This survey of FPs from rural, suburban, and urban BC demonstrates that their tested knowledge of palliative radiotherapy indications is correlated with their self-assessed knowledge of palliative radiotherapy. It also demonstrated that FPs undervalue the role of palliative RT beyond the obvious circumstance of painful bone metastases, mirroring the knowledge gap found in US palliative care physicians. Scores on tests of indications for palliative RT, and self-assessed knowledge of palliative RT, are higher in those with prior training in radiotherapy or palliative care. Furthermore, knowledge (both self-assessed and tested) of palliative radiotherapy is highly correlated with referral for RT. Though the retrospective nature of this study cannot assess causality, these results support further research assessing whether improved FP education in palliative RT will increase utilization of this treatment, with a potential to improve the quality of life of patients with metastatic cancer.
There are several potential explanations for the relationship seen between knowledge of palliative RT and referral for RT. The most plausible explanation is that formal education in palliative RT indications results in improved knowledge of indications for palliative RT, and in turn results in increased referral for RT. Second, the causality may be reversed; FPs who have encountered patients with metastatic cancer and referred for palliative RT have improved knowledge of RT indications as result, potentially through reading motivated by the patient encounter or education received from radiation oncologist consultation letters. Third, there may not be a causal relationship between knowledge and referral for RT, but rather both knowledge and referral may be correlated to an unmeasured factor, such as patient volume. Likely, the relationship identified in this study is a combination of all of these explanations, though the nature of this study design does not allow for assessment of causality.
Given the relationship seen between FP knowledge of palliative RT and referral for palliative RT in both this and other studies, future research should assess whether educational interventions aimed at FPs improve referral and utilization of palliative RT. Given the high scores on the analgesic compared to haemostatic properties of RT observed, it would potentially be more beneficial to focus on improvement in education of less well known palliative RT indications such as bleeding, rather than commonly known indications such as painful bone metastases. However, given that the response rate to our survey is only 33%, we are unable to assess the knowledge of the remaining 67% of physicians, whose knowledge may have an impact on the overall rate of referral for palliative RT. Certainly, education on common indications for palliative RT is important and necessary, and therefore should not be omitted . Furthermore, these results suggest that FPs in practice, rather than medical students, may be the more appropriate target audience for future studies.
There are several potential methods to improve education and potentially the utilization of palliative RT. Conventional methods aimed at medical students or FPs through continuing medical education sessions, whether virtual or in-person have been assessed in multiple medical fields . Several authors have reported on education of medical students, showing short term improvements in knowledge, with limited evidence to date that this will translate into long term practice changes for those who choose FP [20–23]. Dennis and Duncan have recommended that educational interventions for medical students should focus on general knowledge that is applicable to future FPs, rather than detailed information more relevant to oncologists . More novel techniques to both educate and improve appropriate referral to specialists have also been developed. For example, in BC a “shared care” initiative is currently under investigation where both FP and specialists are compensated for telephone advice on the appropriate management and referral of patients [24, 25].
The results of this research should be considered in the context of its strengths and limitations. The reasonable response rate and equal proportions of FPs from rural/suburban versus urban/metropolitan areas improves the generalizability of the results. Given the BCCA was the sole provider of RT, in a jurisdiction with universally publicly funded health care and salaried radiation oncologists, referrals are not influenced by competition between RT providers or compensation of FPs or radiation oncologists. The assessment of knowledge of palliative RT indications is limited by the fact that the investigators interpreted respondents’ answer of “somewhat” or “very effective” as a respondent’s belief that RT was indicated in that scenario, since indication for RT was not directly asked. Also, the nature of the survey study design limits several interpretations of the results. First, causality between knowledge and referral for palliative RT cannot be assessed. Second, survey research is prone to response bias, where respondents with certain characteristics (such as interest in oncology) may be more likely to return surveys, and thereby result in higher mean tested and self-assessed knowledge scores than may exist in the true population . Third, recall bias is common in survey research, and for this study theoretically could result in an under-reporting of previous referral for RT . However, many of these limitations are common to all survey research, and the effort placed to sample FPs from rural through metropolitan practices broadens the generalizability in comparison to most survey research which focuses on academic physicians.