## 8.4 CI for odds ratios

*(This question continues Question 7.8.2.)*

The timing of pubertal maturation can vary, which can have impacts upon behaviour. A large study (Duncan et al. 1985) studied 'the relationships between maturational timing and body image, school behavior, and deviance.'

Sample data were collected from

...children and youth of the entire United States drawn by the National Center for Health Statistics... known as the National Health Examination Survey (1966--1970). Data were collected on... adolescents' physical and psychological status...

--- Duncan et al. (1985)

The researchers asked the RQ;

For US children, is the odds of a boy maturing late the

sameas the odds of a girl maturing late?

Part of the data are shown entered into jamovi and SPSS (Fig. 8.6)

- For the \(2,864\) males in the sample, \(352\) were classified as maturing late.

For the girls, \(336\) of the \(2,664\) matured late. Use this information to construct a two-way table of sex against maturation time (Table 8.1).

Matured late | Did not mature late | Total | |
---|---|---|---|

Males | |||

Females | |||

Total | 5528 |

- What graphical summary could be used to display the information? Sketch this display.
- Among the boys, compute the
*odds*of maturing late. Interpret this value. - Among the girls, compute the
*odds*of maturing late. Interpret this value. - From the table, compute the odds ratio of a boy maturing late compared to a girl maturing late. Interpret this value, using the software output (Fig. 8.7; Fig. 8.8).

- What is the
**parameter**of interest? - Write down the OR and the \(95\)% CI for the OR from the jamovi or SPSS output. What does it mean?
- Compile the numerical summary table for these data (Table 8.2).
- Are boys generally more likely to mature later than girls?
**Vote below.**

Justify your answer.

Percentage maturing late | Odds maturing late | Sample size | |
---|---|---|---|

Males | |||

Females | |||

Odds ratio |

### References

Duncan PD, Ritter PL, Dornbusch SM, Gross RT, Carlsmith JM. The effects of pubertal timing on body image, school behavior, and deviance. Journal of Youth and Adolescence. 1985;14(3):227–35.