STRUCTURAL EQUATION MODELLING OF DEPRESSION ON QUALITY OF LIFE OF ADOLESCENTS

Abstract

Childhood and adolescent depression is common and often persists into adulthood. It negatively influences the development of youths, their school performance and can significantly increase the risk of substance abuse and suicide. It is the fourth leading cause of disease burden. Although childhood and adolescent depression is common and persist to adulthood, less work has been done in this area. This study assessed the effect of child depression on quality of life of adolescents in a resource constrained setting using structural equation model. Self-administered questionnaires, with questions assessing depression and quality of Life, were given to adolescents aged 10-19 years who consented to participate in the study. An Exploratory Factor analysis (EFA) was conducted to study the underlying factor structure in the instruments Child Depression inventory and World Health Organisation Quality of Life BREF (the CDI and QOL respectively). Subsequently, a Confirmatory Factor analysis (CF A) was done to assess adequacy of the factor structure in the EFA. The new model (from the CFA and EFA), referred to as the hypothesized model was compared with theoretical models to determine which was more adequate. A structural equation model was fitted using the AMOS (an extension of the SPSS) software to study the relationship between depression and Quality of Life. All hypothesis were tested at 5% level of significance. The CDI reported a 2-factor structure, while the adapted WHOQOL-BREF reported a 3 factor structure. The Root Square Mean Error of Approximation (RMSEA) for the 2 factor structure of the CDI was significant (0.044). In a similar way, the 3 factor structure of the WHOQOL-BREF had a significant RMSEA (0.047). Other fit indices also showed that the new hypothesized models had a better fit than the theoretical models in the CF A conducted. The overall reliability of both instruments were high (CDI:a= 0.84 and QOL:a= 0.847), however, the Cronbach's alpha for one of the Sub scales of the WHOQOL-BREF was low (0.08). The regression coefficient for the effect of child depression on quality of life was negative (-0.048). Conclusion: The Structural equation model fitted showed that Depression in non-clinical, general population of Adolescents is a poor predictor of quality of life. The CDI (used in assessing childhood depression) had a 2-factor structure in a non-clinical general population of adolescents. Similarly, the adapted WHOQoL BREF had a 3-factor structure. Theorectical models proposed by previous authors for the relationship between depression and quality of life were not identified by this study.