Suicide seasonality: Evidence of 11-year cyclic oscillations in Brazilian suicide rates

Sazonalidade do suicídio: Indícios de oscilações cíclicas de 11 anos nas taxas de suicídio brasileiras

Abstracts

Several researchers have studied suicide seasonality through different statistical approaches. In the present research, we performed a detailed statistical study of Brazilian suicide data registered from 1980 to 2010 using a new approach known as Threshold Bias Model (TBM). Eleven-year cyclic oscillations were observed in suicide rates that, at first sight, appear as being negatively correlated with the cycles of solar activity. Such oscillations are more noticeable for males although they also have been observed in the female rates.

suicide; seasonal variations; solar activity

Vários pesquisadores têm estudado a sazonalidade do suicídio utilizando diversas abordagens estatísticas. Na presente pesquisa, realizamos um estudo estatístico dos dados de suicídio brasileiros registrados entre 1980 e 2010 utilizando uma nova abordagem conhecida como Modelo da Tendência Limiar (TBM). Foram observadas oscilações com período de 11 anos nas taxas de suicídio que, à primeira vista, parecem ser negativamente correlacionadas com os ciclos de atividade solar. Essas oscilações foram mais notáveis nas taxas masculinas, ainda que também tenham sido observadas nas taxas femininas.

suicídio; variações sazonais; atividade solar

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Publication Dates

• Publication in this collection
  26 Aug 2013
• Date of issue
  Mar 2013

History

• Received
  04 Oct 2012
• Accepted
  07 Jan 2013