Official statistics allowing comparisons of death rates between cities and states did not exist.
The 15-year follow-up found little difference in death rates between men screened annually and those in the control group, who were screened occasionally.
The American study showed no statistical difference in prostate cancer death rates between a group of men who had the screening and a control group who did not.
Smoking is the single biggest cause of inequalities in death rates between the richest and poorest in our communities". How true.
Researchers found that Britain had achieved a 63percentnt reduction in age-standardised cardiovascular disease death rates between 1989-91 and 2013-15.
There was no overall difference in death rates between patients on canakinumab and those given placebo injections, and the drug did not change cholesterol levels.
Last week, Danish experts cast doubt on the benefits of mammography, saying there were few differences in death rates between women who are screened and those who are not screened.
But now, 11 years later, the study investigators, led by Dr. David B. Thomas of the Fred Hutchinson Cancer Research Center in Seattle, report that there was no difference in the death rates between the two groups.
"The large variations in death rates between European countries have reduced since the 1990s when there was a threefold variation across Europe from 3.6 per 100,000 in Portugal to 9.3 in Denmark," he said.
Their study, published in the Journal of Epidemiology and Community Health, examined fluctuations in weather patterns and death rates between 1993 and 2006 to characterise the associations between temperature and mortality.
In the case of England the increase in inequality for death rates between the top and bottom quintiles was statistically significant, in that there was no overlap between the 95% confidence interval ranges for each five year period.
