Pucher's various transnational studies of bicycle transportation lead him to conclude that "the overwhelming evidence is that cycling is much safer and more popular precisely in those countries where bikeways, bike lanes, special intersection modifications, and priority traffic signals are the key to their bicycling policies." The authors of a 2009 meta-study on cycle infrastructure safety research at the University of British Columbia similarly conclude that "in comparison to cycling on bicycle-specific infrastructure (paths, lanes, routes), on-road cycling appears to be less safe."