Only around half of drivers comply with reduced speed signs and a quarter travel at more than 24mph following the implementation of lower limits, the research found.

However faster drivers reduce their speed more significantly following the introduction of 20mph signs, with the 85th percentile speed falling by 1.1mph in residential areas and by 1.6mph in city centres.

Road characteristics have a much larger impact on the speeds that drivers choose to adopt than whether there is a 30mph or 20mph limit, the study showed. Evidence also points to no significant change over the short term in collisions and casualties in the majority of cases where 20mph limits have been introduced; while journey times are estimated to have increased by between 3% and 5%.

There was, however, a small increase in the proportion of survey respondents to the 20mph research study who stated that they have increased their use of active travel modes. It was also said that 81% of cyclists and 75% of residents expressed post-implementation support for 20mph limits.

According to the survey, most resident drivers (72%) and non-resident drivers (69%) agreed that a 20mph limit in an area makes it more acceptable to drive at a lower speed. But a common area of concern across all user groups surveyed was around compliance, with most saying that stronger enforcement measures are needed for 20mph limits to be effective.

Parliamentary Advisory Council for Transport Safety executive director David Davies commented: “The findings of this study deserve to be taken very seriously. Many local authorities have been waiting for this report before deciding whether and how to implement local schemes.”

He added: “The changes resulting from 20mph limits are disappointing but not surprising. The study finds that signed only 20mph limits have very small effects on speed and, surprisingly, no effects on casualties.”

He called for the Government to review its guidance to councils on setting local speed limits in light of the report. “They must look again for practical, effective measures to reduce speeds and casualties.”

• Government has announced a package of 50 proposed measures to improve safety as part of a new two year action plan which aims to combat road rage, encourage greater mutual respect on the roads and protect the most vulnerable users.

Under the strategy councils will be given powers to tackle dangerous parking in cycle lanes, while being encouraged to spend 15% of their local transport infrastructure funding on walking and cycling.

The Department for Transport will also appoint a new cycling and walking champion and host a Bikeability Summit to encourage businesses to promote active travel to their employees.

(Photograph: Alastair Lloyd)