RACIAL DIFFERENCES IN TREATMENT PREFERENCES AFTER USING A LOW VERSUS HIGH LITERACY PROSTATE CANCER DECISION AID

Purpose: Research has shown that racial minorities often have different treatment preferences than Whites.  One question is whether this is the result of knowledge deficits, differences in literacy or numeracy levels, or any of a number of factors.  In the present research, men receiving prostate cancer biopsies were given either a low or high literacy decision aid (DA), and then treatment preferences were assessed.  The purpose of the present research was to explore racial differences in treatment preferences following exposure to low versus high literacy DAs. 

Method: 1023 men from four VA hospitals were recruited at their prostate cancer biopsy appointment; 77% of the participants were White, and 23% were non-White (of which 92% were African American).  At Time 1 participants were randomly assigned to receive either a low or high literacy prostate cancer decision aid.  Literacy (using the REALM), and subjective numeracy were also assessed.   At Time 2, which occurred after participants read the DA but just prior to receiving a prostate cancer diagnosis, men were asked to report their treatment preferences by indicating whether they were considering each treatment option.  Knowledge about the treatment options was also assessed.

Result:  Across both DAs, more White men were interested in active surveillance (41%) than non-White men (23%).  However this effect was moderated by the type of DA, B=1.40, SE=.37, p=.02:  Relative to the high literacy DA, the low literacy DA increased interest in active surveillance for Whites but not non-Whites. The low literacy DA also decreased interest in external beam radiation for Whites but not non-Whites, B=-1.29, SE=.55, p=.02. These interactions were still significant when controlling for numeracy, literacy, and knowledge.  There were no effects involving race for interest in any other treatment option (i.e., surgery, brachytherapy).

Conclusion:  Results showed that White men’s preferences were influenced by the low literacy DA, but the preferences of non-White men stayed the same regardless of the DA type.  Moreover, the effect of the different DAs did not change when controlling for numeracy, literacy, or knowledge.  These results suggest that Whites may be more likely to change their treatment preferences in response to a lower-literacy DA, but the treatment preferences of racial minorities are rooted in other factors that were not identified from the current analysis.