The moderated mediation role of the extension in the relationship between union density and bargaining coverage

In some developed countries with lower union density, bargaining coverage becomes almost universal through the extension of a collective agreement beyond union members to non-unionised employees. However, such extensions are criticised for creating a negative incentive for union membership, undermining the independence of unions vis-a-vis the state and distorting competition in the market. The current study presents a moderated mediation analysis to examine the relationship between union density and bargaining coverage through the bargaining level, using data from the OECD/AIAS’s ICTWSS. Empirical results confirm that the extension has a positive moderated mediation impact on the link between union density and bargaining coverage with an indirect effect of bargaining level. Also, the conditional direct effect of the extension negatively interacts with the association between union density and bargaining coverage, while the conditional indirect effect of the extension positively moderates their relationship through the centralised bargaining level.