 3D topological similarity of molecules, the relationship between physicochemical metrics and biological activity was studied to find valid descriptors. Several compounds were selected using those descriptors from a database containing diverse templates and 55 biological classes. It was evaluated whether the obtained subsets represent all biological properties and structural variations of the original database. In addition, hierarchical cluster analyses were used to group molecules from the parent database, which should have similar biological properties. Using various sets of structurally similar molecules, it was possible to derive quantitative measures for compound similarities in relation to biological properties. A similarity radius for 2D fingerprints and molecular steric fields was estimated; compounds within this radius of another molecule were shown to have comparable biological properties. This study demonstrates that 2D fingerprints alone or in combination with other metrics as the primary descriptor allow to handle global diversity. In addition, standard atom-pair descriptors or molecular steric fields can be used to correlate structural diversity with biological activity. Hence, the latter two descriptors can be classified as secondary descriptors useful for analog library design, while 2D fingerprints are applicable to design a general library for lead discovery. Based on these findings, an optimally diverse subset containing only 38% of the entire IC93 database was generated using 2D fingerprints. Here no structure is more similar than 0.85 to any other (Tanimoto coefficient), but all biological classes were selected. This reduction of redundancy led to a child database with the same physicochemical diversity space, which contains the same information as the original database.

Angiotensin-Converting Enzyme Inhibitors↗

Factor structure, reliability, and validity of the Penn State Worry Questionnaire: differences between African-American and White-American college students.

This study examined differences in the factor structure of the Penn State Worry Questionnaire (PSWQ) between African-American (n=181) and White-American (n=180) college students. Results from a confirmatory factor analysis indicated that the traditional single-factor solution did not provide the best fit for the data from either ethnic group. A multiple-group factor analysis indicated that underlying structure of Factor 1 was roughly equivalent between ethnic groups. Structure of Factor 2, however, differed between groups. Specifically, item 10 loaded on different factors for each group. In support of these analyses, an exploratory factor analyses (EFA) among White-American participants indicated the presence of a two-factor model while an EFA among African-Americans indicated the presence of three factors. Despite some overlap in the overall factor structure between ethnic groups, African-Americans scored significantly lower on the PSWQ than the White-American group. Furthermore, among African-Americans level of ethnic identity was negatively related to state and trait measures of anxiety, but unrelated to measures of depression and worry.

Adult↗

Dutch translation of the Fear of Pain Questionnaire: factor structure, reliability and validity.

BACKGROUND: The Fear of Pain Questionnaire (FPQ-III) is a 30-item self-report instrument measuring fear of a variety of pain-related stimuli. AIM: The present study was undertaken to develop a Dutch version of the FPQ-III, to assess the instrument's psychometric qualities, to examine the suggested factor structure, and to relate the FPQ-III to other general psychological constructs in order to assess its construct validity. METHOD: The questionnaire was translated following the forward-backward method. The final version was filled out by (n = 274) psychology freshmen. A random half of the subjects was re-tested after five weeks. RESULTS: Satisfactory psychometric qualities were obtained (average alpha = 0.90 and test-retest reliability = 0.71). Factor analysis supported the three-factor structure and also the results concerning divergent and convergent validity show strong similarity with the results from other studies. CONCLUSIONS: The Dutch translation of the FPQ-III appears to be a valid equivalent of the original English version and does represent a unique construct.

Adolescent↗

The Mini-International Neuropsychiatric Interview (M.I.N.I.): the development and validation of a structured diagnostic psychiatric interview for DSM-IV and ICD-10.

The Mini-International Neuropsychiatric Interview (M.I.N.I.) is a short structured diagnostic interview, developed jointly by psychiatrists and clinicians in the United States and Europe, for DSM-IV and ICD-10 psychiatric disorders. With an administration time of approximately 15 minutes, it was designed to meet the need for a short but accurate structured psychiatric interview for multicenter clinical trials and epidemiology studies and to be used as a first step in outcome tracking in nonresearch clinical settings. The authors describe the development of the M.I.N.I. and its family of interviews: the M.I.N.I.-Screen, the M.I.N.I.-Plus, and the M.I.N.I.-Kid. They report on validation of the M.I.N.I. in relation to the Structured Clinical Interview for DSM-III-R, Patient Version, the Composite International Diagnostic Interview, and expert professional opinion, and they comment on potential applications for this interview.

Adult↗

Data mining of Mycobacterium tuberculosis complex genotyping results using mycobacterial interspersed repetitive units validates the clonal structure of spoligotyping-defined families.

Recently, a combination of spoligotyping and bioinformatics was proposed as a potential tool for defining major circulating clades of tuberculosis bacilli. In the present study, we attempted to validate the above mentioned classification using a new high-throughput marker, named mycobacterial interspersed repetitive units (MIRUs). Using 12 MIRU loci and spoligotyping, we performed data mining of results on clinical isolates of the Mycobacterium tuberculosis complex representative of global mycobacterial allelic diversity. Knowledge rules permitting automatic labeling of major M. tuberculosis families were defined. Using this strategy, MIRU 24 appeared to be most appropriate for classifying our dataset. The Bovis family was shown to be perfectly classified by a maximum of 3 MIRUs, followed by Africanum and East African Indian (EAI) families by 4 MIRUs, the Beijing family by 6 MIRUs, Haarlem and X families by 8 MIRUs, the T family by 9, and the Latin-American and Mediterranean (LAM) family by 10 MIRUs. Considering the hierarchy of family divergence, our results corroborate a recent suggestion that EAI is the ancestral family followed by Africanum and Bovis. On the other hand, T, X, LAM and Haarlem families appear to be of more recent evolution. These results indicate that data mining of MIRUs is a valuable new tool for analyzing the evolutionary dynamics of the M. tuberculosis complex, and for monitoring an infectious disease such as tuberculosis.

Bacterial Typing Techniques↗

Reliability, validity and factor structure of the upper limb subscale of the Motor Assessment Scale (UL-MAS) in adults following stroke.

PURPOSE: The upper limb items of the Motor Assessment Scale (MAS) have been shown to be a sensitive, valid and reliable measure of upper limb function for adults following stroke, however the validity and reliability of summing these items into an independent subscale has not yet been evaluated. The stability, internal consistency and construct validity of the upper limb MAS subscale (UL-MAS) was assessed in this study. METHOD: Twenty-seven inpatients following stroke (mean age = 67 years, range = 40 - 80) were sampled from an acute, inpatient rehabilitation setting. Patients were evaluated with 'Upper Arm Function', 'Hand Movements', and 'Advanced Hand Activities' items of the MAS by masked physiotherapists who had received standardized training in administration of the MAS. RESULTS: All items were explained by one factor on confirmatory factor analysis and correlated significantly with one another and with the composite (summed total) score. Internal consistency analysis produced a Cronbach's alpha of 0.83 which did not benefit from removal of any items. CONCLUSIONS: The acceptable internal consistency score obtained verifies the validity and reliability of using the UL-MAS as an independent scale. This study has also verified the construct validity of the UL-MAS subscale and provides a valuable extension of previous work, which together demonstrates the value of the UL-MAS as a responsive, valid and reliable measure of upper limb function in adults following stroke. The UL-MAS produced a single, composite score that could be interpreted as a total score for upper limb function in this population.

Adult↗

An expanded childhood anxiety sensitivity index: its factor structure, reliability, and validity in a non-clinical adolescent sample.

Anxiety sensitivity refers to the fear of anxiety-related bodily sensations that are interpreted as having potentially harmful somatic, psychological, or social consequences. The current study examined the factor analytic structure of anxiety sensitivity in a large sample of normal adolescents (N=518) using the revised childhood anxiety sensitivity index (CASI-R). Confirmatory factor analysis indicated that anxiety sensitivity as measured by the CASI-R can best be conceptualised as a hierarchical construct with four lower-order factors loading on a single higher-order factor. The lower-order factors were 'fear of cardiovascular symptoms', 'fear of publicly observable anxiety reactions', 'fear of cognitive dyscontrol', and 'fear of respiratory symptoms'. An additional aim of the present study was to investigate the psychometric properties of the CASI-R. Results showed the CASI-R to be a reliable scale in terms of internal consistency. Furthermore, CASI-R scores were substantially related to levels of anxiety sensitivity as measured by the original index, trait anxiety, symptoms of anxiety disorders, in particular 'panic disorder and agoraphobia', and depression. Finally, some evidence was found for the validity of the CASI-R factor scores. That is, all factors convincingly loaded on symptoms of 'panic disorder and agoraphobia', whereas the factor 'fear of publicly observable anxiety reactions' was also strongly associated with symptoms of 'social phobia'.

Adolescent↗

Summer mood in winter depressives: validation of a structured interview.

Two structured interviews, the Hypomania Interview Guide (Including Hyperthymia), for Seasonal Affective Disorder (HIGH-SAD) and its successor, the Hypomania Interview Guide (Including Hyperthymia), Retrospective Assessment Version (HIGH-R), were validated for the assessment of nondepressed spring/summer mood states in patients with DSM-III-R or DSM-IV diagnoses of Recurrent Bipolar disorder (I, II or NOS) or Recurrent Major Depressive Disorder (MDD; unipolar), both with Seasonal Pattern, and in normal control subjects (HIGH-SAD only). The instruments retrospectively rate the frequency and severity of DSM diagnostic criterion features as well as several non-DSM features. Both instruments had high internal consistency. Normal controls had lower total scores than unipolar patients, who had lower scores than bipolar patients. Total score classified 85-91% of patients with seasonal affective disorder (SAD) into the correct unipolar or bipolar group. For boundary mood cases, small subsets of features provided better classification accuracy. Based on total score, MDD patients were divided into three subgroups: euthymes (normal mood), hyperthymes (slightly elevated mood), and high-hyperthymes (scores overlapping with hypomania). With the exception of sharpened thinking, DSM items dominated patient classifications. Distinct clusters of "positive" (pleasant, agreeable) or "negative" (impairing) features described the mood states. The HIGH-R and HIGH-SAD are useful for discriminating and classifying hypomania and mania in bipolar patients, and euthymia and hyperthymia in unipolar patients.

Adolescent↗

Factor structure and predictive validity of the Obsessive Compulsive Drinking Scale.

BACKGROUND: The Obsessive Compulsive Drinking Scale (OCDS) is a 14-item, self-report instrument developed to measure obsessive thoughts about alcohol use and compulsive behaviors toward drinking. The objective of this study was to ascertain the factor structure underlying responses to the OCDS, and to further assess whether subscale scores derived from this structure were distinctive, internally consistent, predictive of future drinking, and able to differentiate between patients receiving naltrexone versus placebo in a controlled alcoholism treatment trial. METHODS: OCDS data were collected from a total of 132 alcohol-dependent subjects at up to 15 assessment points during the study. Interitem correlations were pooled across assessment periods, and an iterated principal axis factor analysis with oblique promax rotation was performed. The factor analysis suggested that three primary factors could parsimoniously account for the common variance in item responses. Subscale scores were formed by summing responses to the most salient items on each factor. RESULTS: The three common factors were interpreted as "resistance/control impairment," "obsession," and "interference." The subscale scores corresponding to these three factors were internally consistent, and their correlation with other baseline measures of alcohol use and severity suggested that they were distinct. Scores on each subscale reliably distinguished between subjects who remained abstinent, exhibited "slip" drinking, or relapsed to heavy drinking during the 12 weeks of active treatment. Additionally, scores on the resistance/control impairment subscale distinguished between those patients receiving treatment with naltrexone or placebo. Scores from each subscale also were able to predict the hazard for heavy drinking in the following week of treatment. CONCLUSIONS: The three OCDS factors are easily estimated with the summated scoring approach, and the resulting subscales appear to be internally consistent and distinctive. Moreover, the group differentiation capability and predictive utility of the subscale scores suggest that they might be useful as either predictor or outcome variables in alcoholism treatment trials. The duration of time for which a given OCDS assessment maintains its predictive utility awaits further confirmation.

Adult↗

Validity of a structured method of selecting abstracts for a plastic surgical scientific meeting.

In 1999, the European Association of Plastic Surgeons accepted a structured method to assess and select the abstracts that are submitted for its yearly scientific meeting. The two criteria used to evaluate whether such a selection method is accurate were reliability and validity. The authors previously established this method to be reliable on the basis of a prospective evaluation of the selection process used for the 2000 meeting of the European Association of Plastic Surgeons. It is more difficult to assess the validity of this method because there is no objective standard of quality of a scientific abstract against which the accuracy of selection can be assessed. This study statistically evaluated the accuracy of the meeting participants' assessment of presentations made during the meeting as the criterion standard for abstract selection on the basis of data obtained from the 2002 selection process. The authors evaluated the interobserver repeatability among five meeting participants of selecting the best presentations, the validity of the method of abstract selection after this criterion standard had been established, and the validity of reviewers' rating of abstracts as indicators of the scientific value of the actual presentations. The authors conclude that the assessment of platform presentations at a plastic surgical meeting is reliable. Accepting this assessment as the criterion standard, however, they could not prove the validity of their selection method or the validity of the reviewers' rating of abstracts as an indicator of the scientific value of the actual presentations.

Abstracting and Indexing↗

The factor structure and criterion validity of the short form of the Eating Attitudes Test.

One of the more frequently used measures of eating disorders is the 40-item Eating Attitudes Test (EAT) developed by Garner and Garfinkel (1979). Although originally designed to diagnose anorexia nervosa, the test has recently been applied to nonclinical populations also. In this study, we examined psychometric and validity data for a short version of the scale, the EAT-26. Using a sample of 809 female soldiers in their late teens, results showed that the EAT-26 is reliable, the factor structure is different from that obtained in clinical groups, and the EAT-26 is significantly correlated with body image, weight, and diet.

Adolescent↗