Disorders specifically associated with stress: A case-controlled field study for ICD-11 mental and behavioural disorders

Abstract

As part of the development of the Eleventh Revision of International Classification of Diseases and Related Health Problems (ICD-11), the World Health Organization Department of Mental Health and Substance Abuse is conducting a series of case-controlled field studies using a new and powerful method to test the application by clinicians of the proposed ICD-11 diagnostic guidelines for mental and behavioural disorders. This article describes the case-controlled field study for Disorders Specifically Associated with Stress. Using a vignette-based experimental methodology, 1,738 international mental health professionals diagnosed standardized cases designed to test key differences between the proposed diagnostic guidelines for ICD-11 and corresponding guidelines for ICD-10. Across eight comparisons, several proposed changes for ICD-11, including the addition of Complex PTSD and Prolonged Grief Disorder, produced significantly improved diagnostic decisions and clearer application of diagnostic guidelines compared to ICD-10. However, several key areas were also identified, such as the description of the diagnostic requirement of re-experiencing in PTSD, in which the guidelines were not consistently applied as intended. These results informed specific revisions to improve the clarity of the proposed ICD-11 diagnostic guidelines. The next step will be to further test these guidelines in clinic-based studies using real patients in relevant settings.

Keywords: Experiment; Field study; ICD-11; PTSD; Vignette.

Figure 1

Percentages of diagnostic choices for Comparison 1: Do clinicians appropriately recognize the required symptom of re-experiencing and apply it correctly as a diagnostic requirement for the ICD-11 diagnosis of PTSD? Note: Correct diagnoses are in Table 3.

Figure 2

Percentages of diagnostic choices for Comparison 2: Do clinicians appropriately recognize functional impairment and apply it correctly as a diagnostic requirement for the ICD-11 diagnosis of PTSD? Note: Correct diagnoses are in Table 3.

Figure 3

Percentages of diagnostic choices for Comparison 3: Do clinicians appropriately base the ICD-11 diagnosis of PTSD on the presence of the required core symptoms, or do they tend to over-diagnose PTSD based on a history of specific types of stressors? Note: Correct diagnoses are in Table 3.

Figure 4

Percentages of diagnostic choices for Comparison 4: Can clinicians differentiate the proposed ICD-11 diagnostic requirements of Complex PTSD from those of PTSD? Note: Correct diagnoses are in Table 3.

Figure 5

Percentages of diagnostic choices for Comparison 5: Do clinicians inappropriately diagnose Complex PTSD based on a history of a severe and long-lasting stressor rather based on the required symptoms? Note: Correct diagnoses are in Table 3.

Figure 6

Percentages of diagnostic choices for Comparison 7: Do clinicians appropriately differentiate PTSD from Adjustment Disorder based on the required symptoms, or do they tend to inappropriately base this distinction on the nature of the stressor? Note: Correct diagnoses are in Table 3.

Figure 7

Percentages of diagnostic choices for Comparison 8: Do clinicians appropriately exclude diagnoses of Adjustment Disorder that do not evidence preoccupation and functional impairment as required by proposed ICD-11 guidelines? Note: Correct diagnoses are in Table 3.