Tanner scale

The Tanner scale (also known as the Tanner stages) is a scale of physical development in children, adolescents and adults. The scale defines physical measurements of development based on external primary and secondary sex characteristics, such as the size of the breasts, genitals, testicular volume and development of pubic hair. This scale was first identified by James Tanner, a British pediatrician, and thus bears his name.

Due to natural variation, individuals pass through the Tanner stages at different rates, depending in particular on the timing of puberty. In HIV treatment, the Tanner scale is used to determine which treatment regimen to follow (adult, adolescent or pediatric).

Adapted from text by Lawrence Neinstein, M.D.

The scale has been criticized by the pornography industry for its potential to lead to false child pornography convictions, such as in the case when US federal authorities used it to assert that pornographic actress Lupe Fuentes was underage. Fuentes personally appeared at the trial and provided documentation that showed that the DVDs in question were legally produced. The author of the classification system himself has argued that age classification using the Tanner stages represents invalid use. Tanner stages do not match with chronological age, but rather maturity stages and thus are not diagnostic for age estimation.

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