Further validation of Zagazig depression scale shortened form (ZDS-SF) and depression diagnosis in a United Kingdom (UK) student population

Abstract

The Zagazig Depression Scale has been validated in Egyptian populations and the shortened form 
(ZDS-SF) found high rates of depression in Egyptian students. Preliminary research has supported the 
validity and reliability of the measure in a UK student but further work is needed. The study aimed to 
determine the criterion validity of the ZDS-SF against a clinical interview and its test-retest reliability in 
a UK student sample. Participants (n=20) completed online measures of the Patient Health 
Questionnaire and the ZDS-SF at time 1. At time 2 (median follow-up 15 days) they were interviewed 
using the Clinical Assessment in Neuropsychiatry (SCAN) to establish a clinical diagnosis of 
depression, followed by re-administration of the online measures.  There was excellent (95%) 
agreement for diagnosis of depression between time 2 ZDS-SF and SCAN (Kappa = 0.89). The 
sensitivity of the ZDS-SF was 100% and the specificity 93.3%, giving an overall positive predictive value 
of 83.3%. The ZDS-SF symptom score also had good response stability over a two week interval (ICC = 
0.66). ZDS-SF scale is a valid measure of depression for use in a UK university student cohort with 
good psychometric properties and can be used for cross-cultural comparison studies.