This study was stimulated by the recent publication (Health Commun 2006;19(2):133–142) who reported the effects of insightful disclosure on outcomes in' peer-led internet breast cancer support groups. The present study attempted to replicate their hypotheses using the same methods for coding insightful disclosure as well as parallel outcome measures. Four hypotheses are tested; writing a higher percentage of insightful disclosure words will be associated with: (1) fewer BC concerns; (2) reduction in the emotional distress; (3) better physical health; and (4) few functional limitations. New members (N = 77) to BC bulletin boards (BB) were recruited through BB postings and/or e-mails. We asked them to fill out questionnaires measuring depression and quality of life, when they joined the BB, and again six months later. Two questionnaires (CESD and FACTB [Functional Well being, Physical well being, and Breast cancer Concerns]) were administered and repeated six months later. For two of the four outcome measures (Functional Well being and Breast Cancer Concerns), insightful disclosure played a crucial and significant role, the other two showed a trend toward significance (CESD and Physical well being). The three control variables, stages, years of cancer and level of participation all had effects on the outcomes, varying with the type of outcome measure. The findings, in this study, support Shaw et al. hypotheses. In their study, only one outcome measure, reduction of emotional distress was significant. Copyright © 2007 John Wiley & Sons, Ltd.