Resumo A pandemia de COVID-19 tem desafiado pesquisadores e gestores a encontrar medidas de saúde pública que evitem o colapso dos sistemas de saúde e reduzam os óbitos. Esta revisão narrativa buscou sistematizar as evidências sobre o impacto das medidas de distanciamento social na epidemia de COVID-19 e discutir sua implementação no Brasil. Foram triados artigos sobre o efeito do distanciamento social na COVID-19 no PubMed, medRXiv e bioRvix, e analisados atos do poder público nos níveis federal e estadual para sumarizar as estratégias implementadas no Brasil. Os achados sugerem que o distanciamento social adotado por população é efetivo, especialmente quando combinado ao isolamento de casos e à quarentena dos contatos. Recomenda-se a implementação de medidas de distanciamento social e de políticas de proteção social para garantir a sustentabilidade dessas medidas. Para o controle da COVID-19 no Brasil, é imprescindível que essas medidas estejam aliadas ao fortalecimento do sistema de vigilância nos três níveis do SUS, que inclui a avaliação e uso de indicadores adicionais para monitorar a evolução da pandemia e o efeito das medidas de controle, a ampliação da capacidade de testagem, e divulgação ampla e transparente das notificações e de testagem desagregadas.

No abstract

Randomized clinical trials (RCT) are accepted as the gold-standard approaches to measure effects of intervention or treatment on outcomes. They are also the designs of choice for health technology assessment (HTA). Randomization ensures comparability, in both measured and unmeasured pretreatment characteristics, of individuals assigned to treatment and control or comparator. However, even adequately powered RCTs are not always feasible for several reasons such as cost, time, practical and ethical constraints, and limited generalizability. RCTs rely on data collected on selected, homogeneous population under highly controlled conditions; hence, they provide evidence on efficacy of interventions rather than on effectiveness. Alternatively, observational studies can provide evidence on the relative effectiveness or safety of a health technology compared to one or more alternatives when provided under the setting of routine health care practice. In observational studies, however, treatment assignment is a non-random process based on an individual’s baseline characteristics; hence, treatment groups may not be comparable in their pretreatment characteristics. As a result, direct comparison of outcomes between treatment groups might lead to biased estimate of the treatment effect. Propensity score approaches have been used to achieve balance or comparability of treatment groups in terms of their measured pretreatment covariates thereby controlling for confounding bias in estimating treatment effects. Despite the popularity of propensity scores methods and recent important methodological advances, misunderstandings on their applications and limitations are all too common. In this article, we present a review of the propensity scores methods, extended applications, recent advances, and their strengths and limitations.

Summary Background Although leprosy is recognised as a disease of poverty, there is little evidence on the specific socioeconomic factors associated with disease risk. To inform targeted strategies for disease elimination, we investigated socioeconomic markers of leprosy risk in Brazil. Methods Socioeconomic data from the 100 Million Brazilian Cohort were linked to the Brazilian national disease registry (Sistema de Informação de Agravos de Notificação) for leprosy from Jan 1, 2007, to Dec 31, 2014. Using Poisson regression, we assessed the association of socioeconomic factors with risk of incident leprosy in the full cohort and in children (aged 0–15 years), by leprosy subtype and region of residence. Findings In an analysis of 23 899 942 individuals including 18 518 patients with leprosy, increased levels of deprivation were associated with an increased risk of leprosy in Brazil. Directions of effect were consistent in children younger than 15 years and across disease subtypes. Individuals residing in regions with the highest poverty in the country (central-west, north, and northeast regions) had a risk of leprosy incidence five-to-eight times greater than did other individuals. Decreased levels of income and education and factors reflecting unfavourable living conditions were associated with an up to two-times increase in leprosy incidence (incidence rate ratio 1·46, 95% CI 1·32–1·62, for lowest vs highest quartile of income per capita; 2·09, 95% CI 1·62–2·72, for lowest vs highest level of education). Interpretation Within the poorest half of the Brazilian population, the most deprived individuals have the greatest risk of leprosy. Strategies focusing on early detection and treatment in the poorest populations could contribute substantially to global disease control. Funding Medical Research Council, Wellcome Trust, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Brazil), the Conselho Nacional das Fundações Estaduais de Amparo à Pesquisa, Economic and Social Research Council, Biotechnology and Biological Sciences Research Council, Conselho Nacional de Desenvolvimento Científico e Tecnológico, and Fundação de Apoio à Pesquisa do Distrito Federal.