Passage: The reported prevalence of TS varies "according to the source, age, and sex of the sample; the ascertainment procedures; and diagnostic system", with a range reported between .4% and 3.8% for children ages 5 to 18. Robertson (2011) says that 1% of school-age children have Tourettes. According to Lombroso and Scahill (2008), the emerging consensus is that .1 to 1% of children have Tourettes, with several studies supporting a tighter range of .6 to .8%. Bloch and Leckman (2009) and Swain (2007) report a range of prevalence in children of .4 to .6%, Knight et al. (2012) estimate .77% in children, and Du et al. (2010) report that 1 to 3% of Western school-age children have Tourettes.
How many percentage points difference does Swain report is the range of prevalence of Tourettes in children.? How many years after Du et al.'s report came out was the Knight et al. report released? How many years after the Bloch and Leckman study was the Knight et al. study? How many years is the age range where the range reported is between .4% and 3.8 in children%? In whose report was the percentage of school-age children with Tourettes estimated between .5% and .8%? Which report came out first, Du et al. or Knight et al.? Which report lists the second highest range estimate? Which report lists the second smallest percentage? Which study occurred last, Swain or Bloch and Leckman? Which study reports a higher percentage of children have Tourettes, Bloch and Leckman or Knight et al.?