Background: Negative emotions, which have a common, chronic and recurrent structure, play a vital role in the development and maintenance of psychopathology. In this study, loneliness as a negative emotion was considered to be a predisposing factor in depression.
Aim: The aim of this meta-analysis is to determine the effect of loneliness on depression.
Method: Initially, a literature scan was performed and all related literature was pooled together ( n = 531). Based on scales determined by the researchers, it was decided to include 88 studies in the analysis. This study obtained a sampling group of 40,068 individuals.
Results: The results of using a random effects model for analysis showed that loneliness had a moderately significant effect on depression. None of the variables of study sampling group, type of publication and publication year were found to be moderator variables.
Conclusion: According to the results of the research, loneliness may be said to be a significant variable affecting depression. The findings obtained are discussed in light of the literature.
Keywords: Loneliness; depression; meta-analysis.