Researchers from the London School of Economics (LSE) and University of Edinburgh said they used a "purpose-built barn" to measure navigation ability, speed and skills in following a pointed arm.
One of the tests involved the dogs, who were all from farms in Wales, finding their way to a food reward they could see but was behind a barrier.
Another involved offering two plates of food and measuring how quickly the dogs would go to the one with the bigger portion. They said that because "confounding" factors such as drinking, smoking and different socio-economic backgrounds did not apply, it was easier to measure differences in intelligence and links between longevity and intelligence than with humans. Dogs also develop dementia in similar ways to their human masters, the researchers said in a research paper published in Intelligence, meaning that the findings could be comparable to human beings.
"Even within one breed of dog... there is a variability in test scores. A dog that is fast and accurate at one task has a propensity to be fast and accurate at another," the researchers said.
This type of research "will provide crucial information on the relationship between intelligence and health, ageing and mortality," they added.
Rosalind Arden, a research associate at the LSE, said the research was "the first step in trying to develop a really snappy, reliable dog IQ test." Mark Adams, research fellow at the University of Edinburgh, said the research could be the foundation of a "dognitive epidemiology".
"Dogs are excellent for this kind of work because they are willing to participate and seem to enjoy taking part," he said.