Background: Evidence suggests that Deaf people may have a greater prevalence of depressive symptoms. However, it is unclear whether commonly used written screening instruments are accurate with this population because of their unique cultural and linguistic factors.
Setting: Deaf persons (n = 71) residing in southeastern Michigan.
Methods: Subjects completed the Zung Self-Rated Depression Scale in both the written (ZSDS-W) and American Sign Language (ZSDS-S) formats and the Hamilton Depression Scale (HAM-D) in American Sign Language in counterbalanced order, followed by a Test Of Reading Comprehension (TORC). They also provided extensive data on demographic, hearing loss, language use, social and health care use variables.
Results: Mean subject age was 52 years, 63% of subjects were women, 95% were Caucasian, and 47% were married (87% to another deaf/hard of hearing person). Thirty percent had a college degree and 20% had less than a 10th grade education. The ZSDS-W and ZSDS-S scores were highly correlated (r = +0.79), although the mean ZSDS-W score was 2.8 points higher (P = .001). The ZSDS-S correlated more highly (r = 0.80) with the HAM-D than the ZSDS-W (r = 0.71). There was a significant interaction effect (P < .001) such that the ZSDS-W and HAM-D were significantly associated among higher literacy subjects (beta = 0.80, P < .001) but not lower literacy subjects (beta = 0.20, P = .183). There were no other significant associations between depression scores and numerous demographic, educational, hearing loss, social or language variables.
Conclusions: Compared with the conventional ZSDS-W, the ZSDS-S more accurately assesses depression severity among deaf persons with lower English literacy. However, given the greater sensitivity of the ZSDS-W and the practical barriers to ZSDS-S in physician practices, further research should determine which modality is best for routine depression screening.