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This study aimed to determine whether self-assessed puberty is sufficiently reliable and valid to substitute for physician examination when feasibility of physician examination is low (e.g., behavioral research). Adolescents (convenience sample N = 178 endocrinology patients and N = 125 from educational trial; mean age 12.7 and 11.3 years, respectively) participated. Self-assessments were validated against physician Tanner ratings and by associations with bone density, gender, and age. Highest exact agreement between physicians and adolescents was 54% for females' and 55% for males' ratings of pubic hair. More than 85% agreement within one stage was obtained for most measures. Significant associations were found for age and bone between adolescents in earlier and later stages of development and for developmental stage between genders for each age group. Results suggest predictive and discriminate validity of self-assessments. Selfassessments may be useful when estimates of pubertal development are sufficient and for studies barred from physician examination.Pubertal stage and time of puberty are associated with risk behaviors and consequential morbidity. Early pubertal development, as measured by the onset of menarche or secondary sexual characteristics (both male and female),

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PURPOSE To test effects of parent/child training designed to increase calcium intake, bone-loading physical activity (PA), and bone density. DESIGN Two-group randomized controlled trial. SETTING Family-based intervention delivered at research center. SUBJECTS 117 healthy children aged 10-13 years (58.1% female, 42.7% Hispanic, 40.2% White). Ninety-seven percent of participants had at least one parent graduate from high school and 37.2% had at least one parent graduate from a 4-year university. INTERVENTION Children and parents were randomly assigned to diet and exercise (experimental) or injury prevention (control) interventions. Children were taught in eight weekly classes how to engage in bone-loading PA and eat calcium-rich foods or avoid injuries. Parents were taught behavior management techniques to modify children’s behaviors. MEASURES Measures at baseline, three, nine and twelve months included 24-hour diet and PA recalls, and bone mineral density (BMD) by DXA. ANALYSIS ANOVA and Generalized Estimating Equations assessed group by time differences. Comparisons were conducted separately for boys and girls. RESULTS For boys, cross-sectional differences between experimental versus control group were achieved for 3 and 9-month calcium intake (1352 vs. 1052mg/day, 1298 vs. 970mg/day, p<0.05). For girls, marginal cross-sectional differences were achieved for high-impact PA at 12 months (p<0.10). For calcium intake, a significant group by time interaction was observed from pre to post test for the full sample (p=.008) and for girls (p=.006) but not for boys. No significant group by time differences in calcium were observed across the follow-up period. No group by time differences were observed for high impact physical activity. Among boys, longitudinal group by time differences reached significance for total hip BMD (p=.045) and femoral neck BMD (p=.033), even after adjusting for skeletal growth. Similar differential increases were observed among boys for BMC at the hip (p=.068) and total body (p=.054) regions. No significant group by time interaction effects were observed for girls at any bone site for BMD. For BMC, control girls showed a significant increase (p=.03) in spine BMC compared to intervention girls CONCLUSION This study demonstrated that parent/preteen training can increase calcium intake and attenuate the decline in high-impact PA. Results suggest that more powerful interventions are needed to increase activity levels and maximize bone mineral accrual during pre-adolescent years.