On a scatter plot, the x axis of the graph relates to one group and the y axis to the other. On the graph, each point the percentage with this experience and its position on the graph is determined by the percentage of each of the groups being compared who have had these experiences. Points above the straight line running at an angle of 45° indicatate that the group on the y axis (in this case Protestants) are more likley to have had this experience and points below this line indicate that the group on the x axis (in this case Catholics) are more likely to have had this experience.
There are 17 data points on the chart (a close friend injured and a close relative killed are both at the same point, 11% Protestants and 9% Catholics). Four of these, Protestants are slightly more likely than Catholics to have experienced the following events: a close friend killed, a close relative killed, a close friend injured, and to have witnessed a bomb explosion, but these differences are not statistically significant. In fact, for ten of the 17 experiences there are no statistically significant differences between Catholics and Protestants. The most striking and statistically significant differences are that Catholics were 4.4 times as likely to have experienced a house search by the police and/or army, 1.5 times as likely to know someone imprisoned because of the conflict, 1.4 times as likely to have had a close relative injured and 1.3 times as likely to have witnessed gunfire and an assault. [Catholics are 2.3 times as likely to have been injured themselves but this result cannot be regarded as statistically valid because of small cell sizes.]
The Northern Ireland PSE living standards survey gathered evidence from a representative sample of 988 households with 2,311 individuals – 624 children (under 18 years old) and 1,687 adults. Of the adults, 80% agreed to answer the ten Troubles questions.