The Validity and Reliability of the WHO Schedules for Clinical Assessment in Neuropsychiatry (SCAN Thai Version): Anxiety Disorders Section
Thawatchai Krisanaprakornkit MD*, Poonsri Rangseekajee MD*, Suchat Paholpak MD*, Jiraporn Khiewyoo PhD**
Affiliation : * Department of Psychiatry, Faculty of Medicine, Khon Kaen University, Khon Kaen ** Department of Biostatistics and Demography, Faculty of Public Health, Khon Kaen University, Khon Kaen
Background : Anxiety disorders are some of the most prevalent psychiatric disorders, have early onset, are
chronic and can cause functional impairment. It is, therefore, crucial to establish an accurate diagnosis for
treatment and research purposes.
Objective : To test the validity and reliability of the W.H.O. Schedules for Clinical Assessment in Neuropsychia-
try (SCAN Thai Version): Anxiety Disorders Section.
Materials and Methods : The linguistic clarity of the psychiatric schedules for Thais was tested by psychiatrists
from the country’s four regions. The psychiatrists were competent in the use of the schedules and their under-
lying objectives. Then between October 2004 and August 2005, Reliability of SCAN: anxiety disorder section
was tested among 30 participants, including patients with anxiety disorders and normal volunteers.
Results : Based on reactions from Thais and consultations from competent psychiatrists, content validity was
established. The duration of interviews for anxiety disorders section averaged 45.1 min (SD = 13.5). The
reliability determined by Cohen’s kappa coefficient for the 83 items that related to anxiety disorders in the
SCAN were in Section 3, 4, 5. This overall inter-rater reliability was 0.79 (SD = 0.22), which were in substan-
tial level of agreement. The overall intra-rater reliability was rated by the same psychiatrist 2 weeks apart.
The result was 0.84 (SD = 0.21), which was near perfect agreement. There were three items (3.6%) of fair
agreement and five items (6%) of moderate agreement that were caused from discrepancy of item definitions
and the subjectivity of raters.
Conclusion : The Anxiety Disorders Sections of the WHO Schedules for Clinical Assessment in Neuropsychia-
try (SCAN Thai Version) were an effective tool for assessing symptoms of anxiety disorders among Thais.
Keywords : Semi-structured interview, Schedules for clinical assessment, Neuropsychiatry, Validity, Reliability, Anxiety disorders, Panic disorder, Phobic disorder, Obsessive-compulsive disorder, Generalized anxiety dis- order
