## 34.7 Quick review questions

A study of Chinese paedatric patients studied the relationship between the 6-minute walk distance (6MWD) and maximum oxygen uptake (VO2max) for $$n=29$$ patients. The correlation coefficient is reported as $$r=0.457$$, and the corresponding $$P$$-value as $$P=0.013$$.

1. The $$x$$-variable is
2. True or false: Since the $$P$$-value is small, the correlation must be quite strong.
3. The relationship is best described as
4. The value of $$R^2$$ (to one decimal place, expressed as a percentage) is:
5. For statistical validity, we need to assume that:

### References

Wong P-F, Chan EY-T, Ng DK-K, Kwok K-L, Yip AY-F, Leung S-Y. Correlation between 6-min walk test and cardiopulmonary exercise test in Chinese patients. Pediatric Respirology and Critical Care Medicine. Medknow Publications; 2018;2(2):32.