According to Audit standards, internal controls affect the Auditor’s reliance on collected Auditing evidence and the process of determining the type, nature, and timing of engagement and the range of Audit methods. This research aims at exploring the effects of internal controls quality on Audit report lag on the firms enlisted in Tehran Stock Exchange. To this end, the research data for the period after the enactment of internal controls instructions, during the years from 2012 to 2015 were analyzed. The results indicate a significant, positive relationship between internal control weaknesses and Audit report lag. In other words, not weakness in internal controls is associated with punctual Audit report. The research findings provide empirical evidence regarding the common viewpoint in Audit standards, based on which internal controls affect the process of determining the timing of Audit engagement.

This study examines the effects of of Audit firms’,mergers on Audit report lag (ARL). The sample includes 946 firm-years listed on Tehran Stock Exchange and Iran’, s Fara Bourse (OTC) for the period 2011 to 2020 and the difference-in-differences (DID) estimation technique is used. The results show that the Audit firms’,mergers have no significant relationship with the ARL of these firms. This result is robust for several sensitivity tests. Such a finding indicates that, contrary to the expectations of regulators, in the absence of substantive mergers, it is not possible to imagine the synergy resulting from economies of scale and its consequence in increasing Audit efficiency and reducing ARL. More precisely, the symbolic mergers between Audit firms were done only for the purpose of commercialism and increasing market share, but only the Audit firms benefited from the mergers and shareholders and clients do not benefit from receiving the Audit report in a timely manner. The findings of this study could be useful for regulators to deal with the Audit firms` mergers and perceiving the incentives of mergers phenomena.

Restatements’ of financial statements and consequently Audit failures are surprisingly high in Iran and Audit report lag (ARL) is also falling sharply. Although there are studies about determinations of Audit failure, the role of ARL in Audit failure by taking into account the possible moderating role of family ownership has not been investigated. One of the factors that affects Auditors’ ability in detecting breaches in clients’ financial statements is Audit effort. Hence, it can be predicted that ARL, as a surrogate of Audit effort, has a negative relation with Audit failure. The results of multivariate analysis reveal that ARL has a negative and significant relation with Type II Audit failure, but there is no significant association between ARL and Type I Audit failure. Moreover, family ownership is positively associated with Type I Audit failure and it has an insignificant relation with Type II Audit failure. Finally our findings show that family ownership does not moderate the relation between ARL and Type II Audit failure.

Objective: Due to the expansion of societies and economic and commercial issues, the demand for financial and economic information has increased and the financial statements of companies that contain this information are of great importance to users. This information is effective on people's decisions when it is reported at the right time, otherwise some of them lose their economic value. The timely submission of financial statements depends on the completion period of the Audit process, as financial statements cannot be released before the Audit is completed. The duration of annual Audit is stated as one of the most important factors determining the timeliness of financial reporting of companies. The delay in submitting the Audit report reduces the credibility and quality of financial reporting. According to previous researches, the timely presentation of financial reports enriches the content of information, which affects the value of the company. Considering that the reporting of financial information is delayed until it is not Audited by independent Auditors, the Auditing of financial statements by external independent Auditors is very important, because Audited financial statements are considered to be the most important reliable sources for investors and their users. It can be said that financial statements Audited by external independent Auditors are the only and best source for external users. The issue of delay in providing the Audit report is significant and vital for external users because faster access to information is effective in their optimal decision-making and also increases the possibility of earning profit. The purpose of this study is to apply a meta-analysis approach to combine and analyze contradictory findings from various studies to investigate the effect of characteristics and accounting complexity criteria of the company on the Audit report lag. Methods: The current research is applied research in terms of classification based on the goal, and descriptive-meta-analytical in terms of nature and method. Meta-analysis is a research approach that helps the researcher to achieve a suitable combination of the quantitative results of contradictory and non-contradictory studies in the past, to explain the contradictions and to identify the structural variables that moderate the results of the past studies. Meta-analysis basically follows the steps of a scientific research and has almost the same steps as quantitative research, with the difference that here the sampling unit is a study instead of a subject, and because it is actually a combination of data from several studies to produce a single estimate, therefore, from a statistical point of view, It is considered a type of multi-factorial method. The community under investigation of this research is internationally published authoritative articles (A*, A, B, C) in the list of 2019 (ABDC) and domestic authoritative articles approved by the Ministry of Science, Research and Technology. In order to achieve the purpose of the research using Lipsey & Wilson (2001) method and also Cochran’s Q test and Egger test, a total of 77 studies including 20 internal studies during 2010 Up to 2019 and 57 foreign studies during the years 1989 to 2019 were reviewed. In these researches Audit report lag was considered as a dependent variable and the characteristics of the Organizational complexity as an independent variable. CMA2 software is used in meta-analysis in order to perform the necessary calculations, including calculating the effect size, after collecting the desired variables from the relevant research. Results: The results of this study shows that there is a negative relationship between the firm size and the Audit report lag, while other characteristics, extraordinary items, subsidiary, merger or acquisition, foreign sales, restatement of financial statements and Business segments of the company have a positive relationship with the Audit report lag. Conclusion: Considering the expansion of accounting and Auditing knowledge and the importance of providing timely information for financial and economic decisions, the factors that cause delays in the submission of Audit reports and ultimately Audited financial statements are very important. The delay in submitting the Audit report causes an imbalance in the level of access of users to financial information, which can ultimately affect the capital market transactions and the value of the company. The conclusion of the present meta-analysis showed that one of the complexity criteria used in most studies is the size of the company. Larger companies, with more resources and facilities, seek for faster Auditing and reduce delays in the Audit report. It can also be stated that the existence of other criteria related to the complexity of the company will lead to the expansion of the Audit process and increase the delay in submitting the Audit report.

The purpose of this research is to use the meta-analysis approach to analyze and combine the conflicting and inconsistent results obtained in past researches in the field of investigating the effects of the characteristics of companies on the Audit report lag. Company characteristics include company size, company profitability, company age, Company loss and company leverage. In the research conducted in the past years, the Audit report lag is known as the dependent variable and the specific characteristics of the companies as the independent variable. To achieve the research objectives from the approach [28] and also, to apply Cochran-Egger’s Q tests, Including 77 studies including 27 domestic studies during the years 2013 to 2022 and 50 foreign studies during the years 2010 to 2023 were reviewed. The results indicate that there is no significant relationship between the size of the company and the independent Audit report lag, But there is a negative relationship between profitability, age and the independent Audit report lag, Also, there is a positive relationship between the leverage and the loss of the company with the Audit report lag.

Objective: The purpose of this study is to use a meta-analysis approach to analyze and combine inconsistent results of past researches on the impact of the Auditor and Auditrelated features on the Audit report lag. These variables include the Auditing firm size, Auditor industry specialization, Auditor change, the Audit tenure, type of Auditor report and Auditor busy season Methods: in order to achieve the purpose of the research using Lipsey & Wilson (2000) method and also Cochran’ s Q test and Egger test, a total of 75 studies including 20 internal studies during 2010 Up to 2019 and 55 foreign studies during the years 1989 to 2019 were reviewed. In these researches Audit report lag was considered as a dependent variable and the characteristics of the Audit firm as an independent variable. Results: The results show that there is no significant relation between Audit firm size and the Auditor tenure with Audit report lag. While Auditor change, type of Auditor report, and Auditor busy season have a positive relation with Audit report lag. Finally, there is a negative relation between Auditor industry specialization and Audit report lag. Conclusion: The specialized Auditors in companies can speed up the Audit process and make financial reports available to users with less Audit lag. also to reduce Audit report lag, firms should reduce the Auditor change and first-year Audit and Provide the necessary infrastructure to reduce material misstatements in corporate financial statements and the publishing of qualified report by Auditors, which leads to Timely publish of financial statements that enriches the content of information.

Power, as one of the characteristics of CEO, can play a significant role in corporate decisions about financial reporting. If CEO use power in line with their interests, their power will be problematic and affect the Audit time of the company. Thus, the present study aimed to investigate the effect of CEO power on Audit report lag using Hansen's threshold regression approach. The research sample included 150 companies listed on the Tehran Stock Exchange during 2011-2018. This study was applied and the research hypothesis was tested using the threshold regression analysis. The results of testing the research hypothesis indicated that the CEO power has a negative effect on Audit report lag in the companies where the CEO power is lower than the threshold limit while the power of CEO has a positive effect on Audit report lag in the companies where the CEO power is higher than the threshold limit.

The primary purpose of conducting the above research is to use the meta-analysis approach to prove whether past researches provide a consistent picture of the drivers of Audit report delays or not. These variables include; The independence of the board of directors, the size of the board of directors, the size of the Audit committee, the independence of the Audit committee, the financial expertise of the Audit committee, the number of meetings of the Audit committee, and the duality of the CEO. To achieve the goal of the above research, the approach of Lipsey and Wilson (2001) was used and also, and the implementation of Cochran and Egeer's Q tests including 9 domestic articles and 19 foreign studies during the years 2010 to 2023 was investigated. The results showed that there is no significant relationship between the size of the board of directors and the size of the Audit committee, the independence of the Audit committee, the number of meetings of the Audit committee, and the duality of the CEO with the ARL. However, there is a significant negative relationship between the board of director's independence and the Audit committee's financial expertise. The activity of expert Auditors in the Audit committee can speed up the Audit process of companies and ensure that financial statements reach users on time. In addition, shareholders can take the main step toward timely financial statements by electing an independent board of directors.