Parameters to increase the quality of iridology studies: A scoping review



Iridology is an applied health practice whose overall aim is to better understand the constitution of an individual. There are a range of new methods which can be used to acquire and interpret images but these have not as yet been reviewed. This scoping review aims to build on previous reviews and explore publications from 2014 to 2019.


This scoping review focuses on advances in iridological research methods and equipment. It followed the PRISMA-ScR guidelines and the Joanna Briggs Institute framework. The search strategy was designed in collaboration with the health sciences librarian, the principal investigator, and the researcher’s supervisors. Six relevant databases were identified. The form created prior to data extraction was used to review each article.


Twenty-three publications out of a total of ninety-three publications identified were included. Four main themes emerged: (1) five different types of equipment are currently used to capture iris images in humans, (2) three different iridology-related theoretical frameworks were incorporated into the various research designs, (3) two major software-based techniques were employed to evaluate iridological signs, and, (4) sixteen of the reviewed articles linked a specific pathology or syndromic health condition of the human body represented to the reflex iris map of the eyes.


Computerized technological advancements in the field of iridology have helped to improve the clarity and detail of iris images and the ability to relate iridological signs to human health. The findings of this review can guide the design and methodological choices for future iridology studies.

European Journal of Integrative Medicine

Volume 43, April 2021, 101311