Physicians’ loyalty to branded medicines in low-middle-income countries: A structural equation modeling

Abstract

Objective

As gatekeepers in health continuum, physicians play a pivotal role in persuading patients to consume a specific medicine, and their prescription behavior has a great effect on both healthcare costs and pharmaceutical markets. Taking the important role of physicians in healthcare system into account, in this study we have tried to empirically prioritize those factors that affect physicians’ loyalty behavior in prescribing branded medicines.

Methods

This research is grounded on a survey through which 437 specialist physicians were randomly invited to fill out the questionnaire of the survey. Structural Equation Modeling was performed to evaluate the research model and to test the research hypotheses. In addition to demographic section, six measures were used to evaluate the prescription behavior of physicians in terms of loyalty.

Key findings

The results revealed that there are some factors influencing physicians’ loyalty to branded medicines, among which professional influence is perceived to be the most important factor as compared with others. In contrast, the results rejected this hypothesis that promotional tools such as tangible rewards have a significant effect on physicians’ loyalty behavior.

Conclusions

The results contribute to the pharmaceutical companies endeavoring to develop fair, ethical, and effective marketing strategies to increase physicians’ loyalty to their products. Furthermore, by comparing the results of similar studies, this research has shed light on this fact that influencing factors on brand loyalty may be different across countries over the world.

Keywords

Physicians prescription behavior loyalty pharmaceuticals industry

Introduction

As there is significant information asymmetry between patients and physicians, patients are usually following and trusting the medicine prescribed by physicians.¹ Consequently, physicians’ prescription behavior, as an important gatekeeper toward a branded product, plays a pivotal role in selecting and prescribing the medicines which are needed to treat patients. To select and prescribe these medicines, based on previous successful experiences with special brands, physicians show loyalty to branded medicines in practice.² Such loyalty is commonly encouraged by pharmaceutical companies in many markets to increase their sale.³

Several large-scale surveys have thus far been conducted, which have shown that there are a plenty of factor influencing physicians’ decisions in selecting and prescribing a medicine, including pharmaceutical sales representatives (PSRs), advertising activities, free samples, reasonable prices, quality, key opinion leaders, and behavioral characteristics.^3–6 The top 20 pharmaceutical companies that have the most shares on total promotion, spent a total of $14,784 billion in 2013 on physicians’ advertising, using such approaches as professional meetings (detailing), journal advertising, and direct-to-consumer advertising.⁷

Physicians’ prescription behaviors are mostly dependent upon the physicians’ attitudes as well as norms, experiences with prescription, normative factors, and personal experiences. The influence of patient demand on the drug selection is very low, and accordingly it can be discarded.⁸ Within a study, authors have tried to estimate the effect of price, types of insurance, detailing, and free samples on prescription behavior. They emphasize that both detailing and providing free samples have positive and significant impact on the probable prescription of a medicine.⁹ Through a qualitative study, authors made great endeavors to show that physicians’ preferred behavior is complex, sensitive, and less rational. They highlighted that detailing is one of the most strong pharmaceutical marketing tools and that it is strongly acknowledged as a valuable and swift source of information.² Some authors have made a great deal of effort to illuminate the effect of sampling and detailing on the prescribing behavior of physicians using pooled data and they found that there is a positive and significant relationship between free drug samples and detailing with the number of new prescriptions issued by a physician; they also found that the extent of these effects ranges from moderate to very small.¹⁰

In another study, the authors demonstrated that prescription loyalty mainly happens on the basis of the prior experience of physicians regarding a medicine. They also illustrated that physicians who show persistent behavior are strongly influenced by promotional tools such as detailing activities as compared to their non-persistent behaviors.⁵ Through conducting other research, researchers have also tried to identify the major factors influencing loyalty behavior while prescribing medication. Through a survey with 71 physicians, they found that tangible reward to physicians by the pharmaceutical companies and professional values of PSRs are two key factors affecting prescription loyalty.³ Despite the fact that physicians’ brand loyalty has some advantages for companies, it would be an important concern to health policymakers who are responsible for the quality of patient care and cost.¹ From the healthcare system perspective, physicians who are under the influence of pharmaceutical promotional activities may be persuaded to prescribe medicines, which are not the best option for patients.¹¹ This is the reason some people who advocate patients’ rights contest such promotional tools and find them unethical, and this has resulted in the consideration of some measures to control company advertising activities and physicians’ prescription behavior.¹²

Given the aforementioned facts, the main purpose of this study is to develop a structured model for prioritizing factors affecting physicians’ loyalty to branded medicines. This loyalty contributes to the pharmaceutical companies trying to improve their promotional mix and marketing strategies to increase physicians’ loyalty to their products. In addition, it would be helpful for regulatory bodies desiring to diminish the unethical effect of the marketing activities on prescribing medicines and to improve public health. The rest of this paper is organized accordingly: the related literature on brand loyalty and hypothesis development are discussed in the Literature review and hypothesis development section. The Methods and Results sections present methods and results, respectively. Discussion is presented in the Discussion section, followed by the limitation of the study and conclusion in the subsequent sections, respectively.

Literature review and hypothesis development

The majority of the previous studies focused mostly on fleeting one-off physician’s prescription behavior, and some authors have investigated long-term persistent practices and loyalty to drug prescription.^3,5 As stated earlier, there are influencing factors on physicians’ selection, such as PSR professional value,³ professional influence,¹³ corporate reputation,¹⁴ drug quality,^3,8 and promotional tools^9,10 which have been identified in the literature. Besides the factors mentioned, accessibility of a brand, as a critical factor in low- and middle-income countries, has also been incorporated in this study, according to the model proposed in Figure. 1. Given this model, a brief explanation of all measures and their proposed hypotheses will be outlined.

Figure 1.

Research conceptual model.

PSR professional value

Professional value that reflects ethics, practices, standards, and norms within a commercial environment can guide professional behavior and is commonly shared by peers in a particular profession.¹⁵ Professional value is formed based on PSR similarity and PSR likability in general. With respect to PSR similarity, it shares common interests as well as values, facilitates goals, and also increases the trustworthiness of the PSR.^3,16,17 As for PSR likability, it refers to the physician’s impression that a particular PSR is friendly and nice to meet.

Physicians’ perceptions were influenced by information and the educational support they received from PSRs mainly because this information is obtained with minimal effort and PSRs are valuable sources of information for a busy physician.^5,18 However, at least 35% of physicians deny visiting pharmaceutical representatives at all.⁴ In addition, despite the pharmaceutical industry’s great investment in detailing, the desirable yield may not be achieved.¹⁹ As sometimes physicians perceive that PSRs are neither qualified nor certainly trustworthy, they are not interested in meeting PSRs to receive information over a medicine.²⁰ Consequently, when a PSR represents a high professional value, continuous prescription of the represented drugs is enhanced.¹⁶ Hence, the first hypothesis is as follows:

H1. Prescription loyalty is positively related to PSRs professional values.

Drug quality

Previous studies indicated that if the products of a company are perceived to be high in quality, consumers are more likely to trust them and prefer to repurchase the products.²¹ Similarly, in the pharmaceutical market, evidence shows that the product quality features, including side-effect profiles, efficacy, and dosage forms, influence the sales of a pharmaceutical manufacturer. In addition, physicians’ views on a particular medicine are formed based on their expectations about treatment outcomes and their personal experiences, as mentioned earlier, which affect their prescription behavior.⁸ In other words, physicians rely greatly on the feedback they receive regularly through their patients.⁹ In conclusion, the second hypothesis is described as follows:

H2. Prescription loyalty is positively related to perceived quality of drugs.

Corporate reputation

Corporate reputation, which has been defined as stakeholders’ apperception about a company, is formed from direct experiences or other forms of communication with a company.²² In the pharmaceutical market, corporate reputation is defined as the extent to which the company is admired, trusted, and respected by external stakeholders, particularly physicians. Based on Wright and Lundstrom’s view, if physicians presume that a company’s reputation is well deserved, they are interested in prescribing its products regularly.¹⁴ With this in mind, it is so crucial for leading pharmaceutical companies such as Pfizer, Sanofi, Novartis, etc. to invest hugely in this issue through marketing communications such that they will be assured that their corporate reputation is well formed. Adeosun and Ganiyu²³ have also stated that although corporate reputation may not be considered as an asset on the balance sheet, it affects investors’ confidence, staff recruitment, supplier attitudes and a myriad of other stakeholders, such as physicians. Therefore, the third hypothesis is as follows:

H3. Prescription loyalty is positively related to the level of corporate reputation.

Promotional tools

Promotional tools, including free samples as well as gifts, honoraria, financing for domestic as well as international conference participation, medical education, detailing as well as advertisements on websites and public journals, help physicians to remember the company brands in order to regularly prescribe them.^24–26 Although physicians recall medicines’ names using their memory, free samples given by company representatives may act as long-lasting reminders for them. Therefore, our fourth hypothesis is as follows:

H4. Prescription loyalty is positively related to promotional tools (tangible reward) received from pharmaceutical companies.

Professional influence

This is traditionally a key factor for physicians, most of who usually attend conferences, seminars and workshops where they are suggested to prescribe a particular medicine by opinion leaders.⁶ The effect of social communication and leaders of opinion on prescription behavior has been well documented.²⁷ Although this influence is not directed by the company, its potential effect on prescriptions is of great important. Hence, in the pharmaceutical context, marketing efforts are mostly performed through these leaders of opinion to generate a multiplier effect. There is a study that has quantified the impact of social communication and peer effects on physicians’ behavior, and the study concluded that this behavior is greatly affected by the attitude and the practices of opinion leaders.⁶ Therefore, the fifth hypothesis is formulated as follows:

H5. Prescription loyalty is positively related to the level of professional influence.

Accessibility and affordability of drugs

Access is defined as having medicines continuously available and affordable at public or private health facilities. Although theoretically literature demonstrates that physicians are not price sensitive, they are usually asked by patients and public healthcare organizations to control pharmaceutical costs by selecting the cheaper medicines which are cost-effective. In addition, insurance policies to reimburse medicines have a great effect on physicians’ prescription behavior over time. In other words, people with insurance coverage not only fill more prescriptions, but they are likely to have access to more expensive therapies as well. Physicians’ sensitivity to price would be different in different contexts; for instance, physicians working in the Spanish NHS are greatly sensitive to the price that can be afforded by patients.²⁸ In contrast, physicians show fairly limited price sensitivity in the USA.⁹ Finally, physicians’ tendency to prioritize patient convenience can affect their prescription behavior; therefore, our sixth hypothesis is as follows:

H6. Prescription loyalty is positively related to the level of drug accessibility.

Methods

Instrument development

The six measures explained earlier, was used to develop the instrument of the study. The participants were asked to mark the extent of their agreement on the Likert scale from 1 (strongly disagree) to 5 (strongly agree). The initial questionnaire was delivered to 10 specialist physicians and 5 marketing professors to judge face and content validity. All the received comments were taken into account within the final questionnaire.

Data collection

The data were gathered in six months from a cross-sectional survey conducted in 2015. One thousand of 35,000 physicians were selected randomly from the Iranian medical council registry database and were invited via phone to participate in this research, where 437 of them accepted our invitation. This sample provides an adequate sample size based on the Cochrane equation. The questionnaires were delivered to the 437 physicians by a research team and were completed during previously arranged meetings. Descriptive and inferential statistics were performed on collected data using SPSS 17.0.0.

Results

Of these 1000 invited physicians, the 437 participants completed the questionnaire, and Table 1 shows their demographic profile.

Table 1.

Demographic profile of the participants

Title	Category	Frequency (%)
Age (years)	25–35	20.9
	36–45	41.4
	46–55	29.2
	56–65	6.5
	>65	2
Gender	Male	59.5
Gender	Female	40.5
Specialty field	Internist	45.8
	Podiatrist	14
	Cardiologist	13
	Psychiatrist	11.8
	Dermatologist	10.01
	Oncologist	6.2
	Neurologist	5.1
Experience (years)	1–10	37.6
	11–20	44.2
	21–30	11.8
	31–40	6.4
Average prescription/day	1–15	32.5
	16–30	40.1
	31–45	14.5
	46–60	12
	More than 60	0.9
Workplace	Private sector	77.3
Workplace	public sector	22.7

All the questionnaire items in each measure were analyzed to test the convergent and discriminant validity. The results of validity testing are illustrated in Table 2. The correlation between the items with the construct is represented by factor loading. The Eigen values that should be greater than 1 represent the standardized variance associated with a particular factor.²⁹ Concerning discriminant validity, approach was used to evaluate this validity.³⁰ For being discriminant validity, the AVE for each construct should be higher than the squared correlation between the construct and any of the other constructs, which results indicated that all measures have a suitable validity.

Table 2.

Descriptive and factor analysis of measures

Measures	Mean (SD)	KMO	AVE	Factor loading	t-value
PSR professional values	3.3 (0.58)	0.88	66.1	64–72%	3.30
Drug quality	3.9 (0.43)	0.85	67.5	48–79%	2.89
Corporate reputation	3.6 (0.62)	0.79	66.6	67–76%	7.63
Promotional tools	3.9 (0.39)	0.77	65.6	63–79%	0.53
Professional influence	3.7 (0.67)	0.71	68.95	60–73%	6.14
Accessibility and affordability	3.4 (0.64)	0.76	58.4	68–77%	4.56

With respect to convergent and discriminate validity and to achieve higher AVE, some questions having to do with PSR professional values (three questions), drug quality (two questions), professional influence (two questions), corporate reputation (one question), and promotional tools (one question) are omitted. Finally, the presented items in Table 3 were used for further analysis. Reliability analysis shows that the assessment tool produces stable and consistent results using the alpha coefficient.³¹ Table 3 provides some information regarding reliability and descriptive analysis of the items for each measure.

Table 3.

Reliability and descriptive analysis of the items

Measure	Questions	Mean(SD)	Cronbach's alpha
PSR professional values	PSRs contributes to brand loyalty through presenting scientific evidence	3.52 (0.88)	0.72
	Professional behavior of PSRs influences brand loyalty	3.46 (0.88)
	PSRs influence brand loyalty by frequent visits	3.00 (0.92)
	Shared interests and concerns with PSRs influence brand loyalty	2.95 (0.96)
Drug quality	Drugs’ less adverse reactions lead to brand loyalty	4.42 (0.71)	0.75
	Drugs’ effectiveness leads to brand loyalty	4.15 (0.86)
	Drugs with high quality material leads to brand loyalty	4.09 (0.90)
Corporate reputation	Brand loyalty is influenced by company’s image	3.32 (0.98)	0.67
	Company’s credit and experience in the field of represented drug influence brand loyalty	3.72 (0.92)
	Company’s archaism in the market affects brand loyalty	3.68 (0.83)
Promotional tools	Company’s rewards promote brand loyalty	2.26 (0.95)	0.69
	Company’s support for conferences and travels facilitates brand loyalty	2. 43 (0.88)
	Drugs’ advertising in websites and journals affects brand loyalty	3. 14 (0.97)
Professional influence	Positive clinical experiences of other physicians with a brand lead to brand loyalty	4.34 (0.67)	0.75
	Key opinion leaders influence brand loyalty	4.11 (0.83)
	Well-known drugs in the market encourage brand loyalty	4.09 (0.99)
Accessibility and affordability	Insurance coverage of a drug leads to brand loyalty	4.12 (0.85)	0.74
	Patients’ affordability toward a drug influences brand loyalty	4.22 (0.80)
	Low cost of a drug promotes brand loyalty	3.60 (0.78)
	Availability of a drug in the market influences brand loyalty	4.04 (0.83)

Structural equation model

Structural Equation Modeling technique is a common approach to test the proposed research hypotheses particularly in social, management, behavioral, biological, and educational sciences. In this regard, we use LISREL 8.54 software to test our hypotheses. The LISREL path modeling estimates both factor loadings and path coefficients simultaneously.¹¹ The fitting indexes—showing how well a model is developed and verified—in our model all are acceptable which are presented in Table 4. This clearly implies that the developed model has enough validity to show a relationship between latent and visible variables. The developed model according to the SEM technique, is shown in Figure. 2.

Table 4.

Goodness-of-fit measures

Fitness indicator	Suggested criteria	Validation value	Result
Absolute fit indicators
C²/df	3>	2.8	Compliant
GFI	0.90<	0.93	Compliant
RMR	0.05>	0.04	Compliant
RMSEA	<0.05–0.08	0.04	Compliant
Incremental fit indicators
AGFI	0.90<	0.94	Compliant
NFI	>0.90	0.93	Compliant
CFI	0.90<	0.95	Compliant
IFI	0.90<	0.93	Compliant
Goodness of fit index
PNFI	>0.5	0.08	Compliant
PGFI	>0.5	0.07	Compliant

Figure 2.

Structural model of physicians’ loyalty. PL: prescription loyalty; PSR: PSR professional values; Qual: drug quality; Rep: corporate reputation; PT: promotional tools: Pro: professional influence: Acce: accessibility.

Based on the developed model, professional influence and promotional tools have the highest and lowest effects on brand loyalty, respectively. Corporate reputation and drug quality are the second and the third influencing factors.

Hypothesis testing

Hypotheses are tested based on values and significance levels (t-value) of each measure in Table 2, as the t-values greater than +1.96 and lower than −1.96 are considered significant.³² As can be seen in Table 2, brand loyalty is significantly affected by all the measures except promotional tools. PSR professional values, drug quality, corporate reputation, professional influence, and accessibility positively impact prescription loyalty in a way that supports our hypotheses.

Discussion

Brand loyalty is becoming a major concern among policymakers and has been a popular component of pharmaceutical marketing in the past decades. As the matter of fact, having loyal customers, that is, physician and consumer, is the most desirable objective of such companies competing in the pharmaceutical market. To this end, pharmaceutical companies, particularly innovator ones, do their best to launch the products that have greater chance to grasp the attention of the customers mentioned above. Taking the importance of this issue into account, we could find few studies addressing factors affecting physicians’ loyalty to prescribe a given medicine.

Iran is a large country with a great market in the pharmaceutical context, which provides an interesting market with multinational companies in order to sell their products.³³ In this regard, during the past decades, numerous foreign companies have been trying to push their products into this market by using a variety of tools. Therefore, this motivated the authors to investigate why physicians might be loyal to a defined medicine in their real practice.

In this study, six hypotheses were developed to investigate those factors that affect brand loyalty. Although H1 was supported by the results of this study, placing PSRs professional values as the last significant factor is nevertheless in contrast with what was found in other studies.³ As scientific and professional standards of PSRs professional values may vary between different markets, it is expected that their effects would not be same in different contexts. In other words, PSRs cannot be trusted by physicians if they are not professional enough and well educated in their specialty. Previous studies suggested that trust of the salesperson can be transferred to the supplier firm and vice versa.^16,34 This means that as the company reputation may be affected by PSRs’ professional values, it would be pivotal for branded companies to pay more attention to selecting qualified PSRs and to train them continuously.

In line with other studies,⁸ we found drug quality an important and significantly affecting factor in prescription behavior. Therefore, H2 was approved. Kennedy et al. expressed that quality products result in customer trust in both salespeople and manufacturer and, as a result, loyalty is made.³⁵ Quality consists of a wide range of features, among which having more efficacy and fewer side effects are of great importance compared with others, mainly because these are two of the things that are most desirable for physicians in selecting a suitable medicine. Although the generic medicines’ manufacturers claim the same quality with their competitors, physicians do not perceive this factor same across competing pharmaceutical companies in the market. As a consequence, they rely on what they experience in the real world rather than on a mere claim.

In addition, we found corporate reputation the second significantly influencing factor on prescription loyalty; hence, H3 was accepted. Corporate reputation is a worthy intangible asset in pharmaceutical firms and they can use it as a unique competitive advantage to compete with others. Dick and Basu³⁶ stated that a good impression of a firm can result in having loyal customers to support and repurchase the company products. As far as loyalty to a medicine is concerned, corporate reputation has a potential effect on physicians’ behavior and physicians’ loyalty to a given medicine, so much so that it can substantially alter the view of physicians that all products of a company are worth prescribing. Therefore, it is critical for pharmaceutical companies to do the activities that enhance their reputation such as maintaining quality products, following business ethics, following international standards, and showing their responsibility toward societies.

Unlike previous studies,^3,5,9,37 surprisingly our result showed that promotional tools do not lead to brand loyalty in Iran when they are with other factors and it is a non-significant factor as well. This result did not support H4. However, this does not mean Iranian physicians do not consider promotional tools important at all. This result reveals that at the moment of prescribing, physicians do not observe tangible rewards as a paramount variable in their prescription behavior. This finding also implies that pharmaceutical companies in Iran should focus their efforts mostly on providing non-financial rewards to physicians rather than financial ones because generally they have high incomes and may not be responsive to these kinds of incentives. Of course, there are strong regulations on physicians accepting tangible rewards in many countries, like the USA. Based on Keller³⁸ view, companies need to understand that tangible rewards can no longer be a point of difference; hence, they have to focus far more on PSR professional values.

Moreover, according to the results of this study, professional influence has the most positive effect on Iranian physicians to remain committed to the drugs of a particular company. Therefore, H5 is accepted in this study while this is a quite controversial result among studies in this issue.³ In addition, Iranian physicians are deeply under the impression of their own positive experience of medicines and are more interested in getting information about them from different sources, other than PSRs. One of these sources is key opinion leaders, which is taken into account by Nair et al.⁶ They have focused on opinion leaders’ effects on physician prescription behavior in their study and have found that this significantly influences physician prescription choices. This point can be fundamental for pharmaceutical companies in paying more attention to opinion leaders when they design marketing activities in general and detailing in particular. It is well understood that in any professional field of healthcare, there are some key persons who have broad knowledge in that profession and they remarkably influence the direction of the profession both domestically and internationally. Typically, physicians’ role, as key opinion leaders, has increasingly been popular over the world in that they have a great, priceless role in promoting pharmaceutical products in markets. Therefore, it is greatly supposed that policy makers set documented regulations in this matter in order to reduce the adverse effects of such professional interactions.

Finally, accessibility is the last influencing factor which was taken as effective factor in the creation of prescription loyalty by Iranian physicians, and H6 was accepted. In a study, Valcarcel et al. have concluded that Spanish physicians are price sensitive in making decisions to prescribe.²⁷ This factor may be considered important by physicians in the prescription process wherever drugs are not accessible or affordable. In other words, physicians would rather in general prescribe the medicines that are accessible and affordable for patients. By doing so, they would ensure that patients’ adherence to treatment is increased. The greater adherence to treatment patients have, the more desirable outcomes they will achieve, and the more satisfied physicians will become. Therefore, companies should pay high attention to price setting and supply-chain efficiency to provide continuous access their medicines to societies.³⁹

Limitations

The results may not be generalized to other contexts on account of the limited sampling location. The results may be specific to the Iranian context with its regulation, health system, health insurance and culture. In addition, response bias in sample (if any) could not be evaluated due to lack of published data on demographic and other related characteristics of the studied population.

Conclusion

This study provides an empirical model for prescription loyalty behavior in Iran as an emerging pharmaceutical market. Our empirical investigation of prescription loyalty among Iranian physicians showed that all the assumed factors significantly affect prescription loyalty except promotional tools such as tangible rewards. In addition, the least effect is shown by PSR professional value. Therefore, based on these the results, the companies should revise their marketing strategy as both PSRs’ professional values and tangible rewards were not seen to be very effective in prescription loyalty.

Furthermore, professional influence by peer physicians was shown to be the highest factor contributing to brand loyalty, which was followed by corporate reputation. Therefore, attention to corporate reputation and key opinion leaders are the most effective strategies contributing to brand loyalty if they are balanced by reasonable price and an efficient supply chain.

Ethical approval

Ethical approval is not applicable for this type of study. However, following ethical concerns, a comprehensive description about the study was introduced to the participants in the first page of the questionnaire and they were allowed to reject answering or withdrawing at any time thereafter. The participants were assured that their answers would be kept confidential and that their names would not be disclosed during the study and in the final report.

Footnotes

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Author biographies

Gholamhossein Mehralian is an Assistant Professor in Pharmacoeconomics and Pharma Management at the Shahid Beheshti University of Medical Sciences, Tehran, Iran. He received his PharmD and PhD in Pharmacoeconomics and Pharma Management from Shahid Beheshti University of Medical Sciences, Tehran, Iran. His research interests are Pharmaceutical outcome & policy, Pharmaceutical innovation, Corporate social responsibility, Social Pharmacy, and Pharmaceutical supply chain, particularly by focusing on healthcare industries. He has published more than 35 papers in peer-reviewed journals. Mehralian is the corresponding author and can be contacted at: gmehralian@gmail.com

Zahra Sharif is a PhD Candidate at the school of pharmacy of Shahid Beheshti University of Medical Sciences. Sharif is a pharmacis and her research interests include Pharmaceutical Innovation, Pharmaceutical Outcome & Policy, and Social Pharmacy. Her research appears in numerous international journals.

Nazila Yousefi is a PhD Candidate at the school of pharmacy of Shahid Beheshti University of Medical Sciences. Yousefi is a pharmacis and has MS degree on Public Health: MPH. Her research interests include Pharmaceutical Innovation, Pharmaceutical Outcome & Policy, and Social Pharmacy. Her research appears in numerous international journals.

Mahdi Akhgari is a PhD Candidate at ASPER School of Business, University of Manitoba, Canada.

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