Surveying Hard-to-Reach Groups

Surveying hard-to-reach groups is difficult but necessary to prevent selection effects and biased sampling. Their diversity makes it difficult to recommend efficient solutions because they bring challenges that are specific to each group. Among these are limited ability in official languages, literacy problems, physical or mental disabilities or the particularities of subgroups such as ethnic, religious and cultural minorities, adolescents and the elderly. Drawing notably on lessons from migration research, this paper reviews the contemporary issues associated with five sets of circumstances that may result in groups being unreached by transport surveys.