Brief verbal intervention to address inappropriate prescriptions of chinese patent medicines among western practitioners in primary health care (BRAVERY): a study protocol for an unannounced standardized patient experiment with a factorial design randomized controlled trial in China

Abstract

Introduction

Chinese patent medicines, produced using advanced pharmaceutical techniques and available in various forms, including powders, granules, tablets, pills, and capsules, finds extensive utilization among Western medicine practitioners in primary healthcare (WMP-PHC). However, the inappropriate overprescribing of these medicines has led to significant resource waste and raised considerable concerns. Therefore, we aim to address related knowledge gaps by employing unannounced standardized patients (USPs) as a method, for both measurement and intervention research. Specifically, in this paper, we present a study protocol that aims to develop and evaluate the effectiveness of brief verbal interventions (BVI) delivered by USPs, with the objective of improving the appropriate prescription of Chinese patent medicines. The study aims to equip patients with simple and easily implementable interventions to enhance the appropriate prescription of Chinese patent medicines. Furthermore, The findings from this study will provide valuable insights for policymakers, enabling them to comprehend the current levels of inappropriate Chinese patent medicines prescription and develop targeted policy interventions.

Methods and analysis

We will record a total of 576 encounters in primary healthcare (PHC) facilities across two cities in China. The data will be randomized using a 2 × 2 × 2 × 2 factorial design randomized controlled trial (RCT), which includes factors such as financial incentives, knowledge and skills, prescribing habits, and patient expectation. USPs will collect data, including retrieving prescriptions and documenting the process of medical encounters. The primary outcome evaluation focuses on the appropriateness of Chinese patent medicines prescriptions. Secondary outcomes include the quality of the consultation process, patient satisfaction, cost information, service time, and appropriateness of antibiotic prescriptions. Descriptive analysis will be performed for the survey results, and the difference in outcomes between interventions and control providers will be compared and statistically tested using generalized linear mixed model (GLMM).

Trial registration number

The study has been registered at the China Clinical Trials Registry (ChiCTR2300077913) on 23 November 2023.

Strengths and limitations of this study

• To the best of our knowledge, this study is the first to offer evidence of interventions aimed at addressing inappropriate prescription of Chinese patent medicines in primary healthcare institutions in China.

• Brief verbal intervention as a method of communication-based intervention during medical consultations, focus on prescription adjustments from the patient’s perspective, rather than relying on policies that are difficult to change. This approach empowers healthcare consumers in a context of information asymmetry, effectively encouraging doctors to modify their prescribing behaviors. Although this study specifically examines the effect of brief verbal interventions from the patient’s perspective on the prescription of Chinese patent medicines by primary care Western physicians, this approach can be expanded. The prescription of Chinese patent medicines serves as a particular context, but the broader concept of brief verbal intervention can be applied to influence Western practitioners’ medical decision-making and improve the quality of care they provide.

• The utilization of USPs, which is a method where individuals are trained to depict patients in a standardized manner within medical scenarios, is becoming more prevalent in low-income countries for evaluating the quality of medical care. Research focusing on Chinese patent medicines reveals several advantages to employing this approach. Firstly, USPs can exhibit consistent symptoms, medical history, and emotions, while adhering to predefined standards for consultation, diagnosis, and treatment. This ensures a more objective evaluation of Chinese patent medicines appropriateness. Secondly, USPs are well-suited for introducing BVI, because of the researcher’s ability to vary verbal presentation (scripted lines) by the USP, allowing for measuring the effectiveness of the varied intervention while keeping other patient-side confounding factors constant. Lastly, USPs serve as a form of unannounced visits, minimizing the Hawthorne effect and providing researchers with direct and reliable information on appropriate Chinese patent medicines prescriptions.

• The factorial design RCT enables the evaluation of multiple intervention components simultaneously, including the individual effects (main effects) and combined effects (interaction effects) of multiple BVIs. This design ensures robust research evidence and effective control over research costs.

• This study also has limitations. Although we designed different scripted lines for USPs as proxy variables to reflect potential mechanisms such as financial incentives, knowledge and skills, prescribing habits and patient expectation, it should be noted that these scripted lines may not fully capture the mechanisms. Despite our efforts to minimize bias through the inclusion of expert groups and stakeholders in the development of lines, it is important to acknowledge this limitation.

Introduction

In recent years, China has focused on advancing traditional Chinese medicine (TCM), with Chinese patent medicines playing a crucial role. Chinese patent medicines refers to traditional Chinese herbal products manufactured using modern formulation techniques. These formulations come in various forms, including but not limited to powders, granules, tablets, and capsules, distinguishing them from traditional Chinese medicine preparations such as ointments, pills, pellets, and powders, which are typically prepared through methods like decoction or grinding by traditional Chinese medicine practitioners [1, 2]. Under the influence of national policies supporting both TCM and Western medicine, Chinese patent medicines has become widely available in Chinese healthcare system. In the 2023 edition of the National Essential Medicines List, the total number of medications listed in the catalog has reached 3,088, with 1,390 of them being Chinese patent medicines [3]. Chinese patent medicine is also frequently prescribed in clinical practice, constituting approximately 62.13-77.48% of prescriptions in China [4, 5]. The Chinese patent medicines market has grown significantly, reaching 500 billion RMB in 2023 [6]. As previously mentioned, the inclusion of Chinese patent medicines in the Essential Medicine List, the prescription rates of Chinese patent medicines in clinical practice, and the market value of Chinese patent medicines collectively attest to its widespread utilization in the healthcare sector of China.

The issue of appropriate prescriptions of Chinese patent medicines by WMP-PHC is prominent. According to the World Health Organization’s definition, appropriate prescriptions involves patients receiving suitable doses of medications to meet their individual needs, within an appropriate timeframe, and at the lowest cost for their clinical requirements [7]. The issue of appropriate prescriptions of Chinese patent medicines may be observed through under-prescribing, over-prescribing, incorrect prescribing, extravagant prescribing, and multiple prescribing [7, 8]. The unique characteristics of Chinese patent medicines make it easy for WMP-PHC to engage in inappropriate prescriptions. Traditional Chinese medicine emphasizes syndrome differentiation for treatment, where “differentiation” involves analyzing and synthesizing data, symptoms, and signs collected through observation, listening and smelling, questioning, and pulse feeling. This process helps in determining the cause, nature, location, and relationships between pathogenic and healthy factors, leading to the identification of a specific syndrome, which is crucial for treatment [9]. Without systematic training in syndrome differentiation, WMP-PHC may make errors when prescribing Chinese patent medicines. Research indicates that 86.2% of WMP-PHC prescribe Chinese patent medicines without differentiating traditional Chinese medical syndromes, relying solely on Western medical diagnoses [10, 11]. Therefore, there is a significant safety risk associated with WMP-PHC prescribing Chinese patent medicines. The inappropriate prescriptions can compromise patient health, waste healthcare resources, and reduce patient confidence and satisfaction in the healthcare system.

Even though there is ample evidence indicating the low quality of Chinese patent medicines prescriptions issued by WMP-PHC, the existing information lacks comprehensive details concerning content and methods. Firstly, PHC medical records, particularly outpatient records, are often incomplete and may not fully reflect the diagnosis, treatment, and prescription processes. Secondly, medical records can adequately reflect the quality of documentation, but it only serves as a proxy variable for healthcare quality. For instance, if the disease diagnosis is incorrect, prescribing the right medication would still be considered incorrect. However, during prescription review, it may not always be possible to ascertain the accuracy of the disease diagnosis. Thirdly, medical records can partially reflect whether doctors have performed specific diagnostic and treatment procedures but may not accurately reflect their accuracy. For example, while medical records may indicate whether certain examinations have been conducted, they may not reflect whether these examinations were performed in accordance with established standards. To address these limitations, further research is needed to gather data on the inappropriate prescription of Chinese patent medicines by WMP-PHC, using robust measurement tools that capture the nuances of clinical practice in PHC institutions.

Unannounced standardized patients (USPs), which are individuals trained to portray a pre-scripted scenario and later present it to a provider in a typical visit, offer a novel and reliable research method for investigating and assessing interventions [7, 12, 13] to improve the inappropriate prescription of Chinese patent medicines, including: (a) offering an objective and direct evaluation of care during a real visit; (b) being unannounced, thereby eliminating the Hawthorne effect, where individuals alter their behavior in response to awareness of being observed; (c) maintaining standardization in case presentation, providing a natural control for case mix; and (d) ensuring immediate recording of assessment results, minimizing recall bias. Additionally, the use of USPs can allow for identifying the effects of different types of patient presentation through randomly assigning them to sampled providers. The USP method is recognized as a gold standard for evaluating clinical practices due to its objectivity, unannounced nature (eliminating Hawthorne effect), standardized case presentations, and immediate recording of assessment results. Our team has gained extensive experience using USP to assess PHC quality over the past five years through the ACACIA (Primary heAlth Care quAlity Cohort In chinA) study: https://www.researchgate.net/project/ACACIA-Study) project [14,15,16]. We have developed and validated 11 USP cases covering common PHC diseases. ACACIA collaborates with the National Health Commission Statistical Information Center to ensure provider representativeness and conducting 2,200 USP-clinician encounters nationwide in China. In this research, our evaluation focuses on Chinese patent medicines prescription appropriateness, considering diagnosis, symptoms, medical history, and treatment goals, guided by TCM principles and evidence-based medicine. We have been developing evaluation indicators and methods, combining the principles of TCM with evidence-based medicine, for assessing the appropriate prescription of CPM, and we have just completed the clinical guidelines on treating influenza in adult patients with Chinese patent medicines [17]. In this study, we will also refer to it as USP cases. Currently, while the USP method has primarily been used to study antibiotic prescriptions [18], it can be expanded to include the research field of Chinese patent medicines. By leveraging the strengths of the USP method, we can gather valuable insights into the inappropriate prescription of Chinese patent medicines and develop effective interventions to improve more appropriate use. In short, we could use USPs to create experimental conditions while keeping other USP factors constant, enabling us to conduct multi-group randomized controlled trials. This comprehensive approach aims to shed light on Chinese patent medicines inappropriate prescription and develop effective strategies to address it. In addition, we will collect data on the appropriateness of antibiotic prescriptions. This will allow us to contrast the appropriateness prescriptions for Chinese patent medicines with those for antibiotics, providing insights into prescription practices for both types of medication in China.

In the challenging context of healthcare system transformation, it is valuable to investigate how patients themselves contribute to shaping healthcare quality within the dynamics of doctor-patient interactions. Brief verbal intervention (BVI) is a commonly used, simple, and effective method in PHC institutions, such as smoking cessation interventions and reducing alcohol intake [19]. It refers to an approach where patients offer concise suggestions or consultations to doctors. In this study, we will use the USP approach to test BVIs in improving inappropriate prescriptions of Chinese patent medicines. The design of the BVI is primarily tailored to address the issue of over-prescribing. Firstly, we will conduct training for USP to ensure their accurate communication of BVI. Secondly, we can modify specific components (e.g., different scripted lines presented by USPs corresponding to BVI interventions) across healthcare providers while maintaining consistency in other USP case presentation. Consequently, any variations in intervention measures can be entirely attributed to this specific component. Therefore, any changes in the intervention can be attributed solely to that specific component. The choice of a factorial design randomized controlled trial (RCT), primarily considers its efficiency, allowing multiple interventions to be tested with a smaller sample size and the ability to examine interactions between interventions [20]. This design is suitable for detecting the effects of multiple interventions on various mechanisms in our study. Specifically, negative BVIs in the factorial design RCT will be addressed as cross-sectional survey results.

The key aims of this study are as follows: 1.To conduct an in-depth analysis of the factors influencing the appropriate prescription of Chinese patent medicines. 2. To depict the types, quantities, and costs of Chinese patent medicines prescription. 3. To evaluate the effectiveness of BVI in improving the quality of Chinese patent medicines prescriptions.

Trial design and methods

Development of USP cases

We plan to develop 2 USP cases, and in the elaboration of this protocol, we will use influenza cases as examples to illustrate the methodological details in each section. The case development team and case review expert team, comprising an evidence-based researcher, clinical specialists, PHC practitioners, and a coordinator, will collaborate in the development of USP cases. Their focus will be on reviewing the case prototypes, clinical scenarios, disguise plan, USP-clinician encounter, and quality checklist sheets. The details of our checklist development protocol were described in another paper [14]. These aspects will be based on clinical evidence-based guidelines [17], including history, physical examinations, laboratory and imaging studies, diagnosis, and management plans. Differential diagnosis and treatment in Chinese patent medicines prescriptions, as seen in traditional Chinese medicine internal medicine, will also be considered. For example, influenza can be categorized as wind-colds, wind-heats, colds with a deficiency in qi, colds with a deficiency in yin, summer-heat colds, and damp colds (Table 1 serves as an illustrative example to demonstrate the difference between wind-colds and wind-heats [17, 21]).

Table 1 Wind-heat and wind-cold syndrome of influenza

Brief verbal interventions

In September 2022, our research team conducted an independent study using a multi-stage stratified sampling method with 214 doctors from primary healthcare institutions in Gansu Province as research subjects. Through a questionnaire survey and employing the mixed logit model in a discrete choice experiment, the results revealed that economic incentives, patient willingness, disease severity, drug effectiveness, and drug adverse reactions all significantly influence the prescription behavior of WMP-PHC [5]. Based on these five intervention strategies and project resources, we have determined that the final intervention strategies for this proposed study are to include financial incentives, knowledge and skills, prescribing habits and patient expectation.

The design of the BVI is primarily tailored to address the issue of over-prescribing. We will develop BVIs using an expert panel approach. The focus group will include 1 WMP-PHC, 1 expert in anthropology and sociology, 1 USP with ACACIA experience, and 2 actual patients with demographics and economic profiles similar to our USP cases. Attendees will discuss and revise the BVIs based on scripted lines design requirements, which include: (1) the ability to curtail or enhance the appropriate prescriptions of Chinese patent medicines, (2) brevity for easy memorization and execution by USP, (3) clear and explicit meaning, and (4) a tone and content consistent with the identity of USP in the case design. For the purpose outlined in this protocol, we have initially crafted BVIs for influenza cases for USPs, as indicated in Fig. 1, drawing from our current experience.

Fig. 1

Example of BVIs in influenza case for USP. Note: The specific interventions will be refined during the project implementation. The provided examples serve as illustrations only

BVIs are brief interventions that will be started and concluded with a single USP visit, so we expect few or no cases of discontinuing an allocated intervention. In the case a provider refuses to provide health service, the USP will record the reason and visit a replacement provider with similar characteristics.

Study design and setting

The study is designed as a prospective, single-blinded, multi-center factorial trial with 4 factors. This protocol follows the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) checklist [22], and the study flowchart is presented in Fig. 2. The study will be conducted in primary healthcare institutions in Guangzhou, Shenzhan and Zhanjiang. Guangzhou is renowned for its traditional Chinese medicine and advanced economy. Shenzhen, a city with a large immigrant population, has experienced rapid economic development, attracting people from various regions across the country. In contrast, Zhanjiang has a relatively modest economic development, with a population primarily consisting of indigenous residents. These three cities collectively provide a diverse representation of the research settings.

Fig. 2

The study flow chart

Factorial design RCT is an efficient choice for identifying what component to include in a multicomponent intervention [23]. By combining data across multiple factors, factorial design RCT increases statistical power to test the marginal treatment effects compared to separate trials on individual components [24]. The joint modeling of multiple main effects and interactions also enhances the partition of variance and further increases estimation efficiency and statistical power [25]. Notably, factorial design RCT allows for the examination of interaction effects among different interventions. When 4 BVIs are tested, the saturated analytical model can include 6 two-way interactions, 4 three-way interactions, and 1 four-way interactions (Fig. 3). It should be noted that among the 16 combinations of intervention components in the factorial design RCT, the focus of the test is the 4 marginal effects of BVIs. Multiple testing adjustments are debatable (e.g., Freidlin, B., & Korn, E. L. (2017). Two-by-two factorial cancer treatment trials: is sufficient attention being paid to possible interactions?. JNCI: Journal of the National Cancer Institute, 109(9), djx146.) and not considered in this studied.

Fig. 3

Combination of intervention in factorial design RCT. Note: the symbol ‘-’ represents ‘no’ or absence of an intervention mechanism, while the symbol ‘+’ represents ‘yes’ or presence of an intervention mechanism

Participants and recruitment

For the purpose of this study, we will adopt the following inclusion and exclusion of PHC institutions and practitioners:

• (1). PHC institutions: this includes outpatient services provided by the internal medicine departments at secondary PHC institutions, primary PHC institutions, and institutions of undefined level. Institutions with unstable operations, as well as specialty care hospitals and clinics, will be excluded from the study.

• (2). WMP-PHC: WMP-PHC can be classified into three main types: licensed physicians, licensed assistant physicians, and certified village doctors. Their scope of practice is confined to general medicine, internal medicine, obstetrics, and pediatrics.

Sampling frame, sampling and sample size

We will develop the sampling frame of all PHC institutions in Guangzhou, Shenzhen and Zhanjiang that meet our inclusion and exclusion criteria by collaborating with local health authorities. We will employ a random digit table method to sample institutions, ensuring an unbiased and representative sample for the study. Each PHC institution will be visited once by USPs.

For the factorial design RCT, based on the current ACACIA project, the expected appropriate prescription rate of Chinese patent medicines is 50% in the control [26]. A 25% decrease can be considered clinically significant based on discussions with health economists, implementation science experts, and clinical physicians at the early stages of this project. In a two-proportion test for factorial design RCT on the main effect of each component, a sample size across all 16 combinational conditions of 384 (24 physicians each) can attain 80% power with a two-sided type- I error rate of 0.05. This study conducted a randomized controlled trial in three cities, taking into account the relatively consistent healthcare quality across provinces and regions, with an ICC set at 0.001. As a result, the calculated design effect (Deff) is 1.127, leading to a required sample size of 433. Additionally, considering the three cities (Guangzhou, Shenzhen, and Zhanjiang), PHC institutions Level (three levels of PHC institutions-secondary PHC institutions, primary PHC institutions, and undefined-level PHC institutions), profit model (two types of hospital profit models-public and private) as well as 2 case types and 16 interventions, a total of 576 visits (18*2*16 = 576) is needed. Therefore, the final sample size is determined to be 576 visits, with 36 visits per intervention group.

Randomization and group allocation

First, within the overall sampling frame of the cities of Guangzhou, Shenzhen, and Zhanjiang, the random seed was set using R software. Stratification was performed based on three hospital levels, two profit models, and two case types. Second, within each stratum, random numbers were generated using Excel to assign hospitals to one of the 16 experimental conditions of the factorial trial through complete random assignment. Subsequently, these clinics will be allocated to different experimental conditions according to the order of the assigned random numbers. Each serial number will be assigned one USP visit. This entire process will be carried out by a statistician unaffiliated with the project, using R software. The goal is to address sample imbalance and enhance the comparability of samples across different intervention groups.

Blinding

In this study, the WMP-PHC will not be informed about the visits by USPs, ensuring a single-blind design. However, USPs will be aware of the intervention and data collection procedures, so the study cannot be fully double-blinded. Nevertheless, data analysts will be blinded to reduce subjective analysis. Data will be de-identified, and the BVI grouping information will be concealed during analysis to maintain anonymity.

Since informed consent will not be obtained, the likelihood of unblinding occurring at the level of PHC institutions is minimal, if not impossible. However, in the event that unblinding does occur, a replacement provider with similar characteristics will be identified to conduct the visit.

Data collection

USP disguise plan

USPs will mention having had a fever the previous day and taking antipyretics. Symptoms like a yellow nose and sore throat will further enhance the portrayal of wind-heat syndrome. The effectiveness of this disguise plan has been tested in the ACACIA project with a 0% detection rate. All USPs will undergo intensive training to present a letter containing their university’s contact information, explaining their role in the research. This is to address any potential confrontations and to ensure they avoid any potentially harmful examinations.

USP validation

This study will employ Delphi expert method to validate the USP measurement, following the COSMIN theoretical framework [27]. The validation methods are described in detail in our ACACIA research protocol [14] and Supplement Table 1.

USP recruitment

We will mobilize the universities involved in the ACACIA project research network to recruit local survey participants through social media, offline posters, and promotion by researchers. We will recruit and train USPs to implement interventions in different groups. All USPs must meet the following criteria to be eligible for the study: (1) people with a suitable age and physique to portray the case; (2) fluent native speakers of the local language in the area; and (3) having a good memory.

Patient and public involvement

When developing USP cases and designing BVI scripts, we will invite patients with a history of the relevant disease to participate in the development process. However, when conducting formal USP visits, patients will not be involved.

Outcomes

The primary outcome of this study will be the appropriateness of Chinese patent medicines prescription, a dichotomous variable. This outcome will be evaluated by a team of traditional Chinese medicine experts, who will assess the appropriateness of Chinese patent medicines prescriptions for the selected cases based on the principles of traditional Chinese medicine and evidence from evidence-based medicine, and we have just completed the clinical guidelines on treating influenza in adult patients with Chinese patent medicines [17].

Specifically, the appropriateness of Chinese patent medicines prescriptions will be assessed based on two dimensions: indication and dosage.

• For dimension 1 (indication), the traditional Chinese medicine experts will classify each prescribed medication according to guidelines as either “recommended prescription,” “completely useless but harmless treatment,” or “harmful prescription.” The prescription will be considered appropriate if it meets the following criteria:

D1 (appropriate prescription) = (#1 AND #2 AND #3) OR #4.

# 1. It includes the indication “recommended prescription”.

# 2. It does not include the indication “completely useless but harmless prescription”.

# 3. It does not include the indication “harmful prescription”.

# 4. no traditional Chinese medicine is prescribed under this dimension.

Prescriptions that do not meet these criteria will be classified as not meeting the indication (1-D1).

• For dimension 2 (dosage), the dosage will be considered appropriate (D2) if it complies with the instructions provided in the medication’s package insert. Prescriptions that do not meet this criterion will be classified as inappropriate (1-D2).

Chinese patent medicines prescriptions will be considered appropriate only if it meets both criteria: it meets the indication and the dosage is appropriate (D1∩D2).

Antibiotics prescribed for viral respiratory tract infections will be considered inappropriate. Therefore, if no antibiotic prescription is provided, it is considered appropriate, while any other situation is deemed inappropriate.

We will collect a variety of quality information and other related explanatory variables. In this study, we adopted Institute of Medicine (IOM) framework [28, 29], which defines six dimensions of healthcare quality: effectiveness (avoiding underuse and misuse), safety (avoiding harm), patient-centeredness (respecting and responding to individual preferences), timeliness, efficiency (avoiding waste), and equity (ensuring healthcare quality does not vary based on individual characteristics). In this intervention study, considering the content of BVI, we posit that improvements cannot be made in the dimensions of timeliness and equity.

Effectiveness (avoiding underuse and misuse) and safety (avoiding harm), traditional technical goals of quality of care, will be evaluated through the quality checklist sheets discussed above. In short, we will also evaluate WMP-PHC adherence to best practices as the secondary outcome, such as the percentage of adherence to guideline-recommended procedures performed. The patient experience will be assessed with patient-centeredness (PPPC-R) rating scale by USPs [30, 31]. Employing a 4-point Likert scale, the PPPC Rating Scale appraises patient-centeredness across three dimensions: exploration of disease and illness experiences, understanding the whole person, and establishing common ground. A detailed outcome evaluation will include the appropriateness of Chinese patent medicines prescription, quality of consultation process, patient satisfaction, cost information and service time. Table 2 summarizes all outcomes to be collected.

Table 2 Variables and their definitions

Almost all data will be collected through visits conducted by USPs. USPs will visit accompanied by a peer as a ‘friend’. When a USP is being examined by a WMP-PHC, the companion will observe the facility environment and treatment procedures. At the end of each encounter, the USPs will request treatment prescriptions. Each USP and the companion will jointly complete quality checklists and other data forms on a smartphone within 15 min after leaving the sampled PHC institution.

Data analysis

The data will be analyzed based on the intention-to-treat (ITT) principle to compare the primary and secondary outcomes of the initially assigned groups. For continuous variables (based on the distribution), the baseline characteristics of each group will be described using the mean (standard deviation, SD) or median (interquartile range, IQR). For categorical variables, the frequencies (percentages) will be used to describe them. The analysis will involve the use of a logistic regression model for factorial design RCT. Continuous outcomes will be analyzed using generalized linear mixed model (GLMM). Additionally, we will employ logistic regression to investigate the factors associated with appropriate prescriptions in Chinese patent medicines, including categories, quantities, costs, and appropriateness. Subgroup analyses will be performed, focusing on factors limited to type of disease, geographic region, type of healthcare institution, and type of physician. The comparison of the appropriateness of antibiotic prescriptions and Chinese patent medicines prescriptions will be conducted using the chi-square test. Missing data will be imputed using multiple imputation in the GLMM.

We anticipate a low dropout rate as the intervention is provided by USPs, and WMP-PHC will passively receive the intervention. Additionally, the intervention will take place within a short timeframe of a single encounter, hence there will be no follow-up encounters. After the encounter is concluded, all data will be immediately entered into the REDCap. REDCap incorporates bank-level security features, granting access to the data exclusively to the investigators involved in this study. All study forms, including signed consent forms, will be securely and conveniently stored within the REDCap system. All data analyses will be performed with R version 4.3.0 and two-sided P value < 0.05 will be deemed significant.

Trial organization and monitoring

USPs will be assigned specific roles and must accurately portray them, maintain fidelity, and complete the reporting forms competently. A project manager will monitor all sites and hold weekly conferences to address performance issues. Field information will be collected using REDCap app on mobile phones, which ensures data security and de-identifies facility and physician identifiers during analysis [32].

Discussion

This factorial randomized controlled trial aims to investigate the impact of BVIs delivered by USPs on reducing the inappropriate prescription of Chinese patent medicines in PHC institutions in China. The design of the BVI is primarily tailored to address the issue of over-prescribing [7]. To the best of our knowledge, this study represents the first attempt to explore the intervention strategies and mechanisms for addressing this issue. The results of this study will not only provide essential empirical evidence for policymakers, healthcare providers, and patients to ensure the provision of high-quality Chinese patent medicines prescriptions, as BVIs can be self-implemented by patients. Additionally, the study holds significance in identifying the most effective intervention and potentially uncovering robust underlying mechanisms contributing to its efficacy. The utilization of USPs in this study provides a reliable approach for measuring and intervening the quality of services.

This study has several strengths. Firstly, it adopts a progressive approach, examining the current situation of inappropriate prescription of Chinese patent medicines, understanding the underlying mechanisms, and implementing BVIs to improve appropriate prescription. This comprehensive approach will provide valuable evidence and information for the prescription of Chinese patent medicines in PHC institutions. Secondly, BVI can offer a practical and feasible solution to improve the appropriate prescription of Chinese patent medicines, and its effectiveness can shed light on the underlying mechanisms. It also empowers patients to advocate for their health rights. Additionally, the study utilizes the USP approach, which is a valuable tool for prescription evaluation and intervention. USPs provide consistent symptoms and standardized consultation, diagnosis, and treatment, enabling objective evaluation of Chinese patent medicines appropriateness. The unannounced visit nature of USPs reduces Hawthorne effect and enhances the reliability of data. The factorial design RCT employed in this study allows for the examination of multiple interventions and their interaction effects, optimizing research evidence while controlling costs.

However, there are some limitations to the USP methodology. Firstly, the limited number of USP cases may restrict the range of prescriptions providers can make, potentially affecting prescription volume and expenditure. Secondly, although we designed different lines scripted for USPs to present as proxy variables to reflect potential mechanisms, it should be noted that these lines may not fully capture the mechanisms. Despite our efforts to minimize bias through the inclusion of expert groups and stakeholders in the development of line, it is important to acknowledge this limitation.

Through the use of the USP method, this study aims to shed light on the underlying factors that lead to the inappropriate prescription of Chinese patent medicines. By collecting and analyzing actual clinical interactions, the findings will contribute to our understanding of effective strategies for promoting appropriate Chinese patent medicines prescription in PHC institutions. By assessing the impact of this intervention on WMP-PHC prescription practices, the study aims to determine whether patient-focused interventions can play a role in improving the appropriate prescription of Zhongchengyao. We can provide consumers with clear instructions to safeguard their interests and promote healthcare value. Furthermore, the study seeks to identify and validate potential mechanisms, such as financial incentives, prescribing habits, knowledge and skills, and patient expectations, that may influence the inappropriate prescription of Chinese patent medicines. This empirical validation will provide valuable insights into the reasons behind such inappropriate practices.

Ethical considerations and dissemination

This study has received ethical approval from the Institutional Review Board (IRB) of Southern Medical University, China, with a waiver of informed consent from participating general practitioners (Approval #Southern Medical Audit (2023) No. 060). The protocol includes comprehensive descriptions of ethical considerations such as confidentiality, informed consent materials, as well as data management, access, and security protocols. Furthermore, the study has been registered at the China Clinical Trials Registry (ChiCTR2300077913).

Upon completion of the study, the findings will be disseminated to National Health Commission of the People’s Republic of China. The results will also be presented at national and international conferences and published in international peer-reviewed journals. This widespread dissemination of the study’s outcomes will contribute to knowledge sharing and facilitate informed decision-making in healthcare practice.