The International Statistical Classification of Diseases and Related Health Problems (ICD) is the foundation for the identification of health trends and statistics globally, and the international standard for reporting diseases and health conditions. It is the diagnostic classification standard for all clinical and research purposes. ICD defines the universe of diseases, disorders, injuries and other related health conditions, listed in a comprehensive, hierarchical fashion that allows for:

• easy storage, retrieval and analysis of health information for evidenced-based decision-making;
• sharing and comparing health information between hospitals, regions, settings and countries; and
• data comparisons in the same location across different time periods.

Note:  A version of ICD-11 was released on 18 June 2018 to allow Member States to prepare for implementation, including translating ICD into their national languages. ICD-11 will be submitted to the 144th Executive Board Meeting in January 2019 and the Seventy-second World Health Assembly in May 2019 and, following endorsement, Member States will start reporting using ICD-11 on 1 January 2022.

Post-traumatic stress disorder (PTSD)

Post-traumatic stress disorder (PTSD) is a syndrome that develops following exposure to an extremely threatening or horrific event or series of events that is characterized by all of the following:

1) re-experiencing the traumatic event or events in the present in the form of vivid intrusive memories, flashbacks, or nightmares, which are typically accompanied by strong and overwhelming emotions such as fear or horror and strong physical sensations, or feelings of being overwhelmed or immersed in the same intense emotions that were experienced during the traumatic event;

2) avoidance of thoughts and memories of the event or events, or avoidance of activities, situations, or people reminiscent of the event or events; and

3) persistent perceptions of heightened current threat, for example as indicated by hypervigilance or an enhanced startle reaction to stimuli such as unexpected noises. The symptoms must persist for at least several weeks and cause significant impairment in personal, family, social, educational, occupational or other important areas of functioning.

Source:  ICD-11 for Mortality and Morbidity Statistics (2018). 6B40 Post-Traumatic Stress Disorder  https://icd.who.int/browse11/l-m/en#/http%3a%2f%2fid.who.int%2ficd%2fentity%2f2070699808

Complex post-traumatic stress disorder (CPTSD)

Complex post-traumatic stress disorder (Complex PTSD) is a disorder that may develop following exposure to an event or series of events of an extremely threatening or horrific nature, most commonly prolonged or repetitive events from which escape is difficult or impossible (e.g., torture, slavery, genocide campaigns, prolonged domestic violence, repeated childhood sexual or physical abuse). The disorder is characterized by the core symptoms of PTSD; that is, all diagnostic requirements for PTSD have been met at some point during the course of the disorder.

In addition, Complex PTSD is characterized by

1) severe and pervasive problems in affect regulation;

2) persistent beliefs about oneself as diminished, defeated or worthless, accompanied by deep and pervasive feelings of shame, guilt or failure related to the traumatic event; and

3) persistent difficulties in sustaining relationships and in feeling close to others. The disturbance causes significant impairment in personal, family, social, educational, occupational or other important areas of functioning.

Source:  ICD-11 for Mortality and Morbidity Statistics (2018). 6B40 Complex Post-Traumatic Stress Disorder  https://icd.who.int/browse11/l-m/en#/http%3a%2f%2fid.who.int%2ficd%2fentity%2f585833559