Measurement issues in the evaluation of experimental treatment interventions.

The final discussion of followup measurement highlights earlier discussions of patient and treatment measurement. Followup is the best assessment of the efficacy of a treatment intervention. Therefore, it is critical to have a clear set of baseline measures on the patient in those areas that are expected to be able to improve with the intervention and to repeat these measures at followup to assess improvement and outcome. The measures that are collected at followup are essentially identical to the measures that were collected at the time of treatment admission but in abbreviated form. However, the same methodological issues, techniques, and considerations apply. As at the time of the initial assessment, the patient should be measured in all those areas that are expected to be changed, the patient should be assessed with multiple methods (interview questionnaire and objective laboratory data), and all care should be taken to assure the patient that the information will be treated in a professional manner and that her privacy and confidentiality will be protected. An effective posttreatment evaluation requires effective tracking, locating, and reinterviewing each patient following treatment. The ability to recontact these patients after treatment is almost entirely dependent on the level of information, patient preparation, and interagency cooperation established during the time the patient was in treatment. Followup is an important but difficult job that must be coordinated from the very start of treatment and must involve the patient, followup staff, clinical program, and sponsoring agency or agencies.