J. Bernhard et al., QUALITY-OF-LIFE ASSESSMENT IN INTERNATIONAL BREAST-CANCER STUDY-GROUP(IBCSG) TRIALS - PRACTICAL ISSUES AND FACTORS ASSOCIATED WITH MISSINGDATA, Statistics in medicine, 17(5-7), 1998, pp. 587-601
We report on our experience of quality of life (QL) assessment in adju
vant clinical trials of the International Breast Cancer Study Group (I
BCSG), with special emphasis on cultural and logistical aspects of int
ernational organization that are unique to this group. Data are presen
ted regarding submission rates of assessments before and after treatme
nt failure, and timing of assessments relative to chemotherapy adminis
tration. To identify areas where rates might be improved, we investiga
ted the association between missing data and sociodemographic and biom
edical factors, treatment assignment, institution, chemotherapy compli
ance and toxicity in a trial of adjuvant chemoendocrine therapy for po
st-menopausal patients with breast cancer (IBCSG VII). The factors mos
t highly associated with missing data were institution and chemotherap
y compliance. (C) 1998 John Wiley & Sons, Ltd.