## 4.1 Quick revision

We **strongly** recommend trying these *Quick revision* questions **before** your tutorial.

A study of obstructive sleep apnoea (OSA) in adults with Down Syndrome (de Carvalho et al. 2020) had \(n = 60\) adults (\(27\) females; \(33\) males) undergo a sleep study. The data are shown in Fig. 4.1.

- What would be an
**inappropriate**numerical summary for the age of the participants? - What might be an
**appropriate**way to numerically describe the amount of*variation*in the ages of participants?

- What might be an
**appropriate**way to numerically describe the average REI of participants?

- What might be an
**appropriate**way to numerically describe the gender of the participants?

- In the sample of \(n = 60\), what
**percentage**of individuals are females?

- In the sample of \(n = 60\), what are the
**odds**that an individual is female?

*Age*is quantitative, so odds are not appropriate (odds are used with qualitative data).- Variation is measured using standard deviation or IQR.
- The average value (of a quantitative variable) can be described using a mean or a median.
- Percentages or odds can be used to numerically summarise a qualitative variable like
*gender*. - \(27/60\times 100 = 45\)%.
- \(27/33 = 0.8181\).

### References

de Carvalho AA, Amorim FF, Santana LA, de Almeida KJQ, Santana ANC, Neves F de AR. STOP-Bang questionnaire should be used in all adults with Down Syndrome to screen for moderate to severe obstructive sleep apnea. PloS ONE. 2020;15(5):e0232596.