Substituting proxy ratings for patient ratings in cancer clinical trials: an analysis based on a Southwest Oncology Group trial in patients with brain metastases.

摘要: In studies of the effect cancer treatment in advanced disease setting, researchers have attempted to avoid missing data for quality life (QOL) assessments by either substituting proxy patient from outset or interspersing measures when patients are unable respond. Although poor agreement between and has been amply demonstrated literature, interest using persists. Completion Spitzer QL-Index a small sample with brain metastases family member proxies provided evaluating ability substitute QOL assessments. These cannot address efficacy due modest size. Rather, analyses serve alert important distinction (in clinical trial setting) use as surrogate. We present several methods accuracy identifying other sources error bias that may vary time arm. Lin's concordance correlation coefficient suggests generally capturing patient's perspective his/her QOL. A longitudinal analysis rather than responses could lead different conclusions concerning radiation therapy's on