FootbALL:  Cross-table for dementia 

Research on the Link Between Football (heading) and Dementia: A Cross-Table

Research could be undertaken to examine the link between playing football and dementia with the construction of a cross-table.  A sample of 200 people could be taken of 100 former footballers and 100 non-footballers.  The researcher would then want to find out, how many of those football players and non-players had dementia (or not).  This is shown, hypothetically, in the table below.

Cross-Table to Examine Dementia and Non-Dementia in Former-Footballers and Non-Footballers                                               

This is a simple table, although, the situation is complicated by how a researcher would decide whether a retired footballer has dementia or not.  This is the case, given that some footballers may deny having the disease. 

This table could be elaborated upon by dividing the 'footballer category' into three different sets: professional footballer, amateur footballer and non-footballer.