People from higher-income groups are more likely to leave their cars at home if they find their neighbourhoods attractive, a new study has found.

Lower- and middle-income residents who live in denser neighbourhoods – with stores, libraries and other destinations within easy reach – are more likely to walk or bike, researchers said.

However, neighbourhood density did not motivate higher-income residents to leave their cars at home.

Of the environmental factors studied, the only one that influenced how frequently the group walked or biked was how attractive they found their neighbourhoods to be.

Dimensions of "attractiveness" that motivated the higher-income group included seeing other people when they walk in their neighbourhoods, the attractiveness of buildings and homes and having interesting things to look at.

The findings are based on a random survey of 547 households in King County in US in the highest- and lowest-density neighbourhoods.

The survey, which was conducted in 2013, asked more than 100 detailed questions about people’s travel habits and about the built environment near their homes.

The median annual income range for the lower-income group was between USD 40,000 and USD 60,000, and for the higher-income group was above USD 140,000.

The factors significantly associated with an increase in how often people in the lower-income households biked or walked in a week were higher neighbourhood density, easy access to destinations, a younger average household age, having access to more bicycles and owning fewer cars.

"For the higher-income people, walking and biking is a largely result of choice, and our models show that the density of their neighbourhoods and most other things in their built environment, such as the accessibility of destinations, don’t really matter as much to them," said senior author Cynthia Chen, associate professor at University of Washington.

"For the lower-income group, walking and cycling appears to be the result of constraints, in which case higher neighbourhood density and easy access to destinations are positively associated with more walking or biking," she said.

The number of bicycles in the household was the only factor associated with more walking and biking trips in both income groups.

Each additional bicycle was related to 1.1 and 1.2 more days that someone walked or biked in the last week for the lower-income group and the higher-income group, respectively.

Access to each additional vehicle in a household is negatively associated with the number of days that the lower-income group walked or biked in a week – reducing that number by 2.5 days.

By contrast, the number of vehicles owned did not matter for the higher-income group.

People in the lower income groups were more likely to walk or cycle to get to their daily activities, while the rich were more likely to make these trips for exercise or recreation, the researchers said.