The ratio of the lengths of the index finger and the ring finger in males is predictive of a variety of disorders related to disturbed hormonal balance, according to a recent study.

Researchers found that when the index finger is shorter than the ring finger, this results in a small 2D:4D ratio, pointing to a high exposure to testosterone in the uterus. This may indicate risk of schizophrenia in males.

Schizophrenia is a mental disorder in which people interpret reality abnormally.

For the study, researchers collected and analyzed data of more than 100 male patients diagnosed with schizophrenia and 100 matched healthy male individuals.

They found that the 2D:4D ratio may be an effective predictor of schizophrenia -- there were significant differences between schizophrenia and control groups concerning the ratio of the lengths of the second digit to the fourth digit, as well as its asymmetry, in both hands.

"Asymmetry index showed moderate discriminatory power and, therefore asymmetry index has a potential utility as a diagnostic test in determining the presence of schizophrenia," Dr. Taner Oznur, co-author of the study, said in a statement.

The findings are detailed in the journal Clinical Anatomy.