A OMS volta a tentar, ou alguém na OMS com decência ética, alertar para o pandemónio de testes sem critério.
Alertam que testes positivos sem sintomas não são diagnóstico, são lixo. Que o números de ciclos deve ser publicado e que o risco da falsos positivos aumenta com descida de prevalência.
Alertam para séculos de prática clínica e estatística de testes. Dizem aos colaboracionistas que estão a ignorar critérios mínimos de prática clínica decente.
“…careful interpretation of weak positive results is needed (1). The cycle threshold (Ct) needed to detect virus is inversely proportional to the patient’s viral load. Where test results do not correspond with the clinical presentation, a new specimen should be taken and retested using the same or different NAT technology.
WHO reminds IVD users that disease prevalence alters the predictive value of test results; as disease prevalence decreases, the risk of false positive increases (2). This means that the probability that a person who has a positive result (SARS-CoV-2 detected) is truly infected with SARS-CoV-2 decreases as prevalence decreases, irrespective of the claimed specificity.
Most PCR assays are indicated as an aid for diagnosis, therefore, health care providers must consider any result in combination with timing of sampling, specimen type, assay specifics, clinical observations, patient history, confirmed status of any contacts, and epidemiological information.”
