time–location sampling
a method of finding research participants in which members of a hard-to-reach target population (e.g., homeless persons, migrant workers) are recruited from specific locations at which they may be found during specific time periods. The sample is selected in stages: (a) the sampling frame is determined, comprising all of the locations at which there is sufficient attendance by persons in the population of interest to make sampling worthwhile; (b) a random sample of locations is chosen from this frame; and (c) a sample of participants is chosen, usually randomly, during each sampling event. Also called venue sampling.