Validation of an experimental polyurethane model for biomechanical studies on implant supported prosthesis - tension tests

OBJECTIVES: The complexity and heterogeneity of human bone, as well as ethical issues, frequently hinder the development of clinical trials. The purpose of this in vitro study was to determine the modulus of elasticity of a polyurethane isotropic experimental model via tension tests, comparing the results to those reported in the literature for mandibular bone, in order to validate the use of such a model in lieu of mandibular bone in biomechanical studies. MATERIAL AND METHODS: Forty-five polyurethane test specimens were divided into 3 groups of 15 specimens each, according to the ratio (A/B) of polyurethane reagents (PU-1: 1/0.5, PU-2: 1/1, PU-3: 1/1.5). RESULTS: Tension tests were performed in each experimental group and the modulus of elasticity values found were 192.98 MPa (SD=57.20) for PU-1, 347.90 MPa (SD=109.54) for PU-2 and 304.64 MPa (SD=25.48) for PU-3. CONCLUSION: The concentration of choice for building the experimental model was 1/1.

Validation of an experimental polyurethane model for biomechanical studies on implant-supported prosthesis: compression tests

OBJECTIVES: The complexity and heterogeneity of human bone, as well as ethical issues, most always hinder the performance of clinical trials. Thus, in vitro studies become an important source of information for the understanding of biomechanical events on implant-supported prostheses, although study results cannot be considered reliable unless validation studies are conducted. The purpose of this work was to validate an artificial experimental model based on its modulus of elasticity, to simulate the performance of human bone in vivo in biomechanical studies of implant-supported prostheses. MATERIAL AND METHODS: In this study, fast-curing polyurethane (F16 polyurethane, Axson) was used to build 40 specimens that were divided into five groups. The following reagent ratios (part A/part B) were used: Group A (0.5/1.0), Group B (0.8/1.0), Group C (1.0/1.0), Group D (1.2/1.0), and Group E (1.5/1.0). A universal testing machine (Kratos model K - 2000 MP) was used to measure modulus of elasticity values by compression. RESULTS: Mean modulus of elasticity values were: Group A - 389.72 MPa, Group B - 529.19 MPa, Group C - 571.11 MPa, Group D - 470.35 MPa, Group E - 437.36 MPa. CONCLUSION: The best mechanical characteristics and modulus of elasticity value comparable to that of human trabecular bone were obtained when A/B ratio was 1:1.

Cross-cultural adaptation, validation and reliability of the Body Area Scale for Brazilian adolescents

The aim of this study was to translate, validate and verify the reliability of the Body Area Scale (BAS). Participants were 386 teenagers, enrolled in a private school. Translation into Portuguese was conducted. The instrument was evaluated for internal consistency and construct validation analysis. Reproducibility was evaluated using the Wilcoxon test and the coefficient of interclass correlation. The BAS demonstrated good values for internal consistency (0.90 and 0.88) and was able to discriminate boys and girls according to nutritional state (p = 0.020 and p = 0.026, respectively). BAS scores correlated with adolescents' BMI (r = 0.14, p = 0.055; r = 0.23, p = 0.001) and WC (r =0.13, p = 0.083; r = 0.22, 0.002). Reliability was confirmed by the coefficient of inter-class correlation (0.35, p < 0.001; 0.60, p < 0.001) for boys and girls, respectively. The instrument performed well in terms of understanding and time of completion. BAS was successfully translated into Portuguese and presented good validity when applied to adolescents.

Validation of a food frequency questionnaire to assess the consumption of carotenoids, fruits and vegetables among adolescents: the method of triads

The aim of this study was to validate the intake of carotenoids, fruits and vegetables estimated by the Food Frequency Questionnaire for Adolescents (FFQA) using the method of triads. Blood samples were collected from 80 elementary school adolescents to assess serum levels of β-carotene. Partial correlation coefficients (r) were calculated between an estimated intake of carotenoids, fruits and vegetables and the serum levels of β-carotene. Validity coefficients were calculated using the method of triads. With the exception of carotenoids, partial r from the food frequency questionnaire (FFQ) were greater than those of the 24-hour recall (24hR). The fruit/vegetable group showed the highest partial r for the FFQ (r = 0.235) and the 24hR (r = 0.137). The highest validity coefficient was obtained for the vegetable group, as assessed by the FFQ (r = 0.873). On average, the validity coefficient values for the FFQ were greater than those obtained for the 24hR or the β-carotene serum levels. The FFQA is an accurate tool for estimating the intake of carotenoids, fruits and vegetables in this population group.

Validation of brief pain inventory to Brazilian patients with pain

To validate the Brazilian version of the Brief Pain Inventory (BPI-B) scale and to determine the optimal cutpoints for mild, moderate, and severe pain based on patients` rating of their worst pain. One hundred forty-three outpatients with cancer were recruited in Hospital das Clinicas-University of Sao Paulo, Brazil. Confirmatory factor analysis confirmed two underlying dimensions, pain severity, and pain interference, with Cronbach`s alpha of 0.91 and 0.87, respectively. Convergent validity was shown by the correlation observed between the BPI dimensions with the EORTC-QLQ-C30 pain scale and the McGill Pain Questionnaire. The BPI-B detected significant differences in the two dimensions by disease and performance status, supporting known-group validity. For the worst pain, the optimal cutpoints were 4 and 7 (1-4 = mild pain, 5-7 = moderate, and 8-10 = severe). Our data show that BPI-B is a brief, useful, and valid tool for assessing pain and its impact on patient`s life.

Cross-cultural adaptation and validation of a Quality of Life questionnaire: The Nasal Obstruction Symptom Evaluation questionnaire

Background:The Nasal Obstruction Symptom Evaluation (NOSE) instrument is a disease-specific questionnaire for assessing the outcome of an intervention in nasal obstruction in trials. This instrument is only available in the English language and cross-culturally valid questionnaires are very important for all research, including nasal obstruction. The aim of the current study was to reproduce the cross-cultural adaptation process for the NOSE questionnaire in the Portuguese language (NOSE-p). Methodology: Cross-cultural adaptation and validation of the instrument were divided into two stages. Stage I involved four bilingual professionals, an expert committee and the author of the original instrument. In Stage 2, the NOSE-p was tested on 33 patients undergoing septoplasty for internal consistency, test-retest reliability, construct validity. discriminant validity, criterion validity, and response sensitivity. Results: The cross-cultural adaptation process was completed and the NOSE-p was demonstrated to be a valid instrument with satisfactory construct validity. It showed an adequate internal consistency reliability and adequate test-retest reliability. It could discriminate between patients with and without nasal obstruction and it has a high response sensitivity to change. Conclusions: The cross-cultural adaptation and validation process demonstrated to be valid and the NOSE-p proved to be applicable in Brazil.

Cross-cultural adaptation and validation of a Brazilian Portuguese version of the chronic pain grade

To verify the reliability and validity of a Brazilian Portuguese version of the chronic pain grade (CPG-Br). Cultural adaptation was made in accordance with established guidelines, with modifications aiming at improving this process. Adaptations were made based on interviews with 45 chronic pain patients from So Paulo city. Validation was studied by concurrent application of the short-form-36 health survey (SF-36) and other questionnaires to 283 participants with chronic pain from the general population. Temporal stability was verified by a second application to 131 individuals. Factor analysis resulted in a two-factor solution with factors named characteristic pain intensity and activity limitation due to pain. Alpha coefficients of 0.78 and 0.70 and intraclass correlation coefficients of 0.76 and 0.72 for each factor indicated good internal consistency and temporal stability. Significant correlations between CPG-Br and SF-36, Roland-Morris disability questionnaire and neck disability index scores were noted. A consistent linear trend was also observed between pain grades and SF-36 scores. Frequency of use of pain medications and of pain-related medical visits increased with pain grade. This Brazilian Portuguese version of the chronic pain grade, tested on a sample of the Brazilian population, demonstrated good reliability and validity.

Adaptação transcultural e consistência interna do Early Trauma Inventory (ETI)

As experiências traumáticas precoces são um fator de risco preditivo de problemas psicopatológicos futuros. O Early Trauma Inventory (ETI) é um instrumento que avalia em indivíduos adultos experiências traumáticas ocorridas antes dos 18 anos de idade. Tal instrumento foi traduzido, transculturalmente adaptado e sua consistência interna foi avaliada. Vítimas de violência que preencheram os critérios de inclusão e exclusão foram submetidas a uma entrevista diagnóstica (SCID-I) e ao ETI. Foram incluídos 91 pacientes com o transtorno do estresse pós-traumático (TEPT). O alfa de Cronbach nos diferentes domínios variou de 0,595-0,793, e o escore total foi de 0,878. A maior parte dos itens nos vários domínios, com exceção do abuso emocional, apresentou índices de correlação interitem entre 0,51-0,99. A versão adaptada foi útil tanto na clínica quanto na pesquisa. Apresentou boa consistência interna e na correlação interitem. O ETI é um instrumento válido, com boa consistência para se avaliar a presença de história de traumas precoces em indivíduos adultos.

A study of the validity and reliability of the Brazilian version of the Body Shape Questionnaire (BSQ) among adolescents

OBJECTIVES: to produce evidence of the validity and reliability of the Body Shape Questionnaire (BSQ) - a tool for measuring an individual's attitude towards his or her body image. METHODS: the study covered 386 young people of both sexes aged between 10 and 18 from a private school and used self-applied questionnaires and anthropometric evaluation. It evaluated the internal consistency, the discriminant validity for differences from the means, according to nutritional status (underweight, eutrophic, overweight and obese), the concurrent validity by way of Spearman's correlation coefficient between the scale and the Body Mass Index (BMI), the waist-hip circumference ratio (WHR) and the waist circumference (WC). Reliability was tested using Wilcoxon's Test, the intraclass correlation coefficient and the Bland-Altman figures. RESULTS: the BSQ displayed good internal consistency (±=0.96) and was capable of discriminating among the total population, boys and girls, according to nutritional status (p<0.001). It correlated with the BMI (r=0.41; p<0.001), WHR (r=-0.10; p=0.043) and WC (r=0.24; p<0.001) and its reliability was confirmed by intraclass correlation (r=0.91; p<0.001) for the total population. The questionnaire was easy to understand and could be completed quickly. CONCLUSIONS: the BSQ presented good results, thereby providing evidence of its validity and reliability. It is therefore recommended for evaluation of body image attitudes among adolescents.

Assessing the validity of a food frequency questionnaire among low-income women in São Paulo, southeastern Brazil

This study describes the validity of a food frequency questionnaire (FFQ) in 93 low-income women (20-65 years), participating in a case-control study in São Paulo, Brazil. Two FFQ (FFQ1 and FFQ2, 12 months apart) and three 24-hour dietary recalls (24hR) were conducted between 2003 and 2004 to estimate dietary intake during the past year. The Pearson correlation coefficients (crude, energy-adjusted and de-attenuated) were used for comparisons between FFQ and 24hR. The agreement between the methods was further examined by the Bland-Altman analysis. For the assessment of long-term reliability, the energy-adjusted intra-class correlation coefficients were mostly around 0.40, but higher for vitamin A and folate (0.50-0.56). Energy-adjusted, attenuation-corrected Pearson validity correlations between FFQ and DR ranged from 0.30-0.54 for macronutrients to 0.20-0.48 for micronutrients, with higher value for calcium (0.75). There were small proportions of grossly misclassified nutrient intakes, while Bland-Altman plots indicated that the FFQ is accurate in assessing nutrient intake at a group level.

Validity and reliability of self-reported weight and height measures for the diagnoses of adolescent's nutritional status

OBJETIVO: Avaliar a validade do peso, estatura e Índice de Massa Corporal (IMC) referidos e sua confiabilidade para o diagnóstico do estado nutricional de adolescentes de Piracicaba. MÉTODOS: Participaram do estudo 360 adolescentes de ambos os sexos, de escolas públicas de Piracicaba, com idade entre 10 e 15 anos. Os adolescentes auto-relataram seu peso e estatura, sendo esses valores obtidos por medidas diretas, logo em seguida, pelos entrevistadores. A validade do IMC referido foi calculada segundo índices de sensibilidade, especificidade e valor preditivo positivo (VPP). Avaliou-se a concordância entre as categorias de IMC obtido por meio das medidas referidas e aferidas a partir do coeficiente kappa ponderado, coeficiente de correlação de Lin. e gráficos de Bland e Altman e Lin. RESULTADOS: Verificou-se que tanto os meninos quanto as meninas subestimaram o peso (-1,0 meninas e meninos) e a estatura (meninas -1,2 e meninos -0,8) (p < 0,001). Os valores de IMC aferidos e referidos apresentaram uma concordância moderada. A sensibilidade do IMC referido para classificar os indivíduos obesos foi maior para os meninos (87,5%), enquanto a especificidade foi maior para as meninas (92,7%). O VPP foi elevado somente para a classificação da eutrofia. CONCLUSÕES: As medidas referidas de peso e estatura de adolescentes não representam medidas válidas e, portanto, não devem ser usadas em substituição aos valores mensurados. Além disso, verificou-se que 10% dos meninos obesos e 40% das meninas obesas poderiam permanecer não identificados utilizando-se as medidas auto-referidas, confirmando a baixa validade das medidas auto-referidas.

Growth Hormone Receptor Exon 3 Isoforms and Their Implication in Growth Disorders and Treatment

Human recombinant growth hormone (hGH) has been used to treat short stature in several different conditions, but considerable inter-individual variation in short- and long-term growth response exists. Pharmacogenomics can provide important insights into hGH therapy. The GH receptor (GHR) is the first key molecule mediating GH action. In the past 3 years, a common GHR polymorphism reflecting the presence (GHRf1) or absence (GHRd3) of exon 3 has been under intensive investigation regarding its influence on the response to hGH therapy. Studies that evaluated response to GH treatment determined by these two GHR isoforms in children with GH deficiency, girls with Turner syndrome, children born small for gestational age and patients with acromegaly showed that patients carrying the GHRd3 allele demonstrated a greater GH sensitivity than patients homozygous for the GHRf1 allele. Other studies presented contradictory data, however, which may be caused by confounding factors such as small sample sizes and differences in experimental design. This GHR exon 3 genotype is the first identified genetic factor found to modulate the individual response to GH therapy. This article reviews the historical aspects and pharmacogenetic studies published to date in relation to this GHR polymorphism. The analyses of present and future validation studies may define the use of this and other polymorphisms in clinical practice, moving from pharmacogenetics to routine application and allowing individualization of hGH doses to optimize final outcome. Copyright (C) 2009 S. Karger AG, Basel

Portuguese version of the Delirium Rating Scale-Revised-98: reliability and validity

Objective To assess the validity and the reliability of the Portuguese version of the Delirium Rating Scale-Revised-98 (DRS-R-98). Methods The scale was translated into Portuguese and back-translated into English. After assessing its face validity, five diagnostic groups (n = 64; delirium, depression, dementia, schizophrenia and others) were evaluated by two independent researchers blinded to the diagnosis. Diagnosis and severity of delirium as measured by the DRS-R-98 were compared to clinical diagnosis, Mini-Mental State Exam, Confusion Assessment Method, and Clinical Global Impressions scale (CGI). Results Mean and rnedian DRS-R-98 total scores significantly distinguished delirium from the other groups (p < 0.001). Inter-rater reliability (ICC between 0.9 and 1) and internal consistency (alpha = 0.91) were very high. DRS-R-98 severity scores correlated highly with the CGI. Mean DRS-R-98 severity scores during delirium differed significantly (p < 0.01) from the post-treatment values. The area under the curve established by ROC analysis was 0.99 and using the cut-off Value of 20 the scale showed sensitivity and specificity of 92.6% and 94.6%, respectively. Conclusion The Portuguese version of the DRS-R-98 is a valid and reliable measure of delirium that distinguishes delirium from other disorders and is sensitive to change in delirium severity, which may be of great value for longitudinal studies. Copyright (c) 2007 John Wiley & Sons, Ltd.

Intra and inter-examiner reliability of the subacromial impingement index

The present study aimed to assess the reliability of intra and inter-examiner subacromial impingement index (SII) measures obtained from radiographs. Thirty-six individuals were enrolled and divided into two groups: control group, composed of 18 volunteers in good general health without shoulder problems, and a group of 18 patients with subacromial impingement syndrome (SIS). Radiographic images were taken with the dominant upper limb in neutral rotation, while the volunteers held their arm at 90A degrees of abduction in the frontal plane. The beam of radiation at 30A degrees craniocaudal inclination was used to provide an antero-posterior image view. Three blinded examiners each performed three measurements from the subacromial space (SS) and the anatomical neck of the humerus (NH). The SII was calculated as the ratio of the SS and the NH measures. The mean values of SII were compared using t-tests. The intra-class correlation coefficient (ICC) was used to assess intra- and inter-examiner reliability of the measures. The mean values of SII were greater for the control group (0.12) than for the SIS group (0.08; p = 0.0071). SII measurements showed excellent intra (0.96-0.99) and inter-examiner reliability (0.94) for both the control and SIS group. The results of this study show the potential use of the SII; a greater mean value for the control group compared to the SIS group and excellent reliability for intra- and inter-examiner measurement. Validation studies of the index should be conducted to correlate the index with clinical findings from subacromial impingement syndrome.

Expanded protocol of orofacial myofunctional evaluation with scores: Validity and reliability

Objective: Clinical evaluation of the stomatognathic system is indispensable for the diagnosis of orofacial myofunctional disorders. In order to obtain a more precise diagnosis, the protocol of orofacial myofunctional evaluation with scores (OMES protocol) (Int. J. Pediatr. Otorhinolaryngol. 72 (2008) 367-375) was expanded in terms of number of items and scale amplitude. The proposal of this study is to describe the expanded OMES protocol (OMES-E) for the evaluation of children. Validity of the protocol, reliability of the examiners and agreement between them were analyzed, as also were the sensitivity, specificity and predictive values of the instrument. Methods: The sample consisted of videorecorded images of 50 children, 25 boys (mean age = 8.4 years, SD = 1.8) and 25 girls (mean age = 8.2 years, SD = 1.7) selected at random from 200 samples. Three speech therapists prepared for orofacial myofunctional evaluation participated as examiners (E). The OMES and OMES-E protocols were used for evaluation on different days. E1 evaluated all images, E2 analyzed children with recordings from 1 to 25 and E3 analyzed children with recordings from 26 to 50. The validity of OMES-E was analyzed by comparing the instrument to the OMES protocol using the Pearson correlation test complemented with the split-half reliability test (p < 0.05). The linear weighted Kappa coefficient of agreement (Kw`), the sensitivity, specificity and predictive values and the prevalence of OMD were calculated. Results: There was a statistically significant correlation between the OMES and OMES-E protocols (0.79 > r < 0.94, p < 0.01) and a significant test-retest correlation with the OMES-E (0.75 > r < 0.86, p < 0.01), with a reliability range of 0.86-0.93. The correlation and reliability coefficients between examiners were: E1 x E2 (r = 0.74, 0.84), E1 x E3 (r = 0.70, 0.83) (p < 0.01). Kw` coefficients with moderate and good strength predominated. The OMES-E protocol presented mean sensitivity = 0.91, specificity = 0.77, positive predictive value = 0.87 and negative predictive value = 0.85. The mean prevalence of OMD was 0.58. Conclusion: The OMES-E protocol is valid and reliable for orofacial myofunctional evaluation. (C) 2010 Elsevier Ireland Ltd. All rights reserved.