The Intensive Care Outcome Network study (ICON) began in 2006.  There are currently fifteen hospitals in England whose intensive care units (ICU) are taking part in the study.  For a list of these hospitals, please click here.

Every month the ICU department at each of these fifteen hospitals sends the ICON study the names and addresses of the patients who have spent time on their ICU unit. 

The ICON study office then invites these patients to participate in the ICON study by completing postal questionnaires.  The questionnaires ask about the patient’s state of health on the day the questionnaire is completed. 

Questionnaires are sent out at three specific intervals after the patient’s stay in intensive care at three months, twelve months, and two years after leaving ICU. 

By asking questions about the patient’s state of health over a period of two years, the study can gather information that reveals whether or not the patient’s health has improved, stayed the same or deteriorated.

Since the ICON study started in 2006, more than 7,000 former ICU patients have taken or are taking part in the study (November 2011).   

The importance of this study is that it is the largest study of its kind. Previous studies have been based on a smaller number of participants.  Previous studies have also concentrated on different aspects of ICU care, for example how many patients die whilst in ICU, how many patients die in hospital before they are discharged home.  Other studies have only followed up patients for 28 days after their discharge from ICU. 

The ICON study is different because it is collecting data from patients for up to two years post-ICU which will enable health professionals in the future to identify groups of patients who are at the most risk of long-term problems and the nature of these long-term problems. 

Some of the problems patients often suffer after intensive care include post-traumatic stress disorder (PTSD), anxiety, depression, and nightmares.

The ICON study will also provide a source of information for future health professionals who are interested in finding out which illnesses are most likely to cause patients long-term problems, either psychically or psychologically.