The Chinese version of the Davidson Trauma Scale (DTS-C) was developed to 
respond to the need of Chinese-speaking individuals. The DTS is a validated 
self-rating scale used in the diagnosis of posttraumatic stress disorder (PTSD). 
The DTS-C is translated from DTS through a two-stage translation. Subjects were 
drawn from a sample of 210 survivors of the 21 September 1999, Chi-Chi 
Earthquake. The scale showed good internal consistency (Cronbach's alpha = 0.97) 
and test-retest reliability (r = 0.88). Concurrent validity was obtained against 
the clinical diagnostic interview, with a diagnostic accuracy of 0.85 at DTS-C 
score of 44. It showed that the sensitivity was 0.9, specificity 0.81, positive 
likelihood ratio 4.74, and negative likelihood ratio 0.12. The recommended 
stratum-specific likelihood ratios were 0.10 (95% CI: 0.05-0.20) for the score 
range 0-39, 4 (2.22-7.23) for the score range of 40-59, and 6.14 (3.42-11.02) 
for the scores above 60. In PTSD diagnosed subjects, the factor structures 
closely resembled the DSM-IV grouping of PTSD symptoms. The psychometric 
strength of DTS-C is reliable for its future use, particularly for screening for 
subjects with possible diagnosis of PTSD.