Introduction: Certain methodological principles should be inexcusably followed when designing clinical or observational research to avoid bias and presentation of results that do not reflect the truth about the phenomenon that is the object of the study. Aim: The aim of this study was to compare the methodological quality of clinical trials and observational studies published in medical journals from ex-Yugoslav countries indexed in Pubmed/MEDLINE. Methods: Clinical studies published in medical journals of ex-Yugoslav countries were retrieved from the Pubmed/MEDLINE database, and the sample for analysis was randomly chosen from the retrieved publications. The rate of the most common errors in the design of clinical/observational studies was established by a careful reading of the sampled publications and their checking against predefined criteria. Results: The studies published in two countries that are now member states of the European Union (Slovenia and Croatia) have significantly higher citation rates, impact factor, and methodological quality scores than studies from other ex-Yugoslav countries. While publications from Croatia show clear improvement trend throughout the last two decades, which is visible also in the last 10 years in Slovenia and Bosnia and Herzegovina, quality of clinical research published in journals from Serbia was stagnating in the same period. Conclusions: There are significant differences in methodological quality and scientometric characteristics of clinical research published in medical journals of ex-Yugoslav countries that could be mitigated by more intensive training of clinical researchers in statistics and research design, as well as by more rigorous editorial practices.

Introduction: COVID-19 is the disease caused by an infection of the SARS-CoV-2 virus, previously known as 2019 Novel Coronavirus (2019-nCoV) respiratory disease. World Health Organization (WHO) declared the official name as COVID-19 in February 2020 and in 11th March 2020 declared COVID-19 as Global Pandemic. In June 6th 2020, over 7 million cases registered in the world, recovered 3.4 million and death over 402.000. Aim: The aim of this study is to retreive published papers about COVID-19 infection deposited in PubMed data base and analyzed current results of investigations regarding morbidity and mortality rates as consequences of COVID-19 infection and opinions of experts about treatment of afected patients with COVID-19 who have Cardiovascular diseases (CVDs). Methods: It’s used method of descriptive analysis of the published papers with described studies about Corona virus connected with CVDs. Results: After searching current scientific literature (on PubMed till today is deposited more than 1.000 papers about COVID-19 with consequences in almost every medical disciplines), we have acknowledged that till today not any Evidence Based Medicine (EBM) study in the world. Also, there are no unique proposed ways of treatments and drugs to protect patients, especially people over 65 years old, who are very risk group to be affected with COVID-19, including patients with CVDs. Vaccine against COVID-19 is already produced and being in phases of testing in praxis in treatment of COVID-19 at affected patients, but the opinions of experts and common people whole over the world about vaccination are full of controversis. Conclusion: Frequent hand washing, avoiding crowds and contact with sick people, and cleaning and disinfecting frequently touched surfaces can help prevent coronavirus infections are the main proposal of WHO experts in current Guidelines, artefacts stored on a web site. Those preventive measures at least can help to everybody, including also the patients who have evidenced CVDs in their histories of illness. Authors analyzed most important dilemmas about all aspects of CVDs, including etipathogenesis, treatment with current drugs and use of potential discovered vaccines against COVID-19 infection, described in scientific papers deposited in PubMed data base.

Introduction: COVID-19 is the disease caused by an infection of the SARS-CoV-2 virus, first identified in the city of Wuhan, in China’s Hubei province in December 2019. COVID-19 was previously known as 2019 Novel Coronavirus (2019-nCoV) respiratory disease before the World Health Organization (WHO) declared the official name as COVID-19 in February 2020. Aim: The aim of this study is to search scientific literature in the biomedicine and analyzed current results of investigations regarding morbidity and mortality rates as consequences of COVID-19 infection of Cardiovascular diseases (CVD), and other most common chronic diseases which are on the top mortality and morbidity rates in almost all countries in the world. Also, to propose most useful measures how to prevent patients to keep themselves against COVID-19 infection. Methods: We used method of descriptive analysis of the published papers with described studies about Corona virus connected with CVD, and, also, Guidelines proposed by World Health Organization (WHO) and European Society of Cardiology (ESC), and some other international associations which are included in global fighting against COVID-19 infection. Results: After searching current scientific literature we have acknowledged that not any Evidence Based Medicine (EBM) study in the world during last 5 months from the time when first cases of COVID-10 infection was detected. Also, there is no unique proposed ways of treatments and drugs to protect patients, especially people over 65 years old, who are very risk group to be affected with COVID-19. Expectations that vaccine against COVID-19 will be produced optimal during at least 10 months to 2 years, and in all current Guidelines most important proposed preventive measures are the same like which one described in Strategic documents of WHO, in statements of Declaration of Primary Health Care in Alma Ata in 1978. Conclusion: WHO proposed preventive measures can be helpful to everybody. Physicians who work at every level of Health Care Systems, but especially at primary health care level, must follow those recommendations and teach their patients about it. But, the fact is that current focus of COVID-19 epidemic has targeted on protection of physical health of population in global, however, the influence on mental health which will be one of the important consequences of COVID-19 pandemic in the future, and which could be declared as «Post-coronavirus Stress Syndrome„ (PCSS) could be bigger challenge for Global Public Health.

Introduction: Results of preclinical and clinical studies in medicine could be trusted only if their design and statistical analysis were appropriate. Aim: The aim of our study was to investigate whether preclinical and clinical studies published in medical journals of Bosnia and Herzegovina satisfy basic requirements for appropriate design and statistical interpretation of data. Methods: Preclinical and clinical studies published in medical journals of Bosnia and Herzegovina were retrieved from the PubMed database, and the sample for analysis was randomly chosen from the retrieved publications. Implementation rate of basic principles of experimental design (local control, randomization and replication) and rate of the most common errors in design of clinical/observational studies was established by careful reading of the sampled publications and their checking against predefined criteria. Results: Our study showed that only a minority of experimental preclinical studies had basic principles of design completely implemented (7%), while implementation rate of single aspects of appropriate experimental design varied from as low as 12% to as high as 77%. Only one of the clinical/observational studies had none of the errors searched for (2%), and specific errors rates varied from 10% to 89%. Average impact factor of the surveyed studies was around one, and average publication date recent, less than 5 years ago. Conclusion: Prevalence of preclinical studies that did not follow completely basic principles of research design, and that of clinical/observational studies with errors are high, raising suspicion to validity of their results. If incorrect and not protected against bias, results of published studies may adversely influence future research.

Committee of Publishing Ethics (COPE) announced great problem with retraction of the papers published in journals which are cited in Web of Science data base, before and after retractions from the journals were papers published, because of unethical behaviours of the authors - https://retractionwatch.com/the-retraction-watch-leaderboard/top-10-most-highly-cited-retracted-papers/ (1).