Fig. 1From: The effect of a terrorist attack on emergency department inflow: an observation study using difference-in-differences methodologyThe estimated impact of the terrorist attack on ED inflow over time. Error bars indicate 95% confidence intervals. The graph confirms that no effect occurred prior to the attack (confirmation of the parallel trends assumption). The first and second week following the attack saw an average decrease in ED inflow of around 10% followed by an increase to normal levels in week 3 and forwardBack to article page