Family physicians in our study had strong intentions to support women in making informed decisions about breast cancer screening. Perceived behavioral control was the variable most strongly associated with their intention, followed by attitude and then social norm. These findings concur with the results of two systematic reviews assessing the efficacy of the TPB in predicting intention and behavior. They also found that health professionals perceived behavioral control as the strongest predictor of intention, followed by attitude, while social norm was the weakest predictor [12, 19]. However, ours is the first study using a theoretical model to assess family physicians’ intention to support women in making informed decisions about screening for cancer.
Although research findings illustrate the numerous benefits of informed and shared decision making (informed decisions by patients that involve both patient and practitioner) in clinical practice [6, 20, 21], health professionals still perceive many barriers to its implementation. In a systematic review on barriers and facilitators to implementing shared decision making in clinical practice [17], authors found that the three most reported barriers in 38 studies were time constraints (22/38), and lack of applicability due to patient characteristics (18/38) and clinical context (16/38). The three most reported facilitators were provider motivation (23/38), positive impact on the clinical process (16/38), and on patient outcomes (16/38). Family physicians in our study also identified time constraints, lack of relevant information and decision support tools as important barriers to supporting women in making informed decisions about breast cancer screening. It is unclear if using patient decision aids during consultation has a significant impact on the length of consultation. In a Cochrane review of nine randomized trials, the length of consultation in decision aids groups compared to usual care groups varied between −8 min and +23 min with a median of + 2.55 min; six trials reported no difference in the length of the consultation [21]. Physicians must however devote time to training to appropriately use shared/informed decision making techniques and tools.
Physicians also reported remuneration, organizational structure, self-efficacy, motivation, awareness, knowledge of the evidence, and the characteristics of the targeted women. According to the TPB, barriers and facilitators identified by physicians in our study are mainly associated with perceived behavioral control and attitude.
We also used a similar questionnaire with the same 12 TPB questions to survey (online) a sample of 840 primary care nurses in contact with women targeted by the QBCSP. Results of the survey demonstrated that perceived behavioral control was also the strongest predictor of nurses’ intention, followed by attitude. The main barriers limiting nurses’ support for women in making informed decision about breast cancer screening were lack of relevant decision support tools and training in informed decision making [22].
In response to the results of both studies, the MHSS in collaboration with l’Institut national de santé publique du Québec (National Public Health Institute of Quebec) and the Canada Research Chair in Implementation of Shared Decision Making in Primary Care at Université Laval created a 2-h theory-based online tutorial to help health professionals support women targeted by the QBCSP to make informed decisions about breast cancer screening with mammography. The tutorial focuses on shared/informed decision making techniques and tools emphasizing efficient use of consultation time. It is available (only in French) since 2013 at http://campusvirtuel.inspq.qc.ca/pages/decision-sein for a nominal fee and is provided free of charge since 2014 to all family physicians and nurses in the Province of Quebec at http://caducee.fmoq.org/ext/fmoq/accueilPublique.cnx.
Strengths and limitations
This study demonstrated a number of strengths. Firstly, as intention has been repeatedly shown to predict behavior [14], we based our questionnaire on the Theory of Planned Behavior, a validated model that has been used in many international research projects to predict intention and its determinants vis-à-vis the adoption of healthcare behaviors [12]. Second, we complemented our assessment by asking physicians to identify barriers and facilitators to adopting the behavior, allowing us to make concrete suggestions for the design of interventions targeting behavior change. Third, according to systematic reviews, our study appears to be one of the largest assessments of health professionals’ intentions that use a socio-cognitive theory [12, 19].
This study also had some limitations. Our convenience sample of family physicians had just attended a presentation on informed/shared decision making and cancer screening, which might explain the high intention observed. Our results may not be generalizable to all family physicians in Canada or other countries and may be limited to physicians who just attended a similar presentation. In addition, the response rate in the selected sample was 38 %. This response rate may indirectly indicate lack of physicians’ interest in the topic and one could speculate that the intention of non-respondents would have been lower than in respondents. Nevertheless the response rate is high enough to indicate that a significant proportion of participants in the two CME events had a high intention to support women in making informed decisions about breast cancer screening. We do not know however if their intention was already strong or if it was a result of attending the presentation. Evaluating the effect of an intervention aimed at modifying the intention and behaviour of physicians would require collecting baseline data in participants and ideally in comparison with a control group.
Factors not identified in our study may constitute other barriers for supporting women in making informed decisions about breast cancer screening, for example, physicians’ misunderstanding of cancer screening statistics. Wegwarth et al. observed that 69 % of surveyed primary care physicians recommended a cancer screening test after being presented with irrelevant evidence—e.g. that finding more cases of cancer in screened as opposed to unscreened populations proves that screening saves lives—compared to 23 % who were presented with relevant evidence [23].
Finally, further research is needed to assess the actual behavior of family physicians in supporting women in making an informed decision about breast cancer screening. This might improve accurate targeting of interventions.