A study reported by D. Goldberg in The Detection of Psychiatric Illness by Questionnaire (Oxford University Press, London, 1972, p. 126) examined the relationship between mental-health classification and thoughts of suicide.
The mental health of each person in a sample of 295 was classified as normal, mild psychiatric illness, or severe psychiatric illness.
Each person was asked, "Have you recently found that the idea of taking your own life kept coming into your mind?" Following are the results.

At the 5% significance level, is there evidence that an association exists between response to the suicide question and mental-health classification?

Mental health Mild Severe Normal illness illness Total Definitely 90 not 43 34 167 Don't think so 18 31 Crossed my min 3 21 2 45 Definitely 15 36 52 Total 97 295