WHO global survey on the use of CT in asymptomatic individuals

WHO is conducting a global survey on the use of computed tomography (CT) in asymptomatic individuals for individual health assessment to gather information on the current status of this practice, existing policies and regulations in different regions of the world. This survey on the use of CT in asymptomatic individuals aims to gain a better understanding of the use and issues of CT in individual health assessment and to identify means to encourage more appropriate use of medical exposure to improve population health and well-being.


Constant innovation of health technology has expanded the applications of radiation in medical imaging and improved patient care. The justification of such exposures is based on the judgment that the clinical benefit of the medical imaging procedure will outweigh the radiation detriment.

The established scenario in many parts of the world for medical imaging involves a patient with signs and/or symptoms being referred to a radiological procedure. In this scenario, the healthcare service is provided for people with a clinical condition to determine the presence or absence of disease as a basis for making further treatment decisions. In this scenario, evidence-based imaging referral guidelines developed for a number of clinical conditions can support the justification process and enhance appropriateness of referrals by informing referrers and radiologists of the most appropriate examination.

The scenario is different when medical imaging is performed on apparently healthy people (i.e. asymptomatic people) to detect early disease or risk factors for disease. In this context, medical imaging may take place within a formal population screening program (e.g. national mammography screening programs) or as an individual health assessment.

The survey

The survey is designed in six sections and should take no more than 10 minutes to complete at this link: https://extranet.who.int/dataform/433935?lang=en .

We highly appreciate your contribution to this WHO global survey. Please complete not later than 21st October 2016.

The workshops in Rio

The results of this survey will contribute to the development of a conceptual framework to support justification in this practice.

Results will also be presented and discussed with family doctors at a workshop on “Justification of medical imaging and role of family doctors” jointly organized by WONCA, WHO, ISR and IAEA to be held at the WONCA World Conference 2016, Rio de Janeiro, Brazil, on Saturday 05/11/2016 between 08:00h and 11:00h (Room 212).

A related workshop being held in Rio which you may also be interested in is: "Education and training in radiation protection of family doctors"

Dr María del Rosario PEREZ
Scientist, Radiation Programme
Department of Public Health, Environmental and Social Determinants of Health (PHE)
Cluster of Family, Women’s and Children’s Health (FWC)
e-mail: perezm@who.int