Expanding access to BRCA1/2 genetic counseling with telephone delivery: a cluster randomized trial

Abstract

Background: The growing demand for cancer genetic services underscores the need to consider approaches that enhance access and efficiency of genetic counseling. Telephone delivery of cancer genetic services may improve access to these services for individuals experiencing geographic (rural areas) and structural (travel time, transportation, childcare) barriers to access.

Methods: This cluster-randomized clinical trial used population-based sampling of women at risk for BRCA1/2 mutations to compare telephone and in-person counseling for: 1) equivalency of testing uptake and 2) noninferiority of changes in psychosocial measures. Women 25 to 74 years of age with personal or family histories of breast or ovarian cancer and who were able to travel to one of 14 outreach clinics were invited to participate. Randomization was by family. Assessments were conducted at baseline one week after pretest and post-test counseling and at six months. Of the 988 women randomly assigned, 901 completed a follow-up assessment. Cluster bootstrap methods were used to estimate the 95% confidence interval (CI) for the difference between test uptake proportions, using a 10% equivalency margin. Differences in psychosocial outcomes for determining noninferiority were estimated using linear models together with one-sided 97.5% bootstrap CIs.

Results: Uptake of BRCA1/2 testing was lower following telephone (21.8%) than in-person counseling (31.8%, difference = 10.2%, 95% CI = 3.9% to 16.3%; after imputation of missing data: difference = 9.2%, 95% CI = -0.1% to 24.6%). Telephone counseling fulfilled the criteria for noninferiority to in-person counseling for all measures.

Conclusions: BRCA1/2 telephone counseling, although leading to lower testing uptake, appears to be safe and as effective as in-person counseling with regard to minimizing adverse psychological reactions, promoting informed decision making, and delivering patient-centered communication for both rural and urban women.

© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Figures

Figure 1.

Consolidated Standards of Reporting Trials (CONSORT) flowchart. * Seven families had at least one member randomized and one member not randomized. † N depends on completion of intervention and completion of measure (see Table 5). ‡ Intent-to-treat refers to data analysis after imputation of unknown testing uptake. GC = genetic counseling. HBOC = hereditary breast and ovarian cancer.

Figure 2.

Effects and noninferiority ranges one week after pretest counseling and six months after the last intervention. The between-group intervention differences were estimated using linear models together with one-sided 97.5% cluster bootstrap confidence intervals. One-sided 97.5% confidence intervals were used, because the goal was to test if telephone counseling was not unacceptably worse than in-person counseling. IP-GC = in-person genetic counseling; TEL-GC = telephone genetic counseling.

Figure 3.

Effects and noninferiority ranges one week after post-test counseling for women who were tested. The between-group intervention differences were estimated using linear models together with one-sided 97.5% cluster bootstrap confidence intervals. One-sided 97.5% confidence intervals were used because the goal was to test if telephone counseling was not unacceptably worse than in-person counseling. IP-GC = in-person genetic counseling; TEL-GC = telephone genetic counseling.