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PubMed2003

The development and validation of a knowledge, attitude and behaviour questionnaire to assess undergraduate evidence-based practice teaching and learning.

OBJECTIVES: Most evidence-based practice (EBP) educational assessment tools evaluated to date have focused on specific knowledge components or technical skills. Other important potential barriers to the adoption of EBP, such as attitudinal, perceptual and behavioural factors, have yet to be studied, especially in the undergraduate setting. Therefore, we developed and validated a knowledge, attitude and behaviour questionnaire designed to evaluate EBP teaching and learning in an undergraduate medical curriculum. METHODS: We derived the questionnaire from a comprehensive literature review, informed by international and local experts and a Year 5 student focus group. We determined its factor structure and refined and validated the questionnaire according to the responses of a cohort of Year 5 and a combined group of Years 2 and 3 students using principal components factor analysis with varimax rotation. Factor reliability was computed using Cronbach's alpha coefficient. We assessed construct validity by correlating the factors with other measures of EBP activity and examined responsiveness through paired t-test of the pre/post factor mean scores. RESULTS: A 43-item questionnaire was developed. Four factors were identified from both student groups. The overall questionnaire as well as each factor had high construct validity (Cronbach's alpha > 0.7 for each scale). No significant correlations were found between the 4 factors, confirming their orthogonality. Positive correlations, however, resulted between factor mean scores and other EBP activities. The responsiveness of the questionnaire was satisfactory. CONCLUSION: A reliable knowledge, attitude and behaviour measure of EBP teaching and learning appropriate for undergraduate medical education has been developed and validated.

Adult↗
PubMed2005

[The assessment of obsessive-compulsive symptoms: the reliability and validity of the Padua inventory in a Turkish population].

OBJECTIVE: We examined the reliability and validity of the 60-and 41-item versions of the Padua Inventory (PI and PI-R) which were developed to assess the frequency and severity of obsessive-compulsive symptoms, in a Turkish population. METHOD: The sample consisted of 43 OCD patients, 30 non-OCD patients with other anxiety disorders, 30 nonobsessional depressed patients, 76 healthy adults, and 181 undergraduate students. We investigated internal consistency, test-retest reliability, and factor structure, concurrent and discriminant validity. RESULTS: Psychometric analyses showed that both the original PI and PI-R had a high internal consistency and test-retest reliability. While principal factor analysis of the 41 items revealed six factors that are consistent with the PI-R, the factor structure of the original scale was not confirmed. All the subcales and total scores for both instruments were significantly correlated with the Yale-Brown scores except for the impulses subscale. There were significant differences between OCD patients and nonclinical samples in all total and subscale scores for both instruments. OCD patients scored significantly higher on the total, contamination/washing and checking subscales for both instruments than nonobsessional anxious, and depressed patients. While OCD patients scored significantly higher on the PI-R rumination scale than nonobsessional anxious patients, their PI impaired control subscale score was not different from that of the other clinical groups. CONCLUSIONS: The Turkish version of the PI has appropriate reliability and validity for assessing the frequency and severity of obsessive-compulsive symptoms.

Adolescent↗
PubMed2005

The validity of the Parental Bonding Instrument as a measure of maternal bonding among young Pakistani women.

BACKGROUND: Parenting may have an important influence upon women's mental health in societies characterized by strong male gender preference. The Parental Bonding Interview (PBI) has been very widely used, but not yet formally evaluated in a South Asian context. The purpose of this pilot study was to assess the factor structure, face and concurrent validity of the PBI as an assessment of maternal bonding among young Pakistani women. METHODS: A total of 86 women, aged 20-35 years, were identified by door-knocking in two small catchment areas in Islamabad/Rawalpindi, one characterized by higher and one by lower socio-economic status. The PBI, the Clinical Interview Schedule Revised (CIS-R) and the Marital Satisfaction Scale (MSS) were each administered by a female interviewer in the respondent's home. RESULTS: All women agreed to be interviewed privately, the response rate was 100%. Consistent with previous reports, PBI items loaded on two well-characterized internally consistent scales, care and overprotection. In a three-factor solution, the overprotection scale divided into two subscales previously characterized as "Encouragement of Behavioral Freedom" and "Denial of Psychological Autonomy". Concurrent validity was supported by correlations in the expected direction between PBI care and overprotection subscales and both psychological morbidity (CIS-R) and marital satisfaction (MSS). CONCLUSIONS: Pakistani women seem to perceive and respond to PBI items as addressing parental "control" or "overprotection" in a similar similar way to respondents from western Anglophone cultures. This study provides further support for the core construct validity of the PBI, and indicates a perhaps surprising degree of sensitivity to cultural nuances.

Adult↗
PubMed2003

Development and testing of the pain opioid analgesics beliefs scale in Taiwanese cancer patients.

The purpose of the study was to develop and preliminarily test the feasibility, validity, reliability, and factor structures of the Pain Opioid Analgesics Beliefs Scale-Cancer (POABS-CA) in hospitalized adults diagnosed with cancer in Taiwan. This scale was developed in three phases. In Phase I, item development was based on qualitative analysis as well as a review of the literature. Face validity, content validity, and feasibility were also evaluated. In Phase II, internal consistency reliability was further tested in 42 subjects with pain. In Phase III, test-retest reliability, internal consistency, and essential construct validity were further assessed in a sample of 361 hospitalized cancer patients with pain. The POABS-CA evolved from testing as a 10-item 5-point Likert-type instrument. Higher scores indicated more negative beliefs regarding opioids and their use in managing pain. Satisfactory face validity and content validity were found. The POABS-CA was also shown to be a reliable and stable pain belief scale, with Cronbach's alpha and test-retest reliability of 0.70 and 0.94, respectively. Two factors, namely pain endurance beliefs and negative effect beliefs, were extracted from the principal component factor analysis to support the construct validity. In conclusion, preliminary evidence indicates the POABS-CA is a reliable, stable, valid and easily applied scale for assessing beliefs regarding opioid use for cancer pain. Further studies should test this scale in different populations to increase its applications in cancer pain management.

Adult↗
PubMed2002

[Validation of a self-administered functional evaluation questionnaire after surgical treatment of lumbar spine stenosis].

PURPOSE OF THE STUDY: The main aim of this prospective, multicentric, observational study was to validate a self-administered quality-of-life questionnaire for patients with lumbar spine stenosis treated surgically. MATERIAL AND METHODS: The self-administered questionnaire was composed of eight questions exploring three dimensions: lumbalgia, radiculalgia, radicular ischemia. This questionnaire was associated with an index of neurological involvement (to take into account objective neurological data), and with an index of patient satisfaction (to assess the patient's perception of the impact of surgery on lumbalgia, radiculalgia, and gait disorders). The scoring scale was validated by studying the structure of the questionnaire (to ascertain the pertinence of the proposed three dimensions), by determining the questionnaire's reproducibility (intraobserver variability) and sensitivity to change, and by examining the contents of the questions (to assess the capacity of the scale to effectively measure the parameters it was designed to measure). Cronbach's alpha coefficient and principal component analysis were used to assess the questionnaire's structure. Reproducibility was tested on 49 patients who completed the self-administered questionnaire twice at a 15-day interval; intraclass correlation coefficients were determined. Sensibility was tested by correlating variation in the scores obtained pre- and postoperatively with the index of satisfaction; mean standard responses were determined. The validity of the questionnaire's content was assessed by correlating the scores obtained with the questionnaire to those obtained with three other self-administered questionnaires: SF36, EIFEL2 and GHA38. RESULTS: This work included 104 patients, 96 of whom were reviewed at consultations 6 and 12 months after surgery. The principal components analysis confirmed the presence of the three dimensions. The global Cronbach alpha coefficient was 0.86. The global intraclass coefficient of correlation was 0.95, varying from 0.86 to 0.97 depending on the dimension studied. There was a good correlation (0.82) between changes in the score studied and the index of satisfaction. All the mean standardized responses were higher than 1, indicating good sensitivity to change. There was also a good correlation between the questionnaire tested and the EIFEL2 self-administered questionnaire and the following dimensions of the SF36: physical activity, physical pain, vitality, and limitation due to physical pain. DISCUSSION AND CONCLUSION: Associating a simple 8-question self-administered questionnaire with an index of satisfaction (4 questions) and an objective index of neurological involvement provided a reliable, sensitive, and reproducible assessment of the changes in functional disorders resulting from lumber stenosis before and after surgical treatment.

Activities of Daily Living↗
PubMed2004

Crystal structure of human thymidine phosphorylase in complex with a small molecule inhibitor.

Human thymidine phosphorylase (HTP), also known as platelet-derived endothelial cell growth factor (PD-ECGF), is overexpressed in certain solid tumors where it is linked to poor prognosis. HTP expression is utilized for certain chemotherapeutic strategies and is also thought to play a role in tumor angiogenesis. We determined the structure of HTP bound to the small molecule inhibitor 5-chloro-6-[1-(2-iminopyrrolidinyl) methyl] uracil hydrochloride (TPI). The inhibitor appears to mimic the substrate transition state, which may help explain the potency of this inhibitor and the catalytic mechanism of pyrimidine nucleotide phosphorylases (PYNPs). Further, we have confirmed the validity of the HTP structure as a template for structure-based drug design by predicting binding affinities for TPI and other known HTP inhibitors using in silico docking techniques. This work provides the first structural insight into the binding mode of any inhibitor to this important drug target and forms the basis for designing novel inhibitors for use in anticancer therapy.

Crystallization↗
PubMed1993

Selecting anaesthetists: the use of psychological tests and structured interviews.

To test the predictive validity of a selection system for Senior House Officers (SHOs) and registrars in anaesthetics, 140 doctors short-listed from 635 applications between 1980 and 1987 were assessed by a semi-structured interview assessed and a personality questionnaire (Cattell 16PFQ-form C). The 62 doctors selected were followed up for between 3 and 8 years. Future performance was predicted from the psychological tests and by the interviewers. Academic, clinical, behavioural, and overall performance were used as criteria of outcome. Correlation coefficients between prediction and outcome measures were statistically highly significant (P < 0.01). Using multiple regression, equations could be derived from five of the Cattell personality factors to predict overall performance. Personality measures discriminated significantly between the best and poorest performers. Interview predictions were also statistically significant (P < 0.01). The method provides a blueprint for the effective selection of junior anaesthetists. Wastage in terms of those leaving the specialty was 16%.

Anesthesiology↗
PubMed2003

Benzoxazine oligomers: evidence for a helical structure from solid-state NMR spectroscopy and DFT-based dynamics and chemical shift calculations.

A combination of molecular modeling, DFT calculations, and advanced solid-state NMR experiments is used to elucidate the supramolecular structure of a series of benzoxazine oligomers. Intramolecular hydrogen bonds are characterized and identified as the driving forces for ring-shape and helical conformations of trimeric and tetrameric units. In fast MAS (1)H NMR spectra, the resonances of the protons forming the hydrogen bonds can be assigned and used for validating and refining the structure by means of DFT-based geometry optimizations and (1)H chemical-shift calculations. Also supporting these proposed structures are homonuclear (1)H[bond](1)H double-quantum NMR spectra, which identify the local proton-proton proximities in each material. Additionally, quantitative (15)N[bond](1)H distance measurements obtained by analysis of dipolar spinning sideband patterns confirm the optimized geometry of the tetramer. These results clearly support the predicted helical geometry of the benzoxazine polymer. This geometry, in which the N...H...O and O...H...O hydrogen bonds are protected on the inside of the helix, can account for many of the exemplary chemical properties of the polybenzoxazine materials. The combination of advanced experimental solid-state NMR spectroscopy with computational geometry optimizations, total energy, and NMR spectra calculations is a powerful tool for structural analysis. Its results provide significantly more confidence than the individual measurements or calculations alone, in particular, because the microscopic structure of many disordered systems cannot be elucidated by means of conventional methods due to lack of long-range order.

Journal Article↗
PubMed2001

[Factoral structure and psychometric properties of the German version of the Toronto Alexithymia Scale (TAS-20) in psychosomatic patients].

The present paper describes the attempt to cross-validate the three-factorial structure of the German Version of the 20-Item Toronto Alexithymia Scale in a population of 419 patients, suffering of psychogenic disorders. However, results neither revealed good internal consistencies nor was it possible to obtain an acceptable adaptation of the empirical data on the postulated model. Therefore an explorative factor analysis was performed in order to get a more consistent factor model. The hereby resulting four-factorial structure was congruent with reference to theoretical and empirical data of Alexithymia. However, additional cross-validation in other populations has to be investigated.

Adult↗
PubMed1996

Spectral characterization of fluconazole.

Reference 1H, 19F and 13C NMR, mass, IR and Raman spectra are provided to the open literature for the first time for the potent antifungal agent fluconazole, alpha-(2,4-difluorophenyl)-alpha-(1H-1,2,4-triazol-1-ylmethyl++ +)-1H-1,2, 4-triazole-1-ethanol. The 1H, 19F and 13C NMR spectra were analyzed in detail to attribute shifts, including 19F chemical shifts and C-F and F-F coupling constants. The EI mass spectrum, although rich in fragment ions, lacked a molecular ion. FAB and MS/MS experiments were undertaken in support of the structure in order to validate the EI spectrum as a reference mass spectrum. IR and Raman spectra are compared to show the complementary nature of their features and discussed in terms of principal group vibrations. NMR and vibrational data together with assignments are summarized in tabulated form for convenience of use. All these data are consistent with the structure of fluconazole.

Antifungal Agents↗
PubMed2003

Biochemical filtering of a protein-protein docking simulation identifies the structure of a complex between a recombinant antibody fragment and alpha-bungarotoxin.

The structural characterization of a complex of alpha-bungarotoxin with a recombinant antibody fragment that mimics the acetylcholine receptor was achieved using docking simulation procedures. To drive the computer simulation towards a limited set of solutions with biological significance, a filter, incorporating general considerations of antigen-antibody interactions, specificity of the selected antibody fragment and results from alpha-bungarotoxin epitope mapping, was adopted. Two similar structures were obtained for the complex, both of them stabilized by cation-pi and hydrophobic interactions due to tyrosilyl residues of the antibody fragment. Site-directed mutagenesis studies, removing each of the latter aromatic residues and causing full inactivation of the interaction process between the antibody fragment and the neurotoxin, support the validity of the calculated structure of the complex.

Amino Acid Sequence↗
PubMedDate not supplied

Innovations in bayes and empirical bayes methods: estimating parameters, populations and ranks.

By formalizing the relation among components and 'borrowing information' among them, Bayes and empirical Bayes methods can produce more valid, efficient and informative statistical evaluations than those based on traditional methods. In addition, Bayesian structuring of complicated models and goals guides development of appropriate statistical approaches and generates summaries which properly account for sampling and modelling uncertainty. Computing innovations enable implementation of complex and relevant models, thereby substantially increasing the role of Bayes/empirical Bayes methods in important statistical assessments. Policy-relevant statistical assessments involve synthesis of information from a set of related components such as medical clinics, geographic regions or research studies. Typical assessments include inference for individual parameters, synthesis over the collection of components (for example, the parameter histogram) and comparisons among parameters (for example, ranks). The relative importance of these goals depends on the context. Bayesian structuring provides a guide to valid inference. For example, while posterior means are the 'obvious' and optimal estimates for individual components under squared error loss, their empirical distribution function (EDF) is underdispersed and never valid for estimating the EDF of the true, underlying parameters. Effective histogram estimates result from optimizing a loss function based in a distance between the histogram and its estimate. Similarly, ranking observed data usually produces poor estimates and ranking posterior means can be inappropriate. Effective estimates should be based on a loss function that caters directly to ranks. Using examples of 'borrowing information', shrinkage and the variance/bias trade-off we motivate Bayes and empirical Bayes analysis. Then, we outline the formal approach and discuss 'triple-goal' estimates with values that when ranked produce optimal ranks, for which the EDF is an optimal estimate of the parameter EDF and such that the values themselves are effective estimates of co-ordinate-specific parameters. We use basic models and data analysis examples to highlight the conceptual and structural issues.

Animals↗
PubMed2006

Structure of high-performance evaporators for space application.

A new structure of cold plates, where an unheated auxiliary channel is installed to supply liquid directly to the bottom of coalesced flattened bubbles in a narrow heated channel, is tested to investigate the increase in critical heat flux. Assuming the application to the laser solar power system, a large heating surface with a length of 150 mm in the flow direction is employed, and a narrow channel structure is adopted to reduce the size of cold plates, where the gap sizes are selected as 5 mm and 2 mm. Experiments are performed for water as a test liquid at inlet subcooling of 15 K under near atmospheric pressure. Inlet liquid velocity is varied from 0.065 m/s to 0.6m/s for the upward flow on ground. A value of critical heat flux of 2.2 x 10(6) W/m2 is obtained for 5-mm gap size at the inlet velocity of 0.2 m/s. At low liquid flow rate, the structure realizes the CHF values larger by 2.5 times than those for the normal heated channel without additional liquid supply. A new method to evaluate the performance of cold plates is proposed to take account of the variation in the size of heating surface, inlet liquid velocity, and subcooling that influence the CHF values. The validity of the proposed structure of the cold plate for the increase in critical heat flux is confirmed.

Journal Article↗
PubMed2000

Measuring cluster similarity across methods.

Cluster analysis techniques delineate groupings or categories of observations based on some shared commonality over a set of variables. If such groupings can be formed, their commonality may be investigated to define relationships that may otherwise go undetected given their complexity. However, the cluster analyses are inappropriate unless the results can be replicated. A number of clustering techniques are available, differing mostly in the technical criteria used to judge the similarity of the observations. There is added validity to the cluster structure when different methods produce similar groupings; however, in most cases, different clustering techniques will not produce identical clusters and the extent of cluster similarity becomes an important measure. In this paper the hypergeometric distribution is used to gauge cluster similarity across different methods, providing an appropriate measure of consistency. This measure is used to validate reproducibility of the clusters.

Cluster Analysis↗
PubMed2003

Development and validation of the hyperlipidemia: attitudes and beliefs in treatment (HABIT) survey for physicians.

INTRODUCTION: Many patients treated with lipid-lowering medications in clinical practice do not achieve targeted National Cholesterol Education Program (NCEP) goals for low-density lipoprotein cholesterol (LDL-C), despite the proven efficacy of these medications. Understanding physician attitudes and beliefs about treating patients to goal may be useful in improving patient care and ensuring that all patients receive the benefits of treatments shown to be optimal in clinical trials. OBJECTIVE: To develop a theoretically based, and statistically reliable and valid survey instrument for measuring the attitudes and beliefs of physicians toward hyperlipidemia and its treatment, including treatment of patients to goal. To determine whether the attitudes measured were associated with physician intentions to treat patients to LDL-C goal. METHODS: We assessed the reliability of the instrument through an examination of the internal consistency and factor structure of the constructs. Validity was assessed through zero-order correlations among the constructs and the relationship between the constructs and an intent to treat to goal case study. RESULTS: Internal consistency scores for the 8 constructs ranged from 0.48 to 0.75. Factor loadings indicated that the individual items belonged to their respective constructs, as hypothesized. The predictive validity of the instrument was demonstrated by significant relationships between 5 of the 8 attitudinal constructs and an intent to treat to goal case study. CONCLUSIONS: The HABIT physician survey is the first validated instrument covering a broad set of attitudes about the treatment of hyperlipidemia that are both theoretically and empirically linked to physician intent to treat to NCEP LDL-C goal.

Attitude of Health Personnel↗
PubMed2003

Translation and validation of a French version of Brown's Support Behaviors Inventory in perinatal health.

This article describes the process used for translation, testing for reliability and validity, and establishing factor structure of a French version of Brown's Support Behaviors Inventory (SBI-Fr). The objective was to provide an adequate self-report measure of satisfaction with social support during the perinatal period for use with a Francophone population in Québec, Canada. When compared with the English version, the French version had similar qualities regarding reliability and validity, but principal component analysis (N = 271) revealed that the SBI-Fr measures two distinct subscales, perceived satisfaction with partner's and others' support. The availability of the SBI-Fr will facilitate the inclusion of Francophone respondents in studies of satisfaction with social support during the perinatal period and permit cross-cultural comparison between Francophone and other populations in not only Canada but also other French-speaking countries.

Abortion, Spontaneous↗
PubMed1998

Analysis of error propagation from NMR-derived internuclear distances into molecular structure of cyclo-pro-gly.

Analytical expressions have been derived that translate uncertainties in distance constraints (obtained from NMR investigations) into uncertainties in atom positions in the maximum likelihood (ML) structure consistent with these inputs. As a test of this approach, a comparison was made between test structures reconstructed by the new ML approach, which yields a single structure and a covariance matrix for coordinates, and those reconstructed by metric matrix distance-geometry (MMDG), which yields a family of structures that sample uncertainty space. The test structures used were 560 polyhedra, with edges of arbitrary length containing up to 50 vertices, and one polyhedron, with 100 vertices; randomized distance constraints generated from these structures were used in reconstructing the polyhedra. The uncertainties derived from the two methods showed excellent agreement, and the correlation improved, as expected, with increasingly larger numbers of MMDG structures. This agreement supports the validity of the rapid analytical ML approach, which requires the calculation of only a single structure. As a second test of the ML method, the approach was applied to the determination of uncertainties in the structure of a cyclic dipeptide, cyclo(DL-Pro-Gly) (cPG), derived from NMR cross-relaxation data. The input data were interproton distances calculated from NOEs measured for a solution of the peptide in 2:1 DMSO:H2O at -40 degreesC (so as to yield large negative NOEs). In order to evaluate effects of the quality of the input spectral parameters on the precision of the resulting NMR structure, information from the covalent geometry of cPG was not used in the structure calculations. Results obtained from the analytical ML approach compared favorably with those from the much slower random-walk variant of the Monte Carlo method applied to the same input data. As a third test, the ML approach was used with synthetic structural constraints for a small protein; the results indicate that it will be feasible to use this rapid method to translate uncertainties associated with a given set of distance restraints into uncertainties in atom positions in larger molecules.

Dipeptides↗
PubMed2005

Cross-cultural adaptation and validation of the Brazilian Portuguese version of the short musculoskeletal function assessment questionnaire: the SMFA-BR.

BACKGROUND: This study was designed to translate, culturally adapt, and validate a Brazilian Portuguese version of the Short Musculoskeletal Function Assessment Questionnaire (SMFA-BR). METHODS: The SMFA was translated from English into Brazilian Portuguese. Translations were synthesized, translated back into English, and then submitted to a committee of clinical, psychometric, and language experts. The questionnaire was then administered to 220 trauma patients at a midsize hospital in southern Brazil. Test-retest reliability was examined at one and seven days. Scale reliability and validity were assessed, and factor structure was analyzed. RESULTS: Patients with only one region of dysfunction reported less dysfunction than did patients with two or three regions of dysfunction. Both the SMFA-BR dysfunction and the SMFA-BR bother scores had significant correlations with all Brazilian Short Form-36 (SF-36) subscales except for bodily pain. Test-retest reliabilities, as determined by intraclass correlation analyses, were 0.99 (95% confidence interval, 0.97, 1.00) at one day (n = 10) and 0.99 (95% confidence interval, 0.96, 1.00) at seven days (n = 17) for the dysfunction index and 0.99 (95% confidence interval, 0.98, 1.00) at one day (n = 10) and 0.97 (95% confidence interval, 0.97, 1.00) at seven days (n = 17) for the bother index. Cronbach alpha reliabilities were 0.95 (95% confidence interval, 0.93, 0.97) and 0.91 (95% confidence interval, 0.89, 0.94) for the dysfunction and bother indices, respectively. Minimal ceiling and floor effects were observed for the bother subscale only. Exploratory factor analysis yielded a three-factor structure: upper-extremity dysfunction, lower-extremity dysfunction, and bother. CONCLUSIONS: A reliable and valid Brazilian Portuguese version of the SMFA was developed. It will facilitate the examination of functional performance within a large patient population as well as allow cross-cultural comparisons.

Adolescent↗