ESTIMATING THE PREVALENCE OF HARD-TO-REACH POPULATIONS - THE ILLUSTRATION OF MARK-RECAPTURE METHODS IN THE STUDY OF HOMELESSNESS

This paper assesses the potential of mark-recapture methods as a relat ively powerful innovative research method for estimating the prevalenc e of ''hard-to-reach'' human populations in the social welfare field. We outline the development of mark-recapture methods, illustrating som e recent applications. The body of the paper reviews the main methodol ogical and practical questions raised by the method. We suggest, by wa y of illustration, how it might be applied to estimating the prevalenc e of rough sleepers in a given geographical region.