4.2 Percentages and odds
In a study of how well emergency dispatchers recognised signs of stroke (Oostema et al. 2018), the data in Table 4.1 were collected.
Dispatcher suspected stroke | Dispatcher missed stroke | |
---|---|---|
Males | 67 | 43 |
Females | 97 | 39 |
- Why are the levels 'Male' and 'Female' placed in the rows of the table, rather than the columns?
- What proportion of patients had their stroke symptoms missed?
- Sketch a side-by-side or stacked bar chart to display the data.
- Of the male patients, what proportion had their stroke symptoms missed by the dispatcher?
- Of the female patients, what proportion had their stroke symptoms missed by the dispatcher?
- For the male patients, what are the odds that they had their stroke symptoms missed by the dispatcher?
- For the female patients, what are the odds that they had their stroke symptoms missed by the dispatcher?
- What is the difference between the proportions of stroke symptoms being missed by the dispatcher, comparing males to females?
- What is the odds ratio that a patients had their stroke symptoms missed by the dispatcher, comparing males to females?
- Construct a numerical summary table (see Table 4.2).
symptoms missed | symptoms missed | size | |
---|---|---|---|
Males | |||
Females | |||
Difference: | Odds ratio: |
References
Oostema JA, Chassee T, Reeves M. Emergency dispatcher stroke recognition: Associations with downstream care. Prehospital Emergency Care. 2018;22(4):466–71.