Methods for locating missing patients for the purpose of long-term clinical studies

The need for long-term follow-up studies in the evaluation of medical care is not unique to the field of orthopaedic surgery. Medical treatment is continuously changing, and there is pressure from many sources to make it more effective and cost-efficient. The impact that these factors will have on the lives of patients cannot be determined without investigative outcome studies. In order for those data to be meaningful, every reasonable effort should be made to obtain information on all patients in a study. Longitudinal studies require continued contact and evaluation of patients for many years after the administration of treatment. When planning a clinical study, the investigator should include the expense of locating patients in the estimates of the study costs, regardless of whether the study is prospective.