The authors of this review found that genetic counselling may have a positive impact on risk perception accuracy and recommended further research. The overall conclusion was cautious and the research recommendations appeared sound, but a number of limitations outlined should be borne in mind when reading the results of the study.

To review the effect of genetic counselling on risk perception accuracy

The authors searched PubMed, EMBASE, Web of Science, ERIC and PsycINFO databases for studies published in English in peer-reviewed journals between 2000 and February 2007. Searches were supplemented by use of Google Scholar to identify grey literature. Search terms were reported. A range of journals was handsearched (listed in the paper) from January 2000 until February 2007. Further key author and reference searches were conducted.

Randomised controlled trials (RCTs) and prospective studies were eligible for inclusion if they assessed the effect of genetic counselling on quantitative measures or risk perception accuracy linked to an objective risk estimate and focused on at-risk individuals rather than intermediaries. Two reviewers independently selected papers for the review.

Studies reported the percentage of patients within the defined category of accuracy or examined the degree of overestimation or underestimation of risk, or both. Assessments of risk perception accuracy were made immediately post-counselling, post-counselling (unspecified), one to seven days later or after three or six months. Most studies had similar content in terms of the counselling session.

The authors stated that they extracted quality characteristics from the included studies. No further details were provided.

Studies were extracted by two authors independently using standardised forms. Disagreements were resolved by consensus.

A narrative synthesis was conducted.

Differences in outcomes between studies were discussed with respect to the content of the counselling session.

Nineteen studies were included in the review (n=2,827): two RCTs and 17 prospective studies. Four studies mentioned using a genetic counselling protocol. two studies used a standardised counselling script and three studies used audiotapes to check session content; the other studies used none of these.

Overall, studies indicated that genetic counselling had a positive effect on risk perception accuracy. Some studies found no effect or detected an effect only for low-risk individuals.

Studies that assessed the proportion of participants who accurately estimated their risk showed an average increase in correct perceptions of approximately 25% (range 2% to 55%). An average of 42% of people estimated their risk correctly before counselling and an average of 58% did so after counselling. An average of 25% (range 5% to 76%) continued to overestimate risk and 19.5% (range 7% to 55%) continued to underestimate risk.

Studies that assessed changes in average overestimation of participants' perceived risk found an average overestimation of approximately 18% (range 6% to 40%) after counselling in comparison with 25% (range 11.5% to 42%) before counselling. Across the studies, average decrease in overestimation was approximately 8%.

Results that linked content of the sessions to risk perception accuracy gave mixed results.

Genetic counselling may have a positive impact on risk perception accuracy. Further research was recommended.

This review had defined inclusion criteria in relation to participants, intervention, outcomes and study designs. A range of databases and other sources were explored to locate studies. The restriction to English-language papers may have resulted in some studies being missed. A further problem was that studies published before 2000 were not included in the review and not all of these had been incorporated into the previous meta-analyses, which were restricted to breast cancer. Some methods for reduction in bias were reported for the review process, but it was unclear if and how study validity was assessed. No detail on the genetic conditions examined in each study was provided, so no differences in risk perception outcome related to condition could be ascertained. A narrative synthesis appeared appropriate given the variation between studies. Although the authors' overall conclusion was cautious and research recommendations appeared sound, the limitations outlined should be borne in mind when reading the results of the study.

Practice: The authors stated that genetic counsellors should discuss the role of family history and perform a family history assessment as recommended by National Society of Genetic Counselors (NSGC) Task Force. Counsellors were advised to present numerical risk estimates (using visual aids) before discussing the meaning of any risk estimates.

Research: The authors stated that future studies should link risk perception changes to objective risk figures to assess changes in risk perception accuracy. Future researchers should define risk perception accuracy as correct counselled risk and base their risk estimate on generally applied methods to allow for better comparison between studies. Use of both measures of risk perception accuracy (percentage of patients within the category of accuracy and decrease in overestimation of risk) was recommended. Future studies should describe session content in more detail and aim to determine the feature(s) of the counselling session that improved risk perception accuracy. The effect of genetic counselling for a wider variety of hereditary conditions should be examined.

Maastricht University.

Meiser B, Halliday JL. What is the impact of genetic counselling in women at increased risk of developing hereditary breast cancer? A meta-analytic review. Social Science and Medicine 2002; 54:1463-1470.

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.