A world map of evidence-based medicine: Density equalizing mapping of the Cochrane database of systematic reviews

Are popular books about diet and health written based on scientific evidence? A comparison of citations between the USA and Japan

OBJECTIVES

To describe and compare the references cited in popular books about diet and health between the USA and Japan.

DESIGN

Books were selected based on their best-seller rankings in the diet and health category of online bookstores. We identified references throughout all pages of the books and examined the number of references, reference format (identifiable or not) and presence of specific types of references, such as systematic reviews of human research. We compared the characteristics of references between the two countries and examined related factors to citation.

SETTING

Cross-sectional study.

PARTICIPANTS

Books (n 100 in each country).

RESULTS

Among 100 books from each country, sixty-five US and sixty-six Japanese books had references. Forty-five US books cited more than 100 references, against only five Japanese books. The number of books that cited systematic reviews of human research differed between the USA (n 49) and Japan (n 9). Additionally, the number of books that provided identifiable information for all references was significantly higher in the USA (n 63) than in Japan (n 42). Books whose first authors have licences of medical doctors were more likely to cite references than those without in both countries.

CONCLUSIONS

Two-thirds of books about diet and health cited references in both the USA and Japan, but Japanese books cited fewer references and were less likely to cite systematic reviews and provide identifiable references than US books. Further research into the scientific reliability of information in books about diet and health is warranted.

Teaching evidence-based medicine in Mexico: a systematic review of medical doctor curriculums at a national level

OBJECTIVES

To assess the teaching of evidence-based medicine (EBM) in medical curriculums. As a secondary objective, we assessed the representativeness of science courses related to EBM.

DESIGN AND SETTING

Systematic review. Accredited curriculums by the Mexican Council for the Accreditation of Medical Education.

MAIN OUTCOME MEASURES

We provided a descriptive analysis of the required or elective EBM courses and EBM-related courses, academic credits and teaching period. EBM-related courses included research methodology, epidemiology, biostatistics, clinical research, public health, clinical epidemiology, scientific dissemination and health informatics to explore scientific education and training offered by medical schools. Additionally, we examined the curriculum's structure, location, type of institution, total programme duration and academic credits. Data collection occurred from December 2020 to February 2021.

RESULTS

We identified 171 registered curriculums, of which we assessed 60 unique programmes (50% public) in our analysis. We identified 16 EBM single courses on the fifth and sixth semesters, of which 12 (20%) were mandatory and 4 were electives (6.7%). The allocated academic credits for EBM courses are minimal, without difference between public or private institutions, representing 0.08% of the total curriculum. Public health, epidemiology, research methodology and biostatistics courses are offered with greater frequency (55% or less) and curricular value (0.6% or less). In some cases, they are taught as combined courses. Clinical research, health informatics and clinical epidemiology are taught less than EBM, while scientific dissemination is nil.

CONCLUSION

In Mexico, EBM teaching is limited to only one of five curriculums with minimal curricular value. A comprehensive curricular review is necessary across programmes to incorporate EBM as a first step to improve medical education and, consequently, public health. We call to action through an online, collaborative platform with several applications to optimise teaching of EBM.

REVIEW PROTOCOL REGISTRATION

The systematic review protocol is excluded from the International Prospective Register of Systematic Reviews since this platform only accepts systematic reviews with health-related outcomes. Review protocol registration: https://osf.io/3xm2q/.

A comparison of systematic reviews and guideline-based systematic reviews in medical studies

The question of how citation impact relates to academic quality accompanies every decade in bibliometric research. Although experts have employed more complex conceptions of research quality for responsible evaluation, detailed analyses of how impact relates to dimensions such as methodological rigor are lacking. But the increasing number of formal guidelines for biomedical research offer not only the potential to understand the social dynamics of standardization, but also their relations to scientific rewards. By using data from Web of Science and PubMed, this study focuses on systematic reviews from biomedicine and compares this genre with those systematic reviews that applied the PRISMA reporting standard. Besides providing an overview about growth and location, it was found that the latter, more standardized type of systematic review accumulates more citations. It is argued that instead of reinforcing the traditional conception that higher impact represents higher quality, highly prolific authors could be more inclined to develop and apply new standards than more average researchers. In addition, research evaluation would benefit from a more nuanced conception of scientific output which respects the intellectual role of various document types.

Microbiome research in general and business newspapers: How many microbiome articles are published and which study designs make the news the most?

The microbiome is a matter of interest for science, consumers and business. Our objective is to quantify that interest in academic journals and newspapers, both quantitatively and by study design. We calculated the number of articles on the microbiome from the total number of biomedicine articles featured in both PubMed and Spanish science news agency SINC, from 2008 to 2018. We used the Factiva database to identify news stories on microbiome papers in three general newspapers (The New York Times, The Times and El País) and three business newspapers (The Wall Street Journal, the Financial Times and Expansión), from 2007 to 2019. Then, we compared news stories with microbiome papers in PubMed, while also analyzing the frequencies of five study design types, both in the newspapers and in the papers themselves. Microbiome papers represented 0.8% of biomedicine papers in PubMed from 2008 to 2018 (increasing from 0.4% to 1.4%), while microbiome news published by SINC represented 1.6% of total biomedical news stories during the same period (increasing from 0.2% to 2.2%). The number of news stories on microbiome papers correlated with the number of microbiome papers (0.91, p < 0.001) featured in general newspapers, but not in business ones. News stories on microbiome papers represented 78.9% and 42.7% of all microbiome articles in general and business newspapers, respectively. Both media outlet types tended to over-report observational studies in humans while under-reporting environmental studies, while the representation of systematic reviews of randomized controlled trials, randomized controlled trials and animal/laboratory studies was similar when comparing newspapers and PubMed. The microbiome is receiving increasing attention in academic journals and newspapers. News stories on the microbiome in general and business newspapers are mostly based on research findings and are more interested in observational studies in humans and less in environmental studies compared to PubMed.