Depression in adolescence or adolescence depression is one of the important and crucial adolescent issues which is often ignored (by the parents).

Depression, like any other physical ailment, is not visible on the surface and the subsequent behaviour associated with is often considered as "childhood arrogance".

But the picture isn't as rosy and simple as it may sound so.

Child psychiatrists have often spoken about the importance of identifying adolescent depression by understanding the symptoms.

Now, researchers have tried and developed a tool that can recognise adolescents who are at high or low risk of depression during adolescence.

The study has been published in the Journal of the American Academy of Child and Adolescent Psychiatry.

It also evaluated the performance of the tool in samples of adolescents from New Zealand and the UK.

The tool demonstrated differences in its ability to predict depression across these countries and highlighted the need to consider local variations when developing predictive tools.

The researchers, in the study, tried to go beyond more traditional ways of identifying youths at high risk of depression.

They learned from other medical specialties that combine multiple variables to generate composite risk scores, such as the Framingham cardiovascular risk score.

"This study procedure is relatively new in the field of mental health," the researchers said.

Predictive tools have already been developed for psychosis and many physical health conditions, but little has been done for depression, despite its prevalence.

Current methods for assessing the risk of depression are based on family history and sub-threshold symptoms which do not reach the criteria for depression.

Based on existing research and clinical expertise the researchers identified 11 socio-demographic variables that could be combined into a single score to recognise those adolescents at risk of developing depression.

In addition to a strong association with depression the variables were chosen because they were also easy to collect and simple to evaluate.

Using data on these 11 variables from 2,192 Brazilian 15-year-old adolescents and mental health assessments of the same adolescents at 18 years old, the researchers developed the tool to assess the risk of development of a major depressive disorder.

The study compared the ability of this tool to predict depression in a sample of 1,144 British 12 year olds (no data was available at age of 15) from the E-Risk Study and 739 New Zealand 15 year olds from the Dunedin study.

The predictive ability of the score was not as strong in the UK and New Zealand samples.

According to researchers, this was to some extent expected as not all the information used from the Brazilian sample was available in the other datasets and different diagnostic measures were used to assess mental health at 18 years old.

The researchers added that the existence of these discrepancies do not discount the value of the tool but provides important insight into adapting the score according to where it will be used.