Stroke 2

• Fill in the blanks

  A) Randomised controlled trial

  B) Non-randomised control tiral

  C) Cohort study

  D) Case-control study

  E) Cross-sectional study

  F) Cross-sectional study

  G) Ecologic study

  H) Case report/series

  
• What are the strengths of case control studies?

  Informative -> investigate multiple potential casual exposures in 1 study

  Efficient -> well-suited to rare diseases

  Ideal when long latency between exposure & disease

  Can be carried out relatively quickly & inexpensively
• What are the limitations of case control studies?

  Susceptible to baises (recall bias, interviewer bias, selection bias)

  Information on exposures may rely on inaccurate & incomplete historical records
• What is an odds ratio?

  Measure of association between an exposure & an outcome

  Can be used to determine whether a variable of interest is a risk factor for the outcome of interest
• What is the interpretation of odds ratios?

  OR = 1 (exposure is not associated with outcome)

  OR > 1 (exposure associted with higher odds of outcome)

  OR < 1 (exposure associated with lower odds of outcome)
• What is a population attributable fraction?

  Proportion of incidents in the population that are attributable to the risk factor
• How can the population attributable fraction (PAF) be calculated?

  Proportion of cases who were exposed to the risk factor x (1 - 1/adjusted odds ratio)