People with OCD are being urged to take part in a new online study.
Obsessive Compulsive Disorder includes thoughts about being contaminated or dirty, repeatedly checking locks or excessive need for symmetry and order.
Around a quarter of all people in the community experience a low level of it at some stage in their life.
Psychologist at NUI Galway Patrick McHugh who is leading the study says OCD can have a huge impact on a person’s life.
He said: “A person with a diagnosis of OCD will typically be affected by their symptoms for up to an hour or more a day.
“In fact, people with the diagnosis could be 4-6 hours a day affected by this symptom, so you can imagine a person trying to maintain employment, that can be really difficult.
“It may interfere with relationships also.”