Table 1.
Bivariate correlations of self-reported age at menarche for annual in-person interviews and quarterly phone interviews
| Year 1 | Year 2 | Year 3 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| ||||||||||||
| Annual | 3 mo | 6 mo | 9 mo | Annual | 3 mo | 6 mo | 9 mo | Annual | 3 mo | 6 mo | 9 mo | |
| Year 1 | ||||||||||||
| Annual (n = 209) | -- | |||||||||||
| 3 month (n = 212) | .74 | -- | ||||||||||
| 6 month (n = 211) | .74 | .68 | -- | |||||||||
| 9 month (n = 218) | .67 | .63 | .72 | -- | ||||||||
|
| ||||||||||||
| Year 2 | ||||||||||||
| Annual (n = 192) | .78 | .72 | .78 | .75 | -- | |||||||
| 3 month (n = 211) | .63 | .67 | .68 | .64 | .69 | -- | ||||||
| 6 month (n = 208) | .67 | .68 | .74 | .76 | .74 | .74 | -- | |||||
| 9 month (n = 206) | .61 | .59 | .70 | .64 | .76 | .61 | .66 | -- | ||||
|
| ||||||||||||
| Year 3 | ||||||||||||
| Annual (n = 203) | .74 | .64 | .70 | .63 | .81 | .67 | .66 | .64 | -- | |||
| 3 month (n = 203) | .63 | .67 | .66 | .70 | .66 | .65 | .65 | .59 | .73 | -- | ||
| 6 month (n = 194) | .61 | .55 | .61 | .63 | .63 | .61 | .65 | .60 | .65 | .69 | -- | |
| 9 month (n = 194) | .60 | .64 | .62 | .63 | .64 | .61 | .60 | .63 | .68 | .75 | .62 | -- |
Note. All correlations are significant at p < .01. Annual represents in-person interviews, whereas 3 month, 6 month, and 9 month represent phone interviews. Bolded correlations are between annual in person visits. n at each assessment represents non-missing reports of age at menarche (i.e., does not include girls who were premenarcheal or missed the visit); 253 girls reported age at menarche at least twice across the course of the study.