This study applied the TDF to help understand factors that influenced chiropractors’ adherence to radiographic guidelines for LBP and their imaging ordering behaviours. Results from focus groups with chiropractors in NL showed that the main factors influencing their adherence to radiographic guidelines and LBP imaging ordering behaviours could be coded into six key domains: Knowledge; Skills; Social/professional role and identity; Beliefs about consequences; Memory, attention, and decision processes; and Behavioural regulation. Many of these factors were enablers to guideline adherence and potentially reduced the ordering of non-indicated imaging for LBP.
In our current study, there were varied levels of knowledge and awareness of radiographic guidelines, with some chiropractors being able to state specific guidelines, and others not being aware of guidelines at all (Knowledge). This aligns with a similar qualitative study conducted by Bussières and colleagues [21] in a population of chiropractors in North America. This also aligns with a previous cross-sectional survey of chiropractors in NL, which found that although half of respondents were aware of radiographic guidelines, one quarter of them did not use guidelines to inform clinical decisions [15]. While chiropractors may have knowledge of the guidelines, their level of understanding of these guidelines was not explored. This may account for chiropractors expressing that their decision for ordering imaging was sometimes due to their “gut feeling” (Memory, attention, and decision processes) or because not ordering imaging may result in a missed diagnosis (Beliefs about consequences). Not having a deeper understanding of the information contained in radiographic guidelines may result in diagnostic uncertainty, which has also been identified as a barrier to reducing general medical practitioner referral for non-indicated imaging in a study by Jenkins and colleagues [25].
Many enablers to guideline adherence and appropriate imaging ordering behaviours for LBP found in our current study were similar to those previously reported in the literature. Compared to other chiropractors in North America, participating chiropractors in NL also believed that it was their role to manage LBP without imaging and that chiropractors should not routinely use imaging in their practices (Social/professional role and identity) [21]. Similarly, compared to known enablers to reducing general medical practitioner referral for non-indicated imaging, participating chiropractors in NL also reported awareness of guidelines (Knowledge), being able to recall guidelines (Memory, attention, and decision processes), and knew the potential negative consequences of non-indicated imaging (Beliefs about consequences) [25]. Additionally, having good communication skills were seen both as an important skill to help with managing LBP without imaging (Skills) and as a potential strategy to use for interventions targeting non-indicated imaging for LBP (Behavioural regulation) [25].
Our study identified eight theoretical domains that appeared to be less relevant as factors influencing chiropractors’ adherence to radiographic guidelines for LBP. Most of the beliefs within these theoretical domains represented enablers or had no influence to these target behaviours and were therefore less likely to inform intervention design. This is different from what was previously reported in the literature on factors affecting guideline adherence and appropriate imaging ordering behaviours in chiropractors and physicians (i.e., they were previously identified as barriers in other populations) [21, 25, 26]. The chiropractors interviewed in our study reported that their imaging ordering behaviours were not influenced by patients, colleagues, or other healthcare providers (Social influences), whereas chiropractors and physicians in previous studies stated they were influenced by their patients wanting to receive an X-ray [21, 26]. The results of our current study align with the results of a survey of chiropractors from NL, where 87% of chiropractors reported that they were not likely to refer for an X-ray just because patients expected it [15]. Similarly, chiropractors in our study felt confident in their ability to manage LBP without imaging, while other studies have demonstrated uncertainty and a lack of confidence (Beliefs about capabilities) [21, 25]. When compared to other studies on physician-reported barriers to radiographic guideline adherence, chiropractors in our study reported that time was not a limiting factor in their ability to manage LBP without imaging (Environmental context and resources) [25, 26]. This may be due to differences in the organisation of a typical clinical encounter between chiropractors and physicians, such as appointment duration and/or number of conditions discussed per appointment. However, it may also be due to other factors such as continued messaging around this issue, years of experience, etc. These interprofessional factors may need to be taken into consideration when designing future interventions to target LBP radiographic guideline adherence.
Strengths and limitations
A strength of our study is that we used the TDF to identify barriers and enablers to the adherence to radiographic guidelines for LBP, which may be used to inform the design of behaviour change interventions targeted at reducing non-indicated imaging for LBP [19]. There are several limitations to our study. Only two focus groups were conducted, resulting in the possibility that data saturation was not reached; however, there were many similar beliefs expressed between the two focus groups. A total of 12 chiropractors were included in the study, which represented approximately 17% of the chiropractors in NL. Since the chiropractors who participated in the study volunteered for the study themselves, it is possible that chiropractors who adhere to radiographic guidelines and have appropriate imaging ordering behaviours were more likely to volunteer for the study. Anecdotally, it has been suggested that chiropractors in the province of NL generally have a strong sense of community and similar practice styles (Diversified technique). The results of our study may be less generalisable to chiropractors in other regions where access to imaging is different or to chiropractors with different practice styles. Another limitation is that the interview guide used in our study was based on the original version of the TDF with 12 domains, allowing comparison with findings from a previous qualitative study conducted among Quebec and Ontario chiropractors, but the data were coded according to the more updated and validated version of the TDF with 14 domains. The updated version of the TDF is similar in structure and content to the original version of the TDF. Two key differences between the two versions of the TDF are that the domains were expanded into Beliefs about capabilities and Optimism (previously only Beliefs about capabilities), and Beliefs about consequences and Reinforcement (previously only Beliefs about consequences). This likely explains why no utterances were coded into the domain of Optimism, and thus may have been considered a less relevant domain.
Future directions
Based on the factors we identified as key to influencing chiropractors’ LBP imaging ordering behaviours and adherence to radiographic guidelines, the domains can be mapped to behaviour change techniques [27] in order to develop an intervention to target these behaviours for chiropractors in NL.