The study looked at how the cost of borrowing for heavily indebted European countries is affected by the relationship between credit default swaps (CDS) and bond spreads. They found that during economic turbulence, CDS spreads can lead to increases in bond spreads in Portugal, Greece, and Spain. In Italy, there is a two-way relationship between CDS and bond spreads, but it's unclear which market leads. This means that changes in CDS spreads can directly impact how much it costs these countries to borrow money.