Abstract
This study combined direct observation of seat belt use with interview methods to identify factors related to seat belt use in a state with a mandatory seat belt use law. Trained observers recorded restraint use for a probability sample of motorists travelling on roads throughout the State of Michigan. Roadside interviews of 1,864 drivers measured sociodemographic, situational, attitudinal, normative, and behavioural characteristics related to seat belt use. Selected sociodemographic characteristics which are not susceptible to change, as well as crash experience and safety attitudes that are difficult to modify, were related to belt use.