185perception or accuracy is more complicated and not always successful and is likely
further complicated by diversity in individuals’ health and social experiences”
(p. 299). Patients often have inaccurate perceptions of their genetic risk, and these
misperceptions often are not changed by genetic counseling. “For example, the cli-
ent may speak of undergoing a genetic test to ‘get some certainty’ despite the test
providing only an indication of risk (uncertainty) of developing cancer by a certain
age” (O’Doherty and Suthers 2007 , p. 410).
So how can you best present risk information? As percentages? Numbers? With
verbal descriptors? Does your patient have a 1 in 100 chance of having a genetic
condition or a 99 in 100 chance of not having it? There is no simple answer that fits
every patient and situation.
Hallowell et al. ( 1997 ) found a majority of their sample of genetic counseling
patients who received risk information concerning breast and ovarian cancer pre-
ferred quantitative data because these types of data provide clearer and more con-
crete information. The researchers found little difference in patient preference for
percentages, proportions, or population comparisons.
Although the basis of most risk communication in genetic counseling is quantita-
tive data, some patients prefer qualitative descriptions (e.g., the risk is high or low
or likely or unlikely). Thus, it can be helpful to include both quantitative and quali-
tative descriptions. But know that different people in different situations will attach
different meaning to risk information. For example, a couple may view a recurrence
risk of 1 in 4 or 25% as being low because they came in thinking their chance of
recurrence was 100%. Similarly, a relatively low numeric risk (like 3%) may be
perceived as insurmountable due to a devastating experience or perceived high bur-
den. You generally should avoid providing only qualitative data since they can be
misinterpreted by the patient and/or reflect your biases (Austin 2010 ; Melas et al.
2012 ; O’Doherty and Suthers 2007 ; Sagi et al. 1998 ).
Typically, in genetic counseling there are five types of quantitative formats for
providing risk information (Hallowell et al. 1997 ):
- Proportions (5 in 100 or 1 in 20)
- Percentages (5%)
- Ratios (1:20)
- Odds against (19 to 1)
- Comparisons with population risks (e.g., risk for breast cancer in women who
are carriers of BRCA mutation as compared to the population risk for breast
cancer).
Austin ( 2010 ) suggests framing risk as a combination of “numeric probability,
context, and nature of the potential outcome” (p. 229). She defines context as “factors
such as the client’s perceptions of illness etiology, family history, population preva-
lence of the condition”; the nature of potential outcome as “the perceived severity
(e.g. physical, emotional, financial impact) of illness for which numeric probability
is being provided”; and numeric probability as “the pre-existing subjective numeric
probability figure perceived by the client [that] may be modified by the objective
numeric probability provided by the counselor” (p. 229). She recommends (p. 231):
7.1 Communicating Information