Scale for developmental dyslexia screening: evidence of validity and reliability. / Escala para rastreio de dislexia do desenvolvimento: evidências de validade e fidedignidade.

PURPOSE: To investigate the empirical validity and reliability of a screener for risk of developmental dyslexia (DD) by elementary school teachers. METHODS: The scale was tested with 12 teachers who answered questions about their students (95 students total, all in the third year of elementary school); the students, in turn, performed reading and writing tasks which were used to investigate the association between screening scores and performance. The following analyses were carried out: (1) factor analysis; (2) internal consistency; (3) relationship between each scale item and the construct of interest, as measured by item response theory (IRT); (4) correlation of each scale item with external variables (reading and writing tests); and (5) the temporal stability of teachers' evaluations. RESULTS: The analyses showed: (1) one factor was extracted; (2) strong internal consistency - the items in the scale are good indicators for screening of this construct; (3) items were monotonic (IRT), i.e., item variability is associated with one construct; (4) moderate Spearman correlation (11/17 items); (5) temporal stability - the result of screening did not vary over time. CONCLUSION: This study shows evidence of validity and reliability of the proposed scale in its intended use of screening for developmental dyslexia. The percentage of children at risk for developmental dyslexia, according to the scale, was approximately 9%, which is in agreement with the international literature on the prevalence of dyslexia.

OBJETIVO: Investigar validade e fidedignidade de uma escala de rastreio para dislexia do desenvolvimento (DD) no ensino fundamental preenchida por professores. MÉTODO: Avaliação empírica - 12 professores responderam a Escala de Leitura e Escrita (ELE) sobre 95 alunos de 3º ano do ensino fundamental, em dois momentos; os escolares realizaram testes de leitura e escrita (variáveis externas) para investigar a correlação entre a escala e o desempenho dos mesmos. Realizaram-se (1) análise fatorial, (2) avaliação da consistência interna, (3) investigação da relação entre um item da escala e o construto medido por teoria da resposta ao item (TRI) (4) correlação da escala com variáveis externas (Validade Convergente-VC); e (5) investigação da estabilidade temporal da avaliação. RESULTADOS: (1) a escala avalia um único fator; (2) o coeficiente alpha apontou que os itens são bons indicadores do construto; (3) a análise por TRI mostra que todos os itens foram monotônicos, indicando que um único construto determina a variabilidade (4) a correlação de Spearman foi moderada (11/17 itens), apontando a existência de VC; (5) o valor da correlação do coeficiente de estabilidade temporal indica que o resultado da ELE não varia de maneira significativa no tempo; (6) nove crianças obtiveram pontuações que sugerem encaminhamento para uma avaliação diagnóstica devido ao grau de dificuldade apresentado. CONCLUSÃO: O estudo mostra evidências empíricas de validade e fidedignidade da ELE para rastreio de risco de DD. A porcentagem de crianças com suspeita de DD (aproximadamente 9%) corrobora a literatura internacional sobre prevalência de dislexia.

Escala para rastreio de dislexia do desenvolvimento: evidências de validade e fidedignidade / Scale for developmental dyslexia screening: evidence of validity and reliability

Resumo Objetivo Investigar validade e fidedignidade de uma escala de rastreio para dislexia do desenvolvimento (DD) no ensino fundamental preenchida por professores. Método Avaliação empírica - 12 professores responderam a Escala de Leitura e Escrita (ELE) sobre 95 alunos de 3º ano do ensino fundamental, em dois momentos; os escolares realizaram testes de leitura e escrita (variáveis externas) para investigar a correlação entre a escala e o desempenho dos mesmos. Realizaram-se (1) análise fatorial, (2) avaliação da consistência interna, (3) investigação da relação entre um item da escala e o construto medido por teoria da resposta ao item (TRI) (4) correlação da escala com variáveis externas (Validade Convergente-VC); e (5) investigação da estabilidade temporal da avaliação. Resultados (1) a escala avalia um único fator; (2) o coeficiente alpha apontou que os itens são bons indicadores do construto; (3) a análise por TRI mostra que todos os itens foram monotônicos, indicando que um único construto determina a variabilidade (4) a correlação de Spearman foi moderada (11/17 itens), apontando a existência de VC; (5) o valor da correlação do coeficiente de estabilidade temporal indica que o resultado da ELE não varia de maneira significativa no tempo; (6) nove crianças obtiveram pontuações que sugerem encaminhamento para uma avaliação diagnóstica devido ao grau de dificuldade apresentado. Conclusão O estudo mostra evidências empíricas de validade e fidedignidade da ELE para rastreio de risco de DD. A porcentagem de crianças com suspeita de DD (aproximadamente 9%) corrobora a literatura internacional sobre prevalência de dislexia.

Abstract Purpose To investigate the empirical validity and reliability of a screener for risk of developmental dyslexia (DD) by elementary school teachers. Methods The scale was tested with 12 teachers who answered questions about their students (95 students total, all in the third year of elementary school); the students, in turn, performed reading and writing tasks which were used to investigate the association between screening scores and performance. The following analyses were carried out: (1) factor analysis; (2) internal consistency; (3) relationship between each scale item and the construct of interest, as measured by item response theory (IRT); (4) correlation of each scale item with external variables (reading and writing tests); and (5) the temporal stability of teachers' evaluations. Results The analyses showed: (1) one factor was extracted; (2) strong internal consistency - the items in the scale are good indicators for screening of this construct; (3) items were monotonic (IRT), i.e., item variability is associated with one construct; (4) moderate Spearman correlation (11/17 items); (5) temporal stability - the result of screening did not vary over time. Conclusion This study shows evidence of validity and reliability of the proposed scale in its intended use of screening for developmental dyslexia. The percentage of children at risk for developmental dyslexia, according to the scale, was approximately 9%, which is in agreement with the international literature on the prevalence of dyslexia.

PDMS Microlenses for Focusing Light in Narrow Band Imaging Diagnostics.

Minimally invasive medical devices can greatly benefit from Narrow Band Imaging (NBI) diagnostic capabilities, as different wavelengths allow penetration of distinct layers of the gastrointestinal tract mucosa, improving diagnostic accuracy and targeting different pathologies. An important performance parameter is the light intensity at a given power consumption of the medical device. A method to increase the illumination intensity in the NBI diagnostic technique was developed and applied to minimally invasive medical devices (e.g., endoscopic capsules), without increasing the size and power consumption of such instruments. Endoscopic capsules are generally equipped with light-emitting diodes (LEDs) operating in the RGB (red, green, and blue) visible light spectrum. A polydimethylsiloxane (PDMS) µ-lens was designed for a maximum light intensity at the target area of interest when placed on top of the LEDs. The PDMS µ-lens was fabricated using a low-cost hanging droplet method. Experiments reveal an increased illumination intensity by a factor of 1.21 for both the blue and green LEDs and 1.18 for the red LED. These promising results can increase the resolution of NBI in endoscopic capsules, which can contribute to early gastric lesions diagnosis.

Searching for the best approach to assess teachers' perception of inattention and hyperactivity problems at school.

Although major guidelines in the field and current diagnostic criteria clearly demand an assessment of children's attention deficit/hyperactivity disorder (ADHD) symptoms at school, few studies address the fundamental question of which is the best approach for clinicians to get this information from teachers. Three screening strategies for ADHD were applied to teachers of 247 third grade students. They were asked (1) an overt question about potential cases of ADHD in their classroom; (2) to complete a broad-band questionnaire assessing common child mental health problems; (3) to rate ADHD-specific symptoms in a narrow-band questionnaire. Based on the overt question, teachers identified one in five students (21.1 %) as having ADHD; 28 cases (11.3 %) were identified using standard cut-offs for the narrow-band, and 13 (5.3 %) using a standard threshold for the sub-scale of hyperactivity from the broad-band questionnaire. Agreement among strategies was low (k = 0.28). A subsample of students, clinically assessed to confirm screenings, showed modest agreement with final diagnosis. The narrow-band questionnaire had the best diagnostic performance. Multivariate analysis indicated that the presence of a comorbid externalizing disorder was the only variable associated with teachers' ascertainment of ADHD caseness or non-caseness. Choice of screening strategy significantly affects how teachers report on ADHD symptoms at school. The halo effect of externalizing behaviors impacts the correct identification of true cases of ADHD in the school setting. Clinicians can rely on narrow-band instruments like the SNAP-IV to get information on ADHD symptoms at school from teachers.

Increasing teachers' knowledge about ADHD and learning disorders: an investigation on the role of a psychoeducational intervention.

OBJECTIVE: To investigate elementary school teachers' baseline knowledge about ADHD and learning disorders (LD) and the impact of a strategy to increase awareness of these disorders. METHOD: A total of 37 teachers were selected from four elementary schools in the catchment area of the University Hospital, in Porto Alegre, Brazil. To evaluate teachers' knowledge, two self-report questionnaires about ADHD and LD were applied before and after an awareness program on these disorders. RESULTS: The intervention significantly increased teachers' knowledge of both disorders, even after adjustment for confounding factors (p < .001). In the repeated measures ANCOVA, only teachers' previous knowledge of ADHD/LD (p < .001) was significant in predicting score change in knowledge before and after the intervention. CONCLUSION: Results suggest the efficacy of a brief psychoeducational intervention program for increasing teacher awareness and knowledge about ADHD and LD. Future studies are warranted to confirm the efficacy and evaluate the long-term impact of this intervention.