With its incidence on the rise over the past few decades, liver cancer is one of the most serious malignant tumors globally, as well as the current second leading cause of cancer-related deaths [1]. Worse of all, once the clinical manifestations appear, most patients have entered the advanced stage, where has a low 5-year survival rate, poor quality of life, and unaffordable burden of disease [2,3]. The situation is particularly acute in China, which accounts for more than half of the world’s new liver cancer cases and deaths each year [4]. Although a growing body of research aims at better understanding and increasing the use of cancer screening [5,6] and the fact that a fairly large number of cases can avoid advanced cancer through screening is well-established [7], it remains challenging for researchers and policymakers to persuade or motivate the public (including patients and physicians) to adopt cancer screening. Under the currently severe context of liver cancer prevention and control, there is a critical and urgent need to promote the use of liver cancer screening.
Researchers have been trying to use various theories and models to explain the rational mechanism of human behavior, such as the Theory of planned behavior (TPB) developed by Ajzen [8], which is one of the most influential and widespread theories to predict behavioral intention [9]. It presumes that people’s particular behavior can be predicted and explained via their intention. In turn, the intention is functioned by three elements, namely attitude, subjective norms, and perceived behavior control [8]. Attitude reflects the perception or evaluation of performing a particular behavior. Perceived behavior control is defined as the perception of the controllable extent of performing a specific behavior. Subjective norms are perceived social pressures that whether people important to individuals think the behavior should be performed. To date, the TPB has been applied in research about health professionals’ intentions [10], including the acceptance of innovative health technology [11,12] and the adherence to clinical guidelines [13]. And numerous studies basing on TPB have explained the over fifty percent of the total variance of intention [14–16].
According to Ajzen, the additional predictors are allowed in the TPB to improve the explanatory power in intentions [8], and given the calls for more consideration of the social environment aspect of health issues [17,18]. To some extent, subjective norms in the TPB are virtually a kind of social norm [19,20]. Social norms shape people’s motivation and behavior based on the social environment [21]. It can be understood as the perceived prevalence of a behavior of others and the perceptions of how others think about or evaluate a behavior [22], which may come from multiple resources, such as the people, organizations, or industries around us. The perceptions from those around us are personal norms, namely subjective norms, which have been addressed in the TPB. While the influence of the perceptions from the organization and the industry on the individual can be called the organizational norms and the industrial norms, respectively represent the behavioral readiness of the whole members of the hospital and the competition pressure from the peers in the industry. In general, it’s hard to make decisions that aren’t influenced by the persons and various environmental elements around us, and people adjust their behavior and conform to the social expectation by information learned from observing others [23].
To the best of our knowledge, the research object and content were relatively single and fixed in previous studies about cancer screening intention. On the one hand, previous studies mainly look at the patient level, as a number of studies have been conducted to investigate the intentions to use screening of different cancer groups, such as cervical cancer [24], breast cancer [25], prostate cancer [26] and colorectal cancer [27], etc., but rarely focus on the health services provider, i.e., physicians. On the other hand, in a few studies of cancer screening intention for physicians, they focused more on the internal factors at the personal level (for example, the physicians’ attitudes, beliefs, knowledge [28,29], and nonprofessional experiences [30]) than the effect of the surrounding environment of organizational and industrial on the individual. It’s noteworthy that although recently the social norms have received particular attention as the determinants of the adoption of certain behaviors, including cancer screening [6,31], most studies set forth only a single level of social norms, either personal normative beliefs [32] and mimetic pressures [33] at the personal norms level, institutional pressures [34] and organizational culture [35] at the organizational norms level, or industry competition [36] at the industrial norms level. The comprehensive consideration of these three aspects is necessary, especially for the physicians in public hospitals [37], given physicians’ strong dependence on their hospitals and the industrial environment may lead to the internalization of organization norms and industrial norms that contribute greatly to their decision-making [38].
Therefore, since few previous research on cancer screening intention targeting physicians, and lack of the discussion of perceived norms other than the individual, this study aims to determine the predictors of the intention to use liver cancer screening from the physicians’ perspective, and the influence of the potential social norms from the personal, organizational and industrial level. To make the study more pertinent and focused, contrast-enhanced ultrasound (CEUS), one of the confirmed effective screening technology for liver cancer, will be taken as an example to conduct the survey. This study is promising for bridging the gap in the literature about the factors affecting physicians’ intention to use liver cancer screening from the perspective of health services providers. The findings will not only provide direct guidance for giving full play to the role of social norms in promoting the use of CEUS and other liver cancer screening, but also have several implications for expanding the use of other health services/products.