The Implementation of Tax Indirect Auditing Methods in Greek Economy Against Tax Evasion

Abstract

This article aims to review and analyse the indirect auditing methods that were applied in Greece for the first time at the beginning of 2012 as a tax auditing tool, for the more comprehensive identification of taxable items. By employing the use of indirect auditing methods (mark-up method, net worth method, source and application of funds method, unit & volume method and bank deposits and cash expenditure method) an attempt is made to determine withheld taxable items, other than those measured by the tax forms and the official accounting books and taxpayers’ tax data, by utilizing the information from various sources and bodies.

At the same time, a survey was carried out, on a randomly selected sample of 517 respondents, for analysing the awareness of Greek taxpayers regarding the use of indirect auditing methods as well as the general population’s awareness of their basic tax obligations. A total of 96.13% of the population were not aware of indirect audit methods while 79.88% expressed the belief that being aware of them can potentially increase citizens’ tax compliance. The survey highlighted that regarding indirect tax audit methods the level of knowledge of the general population is very low, necessitating the organized and systematic promotion of these new methods by the Tax Authority, which can lead to the disclosure of withheld (shadow) taxable items and thus achieve greater tax compliance in the long term.

Keywords

Tax Evasion Indirect Methods Tax Audits Shadow Economy

Introduction

General Remarks

Indirect audit methods are internationally acclaimed practices that enable the tax authorities, alongside traditional audit methods that focus on the data derived from accounting records and tax returns, to more effectively capture any undeclared taxable items, while obtaining and utilizing information on the financial status and behaviour of taxpayers, from other external sources, such as financial institutions, insurance organizations, investment management organizations, mortgage companies, transport/postal services companies, public utility bodies of electricity, water, natural gas, private educational institutions/schools, tourist agencies, and so on.

The use and the importance of indirect audit methods in the context of tax audits has been the subject of analysis by international organizations such as the Organization for Economic Cooperation and Development (OECD), the International Monetary Fund (IMF), the European Organization of Tax Services (Intra-European Organization of Tax Administrations—IOTA) (OECD, 2006; Rettig, 2014).

The aim of this article is to determine the degree of citizens’ awareness of the indirect audit methods, and how the level of this awareness, could affect (or not) their tax compliance.

Background

Since the 1950s, the United States Tax Administration has used indirect methods as a key tool against tax evasion. After all, based on the study in question, as early as 1954, the U.S. Supreme Court noted that indirect methods have been instrumental in securing public revenues (Duke, 1966; Taylor, 1955). Increasingly, governments are resorting to the use of indirect methods for determining withheld tax items to reduce tax evasion and increase government revenues by collecting the attributable taxes and fines (Botha, 2009; Davis-Culler et al., 2021; Dugan & Taylor, 2020; Eisenberg, 2018).

Above all, the significance of indirect methods and their emerging importance has been demonstrated through the shared experience of tax authorities internationally and in the international literature (Branko, 2017; Bucci, 2019; IRS, 2023a; Retting, 2011; Rettig, 2014; Schatan et al., 2020; Smith, 2015; Stasinopoulos, 2022b; Vo et al., 2020; Wise, 2000).

Meanwhile, certain concerns have been expressed on the rightful and rational access of tax authorities to all kinds of information that does not infringe upon individuals’ fundamental rights and sensitive data. The existing legislation should provide the administration with wide powers to collect information, and exploitation of Big Data but at the same time offer safeguards on the protection of individuals’ fundamental rights and freedoms (Biber, 2010; Stasinopoulos, 2022a,b).

Choice of the Indirect Audit Method

Indirect audit methods were first introduced in the Greek law under the Law no. 4038/2012 and were amended to the provisions of the Income Tax Code (Law 2238/94) by Article 67B of Law. Specifically, these provisions state that: The determination of results by audit may also be carried out by applying one or more of the following audit methods:

the analysis of the taxpayer’s liquidity (source & application of funds method),

the taxpayer’s net worth (net worth method),

the amount of bank deposits and cash expenditure (bank deposits and cash expenditure method),

the principle of ratios (mark-up method),

the ratio of selling price to the total turnover (unit & volume method).

The same methods were included in the provisions of the new tax laws passed in 2013 (Article 27 of Law 4174/2013) in the context of the modernization of the Greek tax administration. However, for their implementation by the Tax Authority, specific conditions that were set out in the provisions of Article 28 of Law 4172/2013 (Income Code) must be met. Also, a series of Decisions and Regulatory Acts were issued by the Greek Tax Authority in order to determine the implementation details by auditors (IAPR, 2013).

Indirect Methods Share on Total Tax Audits

In recent years, as illustrated in Table 1, there has been an increase in the use of indirect methods (still at a low percentage) by the Greek Tax Administration.

Table 1.

Number of Indirect Audit Methods in Greece.

Results of Tax Audits	2019	2020	2021	2022
Number of tax audits using indirect methods	N/A	427	686	2,189
Established amounts using indirect method audits (€ million)	N/A	89.27	172.11	624.59
Total number of audits= (Based on general provisions and indirect methods)	20,247	18,239	17,743	17,506
Total amounts established (€ million)	1,466.35	1,629.37	3,325.85	1,559.98
Total amounts recovered (€ million)	404.47	169.79	179.7	197.7

Source: IAPR (2022).

In 2020, the audit centres of the Greek Tax Authority conducted 18,239 tax audits, of which only 427 were carried out using indirect methods. The amounts established from audits in 2020 amounted to €1.6 billion (against an annual target of €1.8 billion), up 11.1% compared to 2019, and the amounts recovered amounted to €169.8 million, down 58% compared to the previous year (€404.5 million). The amounts established from audits based on indirect methods amounted to €89.27 million (IAPR, 2020).

In 2021, audit centres carried out 17,743 tax audits of which only 686 were carried out using indirect methods. The amounts established from audits amounted to €3.3 billion in 2021, compared to €1.6 billion in 2020 (annual target 2021: €1.3 billion). This increase is mainly due to the recovery of approximately €1.4 billion from one audit case in December. Recoveries amounted to €179.7 million in 2021, up 5.9% year-on-year (€169.8 million). The amounts established from audits based on indirect methods amounted to €172.11 million (IAPR, 2021).

In 2022, audit centres carried out 17,506 tax audits of which 2,189 were carried out using indirect methods. The amounts established from audits amounted to €1.56 billion in 2022, compared to €3.3 billion in 2021 (annual target 2022: €1.8 billion). This decrease is mainly due to a specific recovery of approximately €1.4 billion from an audit case in December 2021. Recoveries amounted to €197.7 million in 2022, an increase of 10% compared to the previous year (€179.7 million). The amounts established from controls based on indirect methods amounted to €624.59 million (IAPR, 2022).

A Review of Indirect Audit Methods

In this section, the theoretical framework of indirect audit methods is discussed. The first three methods to be presented (source & application of funds method, net worth method, bank deposits and cash expenditure method) mainly concern natural entities while the next two (mark-up method and unit & volume method) are applicable to legal entities engaged in business activities.

Source and Application of Funds Method

The source and application of funds method involves an analysis of the taxpayer’s cash flows and a comparison of all known expenditures with all known revenues regarding the reference period. Net increases and decreases in assets and liabilities are taken into account along with non-deductible expenses and non-taxable income. The excess of expenses over the sum of reported and non-taxable income is considered as unreported taxable income. This method is based on the theory that any excess in expenditure (capital outlays), compared to revenues (capital resources), represents an underestimation of taxable income (IRS, 2016, 2023c).

This method is used when the taxpayer’s cash assets are not deposited in a bank account from where it is easy to track their source and allocation, or when the expenditures made are disproportionate to the income declared. To apply the method, a balance sheet with two main columns is created.

Sources of Capital/Revenues and Capital/Revenue Outlays

The first column (of the balance sheet, as described above) contains all revenues received during the reference tax period under audit where the realization and legality of transactions is highlighted.

The second column contains all the realized expenditures made during the reference tax period under audit.

The unreported taxable amount is obtained by summation of the amounts of these two columns. If income was properly reported, the revenues received should be equal to the realized expenditures. If, however, the realized expenditures are greater than revenues received, the conclusion drawn is that there is a revenue underestimation or expenditures overestimation. In any case, the difference between revenues received and capital consumed is treated as unreported income and if not properly justified, it is taxed according to the effective provisions.

Net Worth Method

The net worth method is based on the theory that an increase in a taxpayer’s net worth during a fiscal year, after adjustments for non-deductible expenses and non-taxable income, should result from the taxable income of the taxpayer.

This method of the taxpayer’s (physical entity) net worth reconstructs the financial history of the taxpayer by taking into account, for a period of one or more years, all assets and available capital, personal, family or business liabilities, personal, family or business receivables, personal, family or business expenses and even personal and business income, as well as personal, family or business assets and liabilities. The philosophy behind this method is that a tax evader who accumulates wealth in a certain fiscal year will either invest it in assets or spend it or will reduce his liabilities with funds that are not reported as taxable income (OECD, 2006). The purpose of this method is to determine, through a change in the net worth, whether the taxpayer purchases assets (increase in assets), reduces liabilities or makes expenditures with funds not reported as taxable income (Rettig, 2014).

The determination of the taxpayer’s net worth is based on the creation of a balance table for all audited tax periods using as a base tax year the one preceding the first audited tax period, which in fact represents the taxpayer’s financial history. Thus, the first part of the table consists of the assets, and includes all personal, family and business assets of the auditee, his/her spouse and their dependants, as well as deposits in financial institutions at the end of each year.

Assets included in the first part of the above balance sheet are real estate, personal effects of high value, furniture, appliances, other equipment, jewellery and other valuables, miscellaneous receivables, motor vehicles, disposable cash, shares, the end-of-year inventory in the case of a sole proprietorship and miscellaneous accounts or other assets. All the above are recorded in the actual acquisition cost derived from the data available for auditing.

The liabilities part of the balance sheet includes all the liabilities of the audited person’s spouse and his dependants, including professional liabilities, if and only if, they relate to a sole proprietorship. Liabilities include loans from financial institutions, bills and cheques payable and any other demonstrable debt or liability to third parties (creditors) and depreciation. The difference between assets and liabilities is therefore the taxpayer’s net worth for the corresponding tax period. Based on the net worth of each tax period, the initial net worth is deducted in order to produce the net worth table, where for the first year of audit, the initial net worth is the net worth of the base year.

This change in the net worth will be adjusted in cases of acquisition of assets free of charge (e.g., death, donation, gift, parental benefits, lottery winnings, exchanges) and in cases of disposal of assets, with non-deductible personal and family expenses of all kinds (e.g., personal and family living expenses, other expenses, tax-free income from various sources, non-taxable income cases or taxable in a special way), such as income from donations, gains from the sale of assets, grants and other non-taxable cases mentioned or not mentioned in the submitted tax return. The resulting final balance is the determined net income of the audited taxpayer, spouse and dependents, according to the net worth method. This determined taxable amount is then compared with the corresponding declared income from each source. In case of a resulting difference between them, this remains to be verified as unreported income and if not sufficiently documented, it is taxed according to the applicable provisions (Botha, 2009; Eisenberg, 2018; IRS, 2023b).

Bank Deposits and Cash Expenditure Method

The third indirect audit method laid down by the Greek legislation is the bank deposits and cash expenditure method. Based on this method, auditing is carried out by monitoring the movements of the taxpayer’s disposable capital of his/her spouse and dependent members either by deposits in financial accounts or by expenditure in various cash transactions. In essence, this technique analyses the total deposits and assets in financial accounts as well as the purchases and expenditures in cash at business and family level during the audited period and compares them with the total reported income.

The rationale of this method is based on the fact that when a taxpayer receives money, he has three choices: deposit, spend or invest.

This method gives a complete picture of the taxpayer’s trading activities by providing information on the type and amount of deposits, the frequency of these deposits, the entities making these deposits or withdrawals and the credit institutions where these transactions take place.

This method is used when:

the taxpayer makes periodic deposits of money to a bank account which indicates that they are derived from an income-generating activity;

the taxpayer pays most of the business expenses by means of bank cheques.

With this method, taxable income is determined by ‘tracking’ the movement of the taxpayer’s funds and through an analysis of bank deposits, monetary transactions, electronic debits, transfers and credits to bank accounts as well as the taxpayers’ cash expenditure.

The implementation of this method determines the total bank deposits in the audited period. Subsequently, the deposited amounts of the bank accounts relating to non-taxable income are deducted, for instance,

loan disbursement amounts;

compensation transactions between the accounts of the taxpayer, his/her spouse and their dependent members;

transfers and other transactions which do not constitute net deposits.

Payments in cash for professional and business expenses, purchase of commodities, raw and auxiliary materials and other commodities necessary for the exercise of the professional activity, purchases of assets, personal/family expenses, taxes paid, contributions and fines of any kind, repayment/reduction of debts in cash, increases or decreases in disposable cash in the audited period, and any other cash payment are added to the balance of the net bank deposits.

From the new net bank balance, the non-taxable income not deposited into bank accounts, such as loans or donations, is deducted. The resulting balance is adjusted for increases/decreases in accounts receivable and increases/decreases in advance payments received vis-à-vis revenues in subsequent years and is then compared to the total declared income. The resulting recalculated balance, represents, according to this method, the total taxable income. This resulting income is compared to the gross income of the auditee as well as to the total other income of the auditee and his/her spouse. If a positive difference occurs, it is considered and monitored as unreported income and if not sufficiently documented by the auditee–taxpayer, it is taxed according to the existing provisions (Dugan & Taylor, 2020; IRS, 2023d).

The Mark-up Method

Under the ‘mark-up’ principle, the taxpayer’s income is restated using percentages or ratios, which are considered indicative, for the calculation of the actual tax liability. Under this method, an analysis of sales and/or cost of sales is carried out and an appropriate percentage is applied to estimate the taxpayers’ gross income (OECD, 2006).

This method identifies business revenue on the basis of rates and ratios (and in particular on the actual gross profit margin) that are considered reliable, based on generally accepted auditing principles and methods, and are derived either from the enterprise itself or from third-party sources.

For the implementation of the ‘mark-up’ method, after the analysis of sales and/or cost of sales, a reliable ratio is determined and applied to a known, a priori basis (e.g., cost of sales) and thus the taxpayer’s business revenue is determined. The validity of the result of this method is based on the reliability of the ratios used to determine the taxable amount.

The main source of information should be the enterprise itself. Thus, the control to determine the proportions (percentages) to be applied in determining the revenue from business activity makes an exhaustive use of the potential to calculate proportions on the basis of the actual data of the enterprise (costs, expenses, sales prices, and so on), data resulting from the taxpayer’s accounting records on the one hand and from any available data on the other hand, as well as information and clarifications provided either by the auditee himself or by third-party sources (e.g., contractors). Therefore, the actual gross profit margin can be determined by comparing purchase invoices with sales invoices or by analysing price lists or shelf prices or by examining stock records and order books or other relevant information.

In those cases where it is not possible to determine proportions as in the previous case, percentages and ratios may also be derived from data of similar enterprises. In this case, the audit may adjust these percentages and ratios, by taking into account the characteristics of the audited enterprise, in particular the type of commodities, the geographical location of the enterprise, its size, the tax period under audit, the general commercial policy, so that the ratios ultimately applied for the determination of the business revenue correspond to the characteristics of the audited entity.

This method is recommended as an effective one especially in cases where:

the enterprise’s stockpile purchases can be easily allocated to similar groups with the same gross profit rates;

when stockpile (inventory) is the key revenue generator for the enterprise;

when stockpiles originate from a limited and confirmed number of suppliers;

when there is an increased degree of stability in the sales prices charged by the taxpayer.

Unit & Volume Method (The Ratio of Selling Price to Total Turnover)

In many instances, gross receipts may be determined or verified by applying the sales price to the volume of business conducted by the taxpayer. The number of units or volume of business conducted by the taxpayer could be determined from the taxpayer’s books as the records under examination may be adequate concerning the cost of goods sold or the expenses (OECD, 2006).

This method can be used to determine the revenues from business activity by finding the production capacity of an enterprise when the enterprise produces one or more similar products that have a fixed relation between the factors of production (e.g., relation of fabric to the trousers produced) or by determining the volume of turnover when the level of sales is linked to variable costs/operating costs that are proportional to turnover (e.g., relation of packaging to portions of distributed fodder) or by determining the volume of turnover when the level of sales is linked to variable costs/operating costs that are proportional to turnover (e.g., relation of packaging to portions of food distributed, relation of electricity and water supply costs to services provided).

It is noted that the unit & volume method is recommended for the determination of income from business activity when:

The audit can determine the unit selling price and the number of units (products/services) or the volume of transactions based on the cost of goods sold or costs/expenses.

The auditee has limited types of products or certain types of services provided and the prices of sold goods or the fees for services provided remain relatively stable throughout the tax period.

Under the above method, the auditor uses the data at his disposal (purchases of raw materials, price lists, and so on), converts them into products and, on the basis of the prices in the pricelists, draws a conclusion on the gross (revenues) receipts (net of VAT) that the company should have. If those are higher than the gross (revenues) receipts (net of VAT) declared in the tax return, then the difference, if not justified, is taxed.

Presentation of a Survey on the Degree of Awareness of Indirect Methods in the General Population

In the context of this article, the researchers conducted a survey on a sample of the Greek population to determine the degree of awareness of the indirect audit methods applied by the Tax Authority.

Research Material and Methodology

Sample

The survey sample consisted of permanent tax residents of Greece, for the year 2022–2023, who were randomly selected from the telephone directory. Exclusion criteria from the survey were (a) age <18 years, since non-adults do not submit tax return forms, and (b) individuals who in the telephone survey stated that they do not submit tax return forms.

Measurement Tool

A joint questionnaire (via Microsoft Forms and using data from the telephone directory) with multiple-choice type questions was used. The nine questions of the questionnaire (excluding demographic data) were developed upon studying the laws and regulatory acts of the Hellenic Tax Authority regarding the application of indirect audit methods.

It was deliberately decided to include a limited number of questions so as to minimize the burden on the respondents. In a certain question, regarding the evaluation of the benefits of indirect methods, the concept and purpose of indirect audit methods were briefly explained.

Statistical Analysis

The Statistical Package for Social Sciences (SPSS) software, version 27.0.1.0, was used for statistical analysis. The mean value (mean) and standard deviation (SD) were used to describe the normally distributed quantitative variables. For the quantitative variables that are not normally distributed, the median and interquartile range were used to describe the sample. Student’s t-test and Mann–Whitney non-parametric test were applied to compare quantitative variables. Pearson’s ×2 criterion and, when required, Fisher’s exact test were used to compare qualitative variables. Two-tailed significance levels were used, and statistical significance was set at 0.05.

Results

The sample consisted of 517 persons with a mean age of 44.5 years (±1.57 years). Most of the participants were aged between 45 and 50 years (38.8%) and only 17.40% of the sample was aged between 18 and 25 years. A total of 58.02% of the participants were higher education graduates, 26.51% were high school graduates and the remaining 15.47% were primary school graduates.

The majority of the respondents were aware that as taxpayers they are required to submit income tax returns (94.19%), as well as that they comply with their obligation to submit income tax returns regardless of the true or false content (92.26%).

The majority of the respondents employ the services of an accountant to handle their tax affairs (81.23%, n = 420).

A total of 96.13% (n = 497) of the respondents were not aware of what indirect audit methods are.

The majority of the respondents who employ an accountant have not or do not remember being informed by their accountant about indirect audit methods.

In contrast, 82.59% of the sample had heard of the concept of ‘presumptions of subsistence’, while 43.90% were able to explain the function of presumptions of subsistence.¹

401 out of 517 (77.36%) respondents answered that they are cautious about the amounts deposited in banking institutions and avoid depositing or having amounts transferred to them without justification especially after 2010.

In response to the question ‘Do you know what indirect audit methods are?’, the percentage of respondents who answered that they are aware was just 3.87% (n = 20) and the percentage of respondents who are not aware varied by gender, education level and age of the respondents. Persons of higher education institution/technical education institution (AEI/TEI) (p = .0011) and those aged 45 and above (p = .013) were more able to convey the notion of indirect auditing methods (Table 2).

Table 2.

Awareness of Indirect Auditing Methods in Relation to the Respondents’ Demographic Characteristics.

Question	Yes n(%)	No n(%)	p (x² test)
Gender
Male	16	402	.046*
Female	4	95
Education Level
Primary education	2	48
Secondary education	6	141
University Degree	12	308
Age
(Mean value ± SD)			.012** (t = 0.231)
Occupation
Self-employed	14	351
Employee	3	136
Pensioner	1	5
Student	1	3
Other (unemployed, domestic work)	1	2

Notes: * Fisher’s exact test.

**Spearman’s rho test: Higher education institution/Technical education institution (AEI/TEI).

SD: Standard deviation.

Regarding the question ‘Are you aware that being audited by indirect audit methods, can lead to a more honest declaration of income?’, 79.88% of respondents answered YES (see Table 3). It should be noted that in this section of the questionnaire, the researchers provided a brief overview of these methods and concepts. (This was done on purpose and not at the beginning of the questionnaire in order not to influence the initial responses of the respondents.)

Table 3.

Estimation of the Increase in Tax Compliance Upon the Implementation of Indirect Auditing Methods.

Question	Yes n(%)	No n(%)	p (x² test)
Gender
Male	323	95	.046*
Female	90	9
Education Level
Primary education	45	5
Secondary education	120	17
University degree	295	35
Age
(Mean value ± SD)			.012** (t = 0.231)
Occupation
Self-employed	325	40
Employee	130	9
Pensioner	5	1
Student	3	1
Other (unemployed, domestic work)	2	1

Notes: * Fisher’s exact test.

** Spearman’s rho test: Higher education institution/Technical education institution.

SD: Standard deviation.

Finally, the respondents were asked whether indirect auditing methods and the provision of information from third-party sources (such as financial institutions, travel agencies, mortgage offices, utility companies, and so on) make them more sceptical concerning the treatment of their personal data.

The majority 70.01% of respondents (n = 362) answered positively, that is, that they are concerned about the proper management of their personal data.

Discussion on the Survey Results

The most important outcome of this study was that the sample had a low level of knowledge regarding indirect auditing methods since only 9% answered correctly to the question ‘Do you know what indirect auditing methods are?’

The study has shown that indirect auditing methods awareness increases by the age of the participants.

More specifically, male respondents and those who are university graduates were more knowledgeable about the concept of indirect auditing methods than female respondents and those with lower education levels. Also, the educational level of the sample did not appear to be associated with participants’ awareness of indirect auditing methods, although respondents of higher education were more aware than those of secondary or lower education, however, not statistically significant.

The respondents were sceptical about cash deposits in bank accounts for their business affairs. Therefore, taxpayers are aware that the Tax Authority obtains information from third-party sources, and mostly banks rather than any other institutions.

The majority of respondents participating in this survey were aware of their obligation to submit their tax return forms and that they are taxed based on the information reported.

Most respondents employ the service of an accountant; however, they were not informed by their accountant that they can be audited by indirect auditing methods by the Tax Authority or at least they do not remember been informed in general.

Conclusion

The implementation of indirect auditing methods by the Tax Authority is gradually taking precedence among other methods as on the one hand it can provide more effective monitoring and disclosure of withheld tax liabilities, and on the other hand, it requires proper utilization and feedback with data and information from public and non-public bodies. The full digital restructuring, the systematization of process flows, the automatic digital recording of data on a single platform and, above all, the multi-level ‘interoperability’ of the public services involved can become an ‘effective tool’ for the successful implementation of indirect auditing methods. However, the channelling to the Tax Authority of a wealth of information containing valuable financial aspects but in many cases with sensitive information from a wide range of public and private entities raises inevitable issues for the adequate protection of the privacy of individuals, which should be of the utmost concern of the Tax Authority, so as to create a sense of security for taxpayers about the type of information collected and the way it is used by the tax auditors.

The adoption and development of know-how to exploit the increasingly emerging ‘innovative methods of big data analysis’ should become the next research goal in this research field as well as the challenge of the next administrative reform of the state’s audit mechanisms. The creation of a big database with data from all insurance companies, financial institutions, travel agencies, credit card management companies, public utilities, with full monitoring of cash flows and the financial lifestyle of taxpayers is the key factor for both success and failure. This article’s research findings showed that taxpayers’ general awareness of indirect auditing methods is insufficient. Therefore, it is imperative to raise public awareness on the importance of indirect auditing methods not so that taxpayers can ‘hide’ from the Tax Authority, but so that it becomes widely understood that the ‘Tax Authority’ can ‘disclose’ the withheld taxable items. At the same time, accountants must also inform their clients about the new capabilities of the Tax Authority. This is expected to significantly increase taxpayers’ tax compliance.

Footnotes

Acknowledgements

This manuscript has been done within the framework of the Post Doc Programme in Business & Organization Administration of the University of Peloponnese (Greece).

Declaration of Conflicting Interests

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

Funding

The authors received no financial support for the research, authorship and/or publication of this article.

Note

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