Figure 1:

Flow chart of the age at menarche assignment algorithm for 946 girls with an ascertained age. Median and IQR were computed from the survival distribution using SAS Proc PHREG with an additional strata statement adjusting for site.

1. Agree = difference within 6 months.

2. Disagree = difference 6+ months.

3. At least one report.

A. First reported date/age was used to determine age at menarche.

B. The first girl reported date was used as a tie breaker. If the first girl reported date was within 6 months of the first parent reported date, then first parent reported date was used. If the first girl reported date was within 6 months of the second parent reported date, then the second parent reported date was used. If there is no agreement among all dates, the first parent reported date was used.

C. The third girl reported date was used as a tie breaker. If the third girl reported date was within 6 months of the first girl reported date, then the first girl reported date was used. If the third girl reported date was within 6 months of the second girl reported date, then the second girl reported date was used. If there is no agreement among all dates, the first girl reported date was used.

D. Third parent reported age was used as a tie breaker. If the third parent reported age was within 6 months of the first parent reported age, then the first parent reported age was used. If the third parent reported age was within 6 months of the second parent reported age, the second parent reported age was used. If there is no agreement among all ages, the first parent reported age was used.

E. Age at menarche was computed as nine months prior to first affirmative response to menarche.