The cities of Beijing, Mexico City and Johannesburg are the most painful cities for commuters with the worst traffic in the world, according to a study.

The IBM Global Commuter Pain Study, which surveyed 8,192 motorists in 20 cities on six continents, claims drivers in Moscow face an average delay of two-and-a-half hours of traffic jams.

The study reflects the failure of transportation infrastructure to keep pace with economic activity and reports that traffic has gotten worse in the past three years in key international cities.

It also said roadway traffic in New Delhi and Beijing have affected health and school performance the most among the cities studied.

Stockholm has the least painful commute followed by Melbourne, Houston and New York City, the study said.

IBM compiled the results of the survey into an index that observed ten issues covering commuting time, time stuck in traffic, worsening traffic, high gas price, start-stop traffic, driving stress, road rage, traffic affecting work, stopped traffic, and traffic causing drivers to abandon trips.