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1) Um novo teste de diagnóstico foi desenvolvido para detectar uma determinada doença cardíaca. Em um estudo clínico com 1.000 pacientes, 200 têm a doença e 800 não a têm. O teste apresenta os seguintes resultados: • Verdadeiros Positivos (VP): 180 • Falsos Positivos (FP): 100 • Verdadeiros Negativos (VN): 700 • Falsos Negativos (FN): 20 a) Calcule a sensibilidade do teste b) Calcule a especificidade do teste c) Determine o valor preditivo positivo (VPP) e o valor preditivo negativo (VPN) do teste. d) Descreva o que significam a sensibilidade e a especificidade em termos da eficácia do teste clínico. 2) Um teste de triagem para diabetes foi aplicado a uma população de 2.000 pessoas, das quais 300 foram diagnosticadas com diabetes. O teste possui uma sensibilidade de 90% e uma especificidade de 85%. a) Quantas pessoas foram corretamente identificadas como tendo diabetes Pesquisa em Saúde I – Sensibilidade e Especificidade Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User (Verdadeiros Positivos)? (Dica: VP = Sensibilidade × número de casos de diabetes) b) Quantas pessoas foram erroneamente identificadas como tendo diabetes (Falsos Positivos)? (Dica: FP = (1 - Especificidade) × número de pessoas sem diabetes) c) Quantas pessoas foram corretamente identificadas como não tendo diabetes (Verdadeiros Negativos)? d) Baseado nos resultados acima, quantas pessoas não diagnosticadas com diabetes realmente têm a doença (Falsos Negativos)? e) Se você fosse responsável por recomendar este teste para uso em larga escala, quais considerações faria com base nos valores de sensibilidade e especificidade? 3) Dois pediatras querem investigar um novo teste de laboratório que identifica infecções por estreptococos. O Dr. Hugo usa o teste de cultura padrão, que tem uma sensibilidade de 90% e especificidade de 96%. Já a Dra Carol usa o novo teste, que é 96% sensível e 96% específico. Se 200 pacientes forem submetidos à cultura com ambos os testes, qual das seguintes opções está correta? a) Dr. Hugo irá identificar corretamente mais pessoas com infecção por estreptococos do que a Dra. Carol b) Dr. Hugo irá identificar corretamente menos pessoas com infecção por estreptococos do que a Dra. Carol c) Dr. Hugo irá identificar corretamente mais pessoas sem infecção Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User MobileUser Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User estreptocócica do que a Dra. Carol d) A prevalência de infecção estreptocócica é necessária para determinar que pediatra irá identificar corretamente o maior número de pessoas com a doença 4) Um teste de triagem é usado da mesma maneira em duas populações semelhantes, mas a quantidade de resultados falso-positivos entre aqueles que testam positivo na população A é menor do que entre aqueles que testam positivo na população B. Qual é a explicação provável para este achado? a) É impossível determinar o que causou a diferença b) A especificidade do teste é menor na população A c) A prevalência da doença é menor na população A d) A prevalência da doença é maior na população A e) A especificidade do teste é maior na população A Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User Mobile User