[A non invasive method for assessing sexual development at adolescence].

Introduction: Observational assessments of puberty that invades the adolescent's privacy are not acceptable for research in population groups. Results based on self assessment have been variable, and in many cases poor.

Objectives: To evaluate the validity of a questionnaire with simple questions addressed to assess early, intermediate and advanced puberty periods rather than specific stages.

Material And Methods: In an outpatient clinic at the Service of Adolescence of a public hospital, 188 and 142 healthy girls and boys aged 8-18 years, and 36 girls and boys aged 8-9 years attending a public school were studied. Adolescents attended the Service for the first time. Those with chronic diseases were excluded from the study. Children answered the questionnaire before entering the doctor's office, where a trained professional clinically assessed their puberal development (Tanner's stage). The questionnaire was previously tested in 30 adolescents.

Results: The highest concordance were found in the questions: "Have you started puberty?", with Tanner's stages III, IV or V (Kappa value= 0.60); "Have you already had your first menstrual period?" with stages IV-V (K= 0.69); and "Do you shave?" with stages IV-V (K= 0.66). In most cases, these questions showed high (> or = 0.80) sensitivity and specificity for detecting the mentioned puberty periods.

Conclusions: The method showed to be reliable, and its further evaluation in a non medical setting (schools, households, etc.) is recommended.