Patient self-reports of breast cancer treatments are sometimes used in the clinical care of survivors, and commonly used in survivorship research. Our results suggest that this may be particularly useful when the research investigation only requires general information about treatments received, as we found good concordance between medical records and patient reports of broad categories of treatments, consistent with prior studies [5,6,7,8,9,10]. However, accuracy of self-report of specific medications was imperfect even in those < 5 years from diagnosis, and even in this highly educated population who volunteered to participate in a web-based survey focused on recipients of chemotherapy. This is important for clinicians providing survivorship care to realize as it emphasizes the importance of obtaining medical record confirmation of patient-reported drug data. This also highlights the potential value of survivorship care plans as a mechanism to improve patient recall of treatments received and to enhance communication to future providers to inform clinical care (for example, if an otherwise healthy survivor is experiencing mild intermittent lower extremity edema, cardiac dysfunction will be lower on the differential diagnosis if it is known that a patient was not previously treated with a potentially cardiotoxic drug).
Importantly, our post-diagnosis median recall time (more than five years) was significantly longer than in most other studies. Given that breast cancer survivors are living longer as treatment advances improve cure rates, the demonstration of accurate recall over many years will be important for both clinical care and epidemiological studies focused on long term prognosis, side-effects, and quality of life metrics.
It is possible that discrepancies between patient-reports and medical records may be attributed to recall bias, question design, or missing information from the medical records. A prior study demonstrated lower rates of concordance when open-ended questions were utilized rather than prompts [8], so we provided a prompting list of common breast cancer drugs and combination regimens to aid recall. To the best of our knowledge, this is the first study that analyzed accuracy of self-report of breast cancer treatments utilizing an email request recruitment strategy and a web-based survey. While our study did not demonstrate an association between frequency of discrepancies and education level, our population was overall highly educated, likely at least in part due to our recruitment strategy through Army of Women and use of a web-based survey. Therefore, our results may not be generalizable to less educated individuals. In fact, a prior study performed in low-income women did demonstrate an association between decreased accuracy of self-reports and less education [7].
Other limitations include our relatively small sample size, the use of a single physician for medical record abstraction, and the inability to obtain medical records for all survey respondents. It is possible that discrepancy rates would have been different in those for whom medical records were not provided. We also did not collect medical records for patients who reported that they had not received chemotherapy because the other endpoints of our study (not presented in this manuscript) are related to chemotherapy toxicity, so we are not able to assess rates of underreporting for the yes vs. no chemotherapy variable.
In conclusion, highly-educated young women accurately recall receipt of broad categories of breast cancer treatment including systemic chemotherapy, targeted therapy, and hormonal therapy up to ten years after diagnosis. Therefore, the use of self-report may be an acceptable alternative to medical record abstraction in certain circumstances, but to provide optimal clinical care knowledge of specific medications received, self-report should still be confirmed by medical record review.
