Factor structure and validity of Type D personality scale among Indian (Tamil-speaking) patients with acute myocardial infarction

Background: Type D personality has been linked to negative outcomes following acute myocardial infarction (AMI). Our objective was to determine the factor structure, reliability, and validity of the Type D personality construct among people with AMI in the Indian clinical setting. Materials and Methods: In a cross-sectional study conducted between August 2016 and July 2017, 200 consecutive patients with AMI admitted to a tertiary care center completed the Tamil version of the Type D scale-14 (DS-14). The Eysenck Personality Questionnaire Revised-Short Form (EPQR-S) was also administered to check the convergent/divergent validity. Results: The prevalence of Type D personality was 24%. Results of the principal components analysis revealed a four-factor solution for the Tamil version of the DS-14 which explained more than 75% of the variability. Strong convergent validity with the neuroticism subscale of EPQR-S (r = 0.84, P < 0.001) and divergent validity with the extraversion subscale (r = −0.75, P < 0.001) was noted. The two subscales of the Type D scale, negative affectivity and social inhibition (SI), demonstrated good reliability (Cronbach's alpha of 0.85 and 0.76, respectively). Dropping item no 14 from the DS-14 led to significant increase in internal consistency (Cronbach's alpha 0.81) for the SI subconstruct. Conclusion: Among an Indian Tamil-speaking clinical sample of patients with AMI, Type D is a valid construct and can be assessed using the regional version of the DS-14 which showed a four-factor structure and good psychometric properties. Item no. 14 of the DS-14 scale may need modification for the Indian setting.