Abstract
OBJECTIVES
To develop a simple screening scale to predict depression after discharge in patients with acute coronary syndrome after percutaneous coronary intervention (ACS-PCI) and to verify its reliability, validity and cutoff value.
DESIGN
Prospective longitudinal study was conducted 1 week and 3 months after discharge.
SETTING
Two hospitals where PCI is performed in Japan.
PARTICIPANTS
A total of 183 patients were potential candidates for the survey, of whom 42 provided valid responses (response rate: 23.0%).
RESULTS
The number of items was reduced from 14 to 12 with item-total correlations and principal component analysis. Cronbach's alpha coefficient was 0.832 and the intraclass correlation coefficient (1, 2) was 0.811 (95% CI 0.650 to 0.898). Significant correlations were observed for concurrent validity (r=0.699, p<0.01) and predictive validity (ρ=0.538, p<0.01). The area under the receiver operating characteristic curve was 0.799 (CI 0.629 to 0.970). A cut-off value of 28 points was obtained from the Youden index and demonstrated a sensitivity of 1.000, specificity of 0.553, positive predictive value (PPV) of 0.190 and negative predictive value of 0.000.
CONCLUSIONS
This study developed a simple screening scale for predicting postdischarge depression in patients with ACS-PCI (SDACS-12) and demonstrated its reliability, validity and predictive ability with 12 items. Nevertheless, its results should be interpreted cautiously given the moderate variance explained by PCA and the low specificity and PPV.