The economic gap between Protestants and Catholics is greater in Scotland than it is in Northern Ireland, a new study has found.
The research has surprised academics and experts, who had assumed Catholics in the province faced greater disadvantage than their Scottish counterparts.
Now the Catholic Church in Scotland has called for more to be done to narrow the divide, which includes long-term unemployment, education, house ownership and mortality.
The report involved experts at Queen's and Ulster Universities and the University of Edinburgh.
They said initial analysis showed Catholic men in Scotland were 39% more likely to die between the ages of 25 and 74 than Protestants.
When the data was adjusted to take the effect of socio-economic status on death rates into account, the figure was revised to 14%; and with Scottish women it was 12%.
In Northern Ireland, Protestant men were almost 5% more likely to die aged between 25 and 74 than Catholics, and Protestant women about 1% more likely to die than Catholics.
The authors conclude the situation may have been caused in part because Scotland does not have specific legislation to tackle religious inequality introduced in Northern Ireland during the Troubles.
David Wright of Queen's, the lead author among the academics involved, admitted he and his colleagues had been surprised by the findings.
"Normally if you want to find a story about religion then you come to Northern Ireland, where we knew we would find a difference," he said.
"But we didn't really expect to find it in Scotland."
The study used a sample of 156,448 Scots and 248,255 people from Northern Ireland aged between 25 and 74 during the 2001 census, who were then observed over the following nearly seven years.
Researchers concluded that 20.9% of Scottish Catholics were in the professional class compared with 27.1% of Catholics here.
Some 10.2% of Scottish Catholics were long-term unemployed compared with 8.6% of Catholics here.
In education, just 14.2% of Scottish Catholics had a degree compared to 16.7% of Scottish Protestants. In Northern Ireland, the figures are 17% and 15.3% respectively.
More Scottish Catholics (35.7%) did not have a car, compared with 32% of Scottish Protestants. Here the corresponding figures were 17% of Catholics and 12.8% of Protestants.
More NI Catholics owned their own home (77.6%) compared to 66.2% in Scotland.
"These disadvantages (in Scotland) may result from sectarian discrimination acting on a much smaller minority group that is without the protection of the well-established anti-discrimination legislation enacted in Northern Ireland," the report said.