Evidence-based medicine in bovine, equine and canine reproduction: Quality of current literature

What Kinds of Dogs Are Used in Clinical and Experimental Research?

Simple Summary

The objective of this study was to evaluate the signalment of dogs used in veterinary research in six different specialties. In total, 150 randomly chosen clinical studies (25 studies per specialty) published between 2007 and 2019 were evaluated for the breed, sex, neuter status, age, and weight information of the dogs used. Breed information was given for 5.7% of the included animals. Beagles were used 1.9% of the time, which was a less significant role in research than we expected. Information about the sex of the dogs was lacking for 16.2% of the included animals, while age and weight information were missing for 22.7 and 32.7%, respectively. The neuter status was not given in 38.7% of the clinical studies. The results show deficits in the reporting of demographic data for the dogs. The need for an improvement in the documentation and/or reporting of animal signalment is obvious and should be addressed by authors, reviewers, and journal editors in the future.

Abstract

Background: Dogs are widely used in research to answer questions about canine or human conditions. For the latter, research dogs are often used as models, since they are physiologically more similar to humans than other species used in research and they share similar environmental conditions. From a veterinary perspective, research findings are widely based on academic research, and thus are generated under experimental conditions. In that regard, the question arises: do the dogs used for research adequately represent the dog population seen in veterinary practice? It may, for example, be assumed that Beagle dogs are often used as experimental animals. The objective of this study was to evaluate the signalment of dogs used in veterinary research. Furthermore, we aimed to assess other relevant criteria regarding the validity of clinical trials in the context of six different veterinary medicine specialties: cardiology, internal medicine, neurology, orthopaedics, reproduction, and surgery. Methods: A literature search was conducted and 25 studies per specialty were randomly selected. The breed, sex, neuter status, median age, and median weight of the dogs used for clinical studies (n = 150) published between 2007 and 2019 were evaluated. Results: In total, 596,542 dogs were used in the 150 trials. Breed information was given for 33,835 of these dogs (5.7%). Of the latter, 1.9% were Beagles. Nine clinical trials exclusively used Beagles. The most frequently used breeds were German Shepherds (7.3%), Labrador Retrievers (6.7%), and Golden Retrievers (4.7%). The major reporting deficits found were missing breed specification in 25.3% of the articles; missing information about the sex of the dogs in 16.2%; missing age and weight information in 22.7 and 32.7%, respectively; and missing neuter status in 38.7% of the clinical studies. The median sample size was 56 (Q1:29; Q3:365) dogs. Conclusions: The presented project revealed that Beagle dogs represent only a small proportion of dogs in veterinary research. Based on the evaluated publications, it seems that some relevant dog attributes differ between the specialties. The results, however, show deficits in the reporting of demographic data for the dogs. The need for an improvement in the documentation and/or reporting of animal signalment is obvious and should be addressed by authors, reviewers, and journal editors in the future.

Study design quality of research on dogs published in peer-reviewed journals

BACKGROUND

In the past it has been criticised that only a low proportion of well-designed and well-reported studies in some medical specialities is available. The objective of this study was to systematically evaluate the quality of literature about canine medicine published in peer-reviewed journals in relation to six specific veterinary medicine specialities.

METHODS

A literature search was conducted and 25 studies per speciality were selected. The quality of the articles (n = 150) published between 2007 and 2019 was evaluated with a validated checklist.

RESULTS

In articles related to all specialities, deficits were found, such as not adequate number of animals in 60.0% of the studies. In 88.0%, information about housing and feeding of the dogs were not specified. In 69.4% of the prospective clinical studies, an ethical approval was reported, and written informed consent of the owners was obtained in 46.2%.

CONCLUSIONS

The findings revealed extensive deficits in the design and reporting of studies in canine medicine. The demand for improvement is obvious and should be addressed by authors, reviewers and journal editors in the future. Our results underline that practitioners should critically appraise the quality of literature before implementing information into practice.

Improving decision-making in complicated or rare cases-An approach towards Evidence-based Veterinary Medicine in small animal reproduction

The concepts of Evidence-based Veterinary Medicine (EBVM) provide a methodological and systematic approach to include the best evidence from research into clinical decision-making. These concepts include steps as the search and assessment of relevant research findings and consideration of individual aspects. In addition, owners and other persons involved in animal health care should be included in shared decision-making. Some breeders have good basic knowledge concerning breeding management and characteristics of diseases and concerning advantages and disadvantages of different therapeutic approaches, while others are notable to understand complex medical interrelations or emergency situations. All these aspects need to be addressed when communicating and discussing different diagnostic, prophylactic and therapeutic options. In special fields, such as small animal reproduction, veterinarians often see animals with rare diseases or complex conditions so that an application of standard therapies and well-established textbook recommendations is not possible. To learn more about cases too rare for successful systematic research, the case collection tool REPROCASES (www.evssar.org/reprocases) is now available. The aim of this project is to gather information from specialists on small animal reproduction in a multicentre approach. If you see rare or not well-investigated cases such as cystic ovarian diseases, cryptorchidism or others, you are more than welcome to share your findings via the database. Even if this approach cannot completely replace standardized clinical trials, the idea is to gather more information on effects, prognosis, side effects and long-term fertility for specific conditions.

Teaching Evidence-Based Veterinary Medicine in the US and Canada

There is no comprehensive review of the extent to which evidence-based veterinary medicine (EBVM) is taught in AVMA-accredited colleges of veterinary medicine in the US and Canada. We surveyed teaching faculty and librarians at these institutions to determine what EBVM skills are currently included in curricula, how they are taught, and to what extent librarians are involved in this process. Librarians appear to be an underused resource, as 59% of respondents did not use librarians/library resources in teaching EBVM. We discovered that there is no standard teaching methodology nor are there common learning activities for EBVM among our survey respondents, who represent 22 institutions. Respondents reported major barriers to inclusion such as a perceived shortage of time in an already-crowded course of study and a lack of high-quality evidence and point-of-care tools. Suggestions for overcoming these barriers include collaborating with librarians and using new EBVM online teaching resources.

Evidence-based Medicine in Animal Reproduction

With new knowledge being generated and published daily, the importance of evidence-based approaches in veterinary medicine is obvious. Clinicians must stay current or risk making poor decisions that clients may challenge. Especially in animal reproduction, several new substances and procedures to diagnose or treat reproductive disorders have been introduced in the last years. On the other hand, a closer look at the quality of published literature on animal reproduction reveals major deficits in methodology and reporting of many clinical trials. We strongly recommend systematically assessing the quality of scientific information when reading journal papers before using the given information in practice. The aim of evidence-based medicine (EBM) is to base the decisions in the practice of medicine on valid, clinically relevant research data. Therefore, we suggest that students should become familiar with the concepts of evidence-based veterinary medicine (EBVM) at the beginning of their veterinary education. Concepts and supporting tools such as checklists for literature assessment have been developed and validated. The purpose of this article is to review and discuss the importance of incorporating EBVM in animal reproduction. The need for further research that produces strong evidence in different fields of animal reproduction and better reporting of relevant study information is obvious.

A survey of the awareness, knowledge, policies and views of veterinary journal Editors-in-Chief on reporting guidelines for publication of research

BACKGROUND

Wider adoption of reporting guidelines by veterinary journals could improve the quality of published veterinary research. The aims of this study were to assess the knowledge and views of veterinary Editors-in-Chief on reporting guidelines, identify the policies of their journals, and determine their information needs. Editors-in-Chief of 185 journals on the contact list for the International Association of Veterinary Editors (IAVE) were surveyed in April 2012 using an online questionnaire which contained both closed and open questions.

RESULTS

The response rate was 36.8% (68/185). Thirty-six of 68 editors (52.9%) stated they knew what a reporting guideline was before receiving the questionnaire. Editors said they had found out about reporting guidelines primarily through articles in other journals, via the Internet and through their own journal. Twenty of 57 respondents (35.1%) said their journal referred to reporting guidelines in its instructions to authors. CONSORT, REFLECT, and ARRIVE were the most frequently cited. Forty-four of 68 respondents (68.2%) believed that reporting guidelines should be adopted by all refereed veterinary journals. Qualitative analysis of the open questions revealed that lack of knowledge, fear, resistance to change, and difficulty in implementation were perceived as barriers to the adoption of reporting guidelines by journals. Editors suggested that reporting guidelines be promoted through communication and education of the veterinary community, with roles for the IAVE and universities. Many respondents believed a consensus policy on guideline implementation was needed for veterinary journals.

CONCLUSIONS

Further communication and education about reporting guidelines for editors, authors and reviewers has the potential to increase their adoption by veterinary journals in the future.

Therapy of bovine endometritis with prostaglandin F2α: a meta-analysis

The objective of the conducted meta-analysis was to assess the efficacy of the treatment of bovine endometritis with PGF(2α) by statistical means. Postpartum uterine infections have a high prevalence and a very negative effect on reproductive performance in dairy cattle. Because of a wide discordance between research results, a meta-analysis of the efficacy of the treatment of bovine endometritis with PGF(2α) was conducted. A comprehensive literature search was performed using online databases to reveal a total of 2,307 references. In addition, 5 articles were retrieved by reviewing citations. After applying specific exclusion criteria and evaluating specific evidence parameters, 5 publications, comprising 6 trials, were eligible for being analyzed by means of meta-analysis. Data for each trial were extracted and analyzed using meta-analysis software Review Manager (version 5.1; The Nordic Cochrane Centre, Copenhagen, Denmark). Estimated effect sizes of PGF(2α) were calculated on calving to first service and calving to conception interval. Prostaglandin F(2α) treatment of cows with chronic endometritis had a negative effect on both reproductive performance parameters. Heterogeneity was substantial for calving to first service and calving to conception interval [I(2) (measure of variation beyond chance)=100 and 87%, respectively]; therefore, random-effects models were used. Sensitivity analysis as well as subgroup analysis showed that the performance of randomization was influential in modifying effect size of PGF(2α) treatment. The funnel plot illustrated a publication bias toward smaller studies that reported a prolonged calving to conception interval after a PGF(2α) treatment. We conclude that the investigation of this subject by means of meta-analysis did not reveal an improvement of reproductive performance of cows with endometritis after treatment with PGF(2α). Furthermore, there is a shortage of comparable high quality studies investigating reproductive performance after PGF(2α) treatment of cows with chronic endometritis.

A critical evaluation of diagnostic methods used to identify dairy cows with acute post-partum metritis in the current literature

The overall objective of this study was to investigate how relevant research publications address the validity of diagnostic methods for acute puerperal metritis (APM) in dairy cows, a disease commonly treated with antibiotic drugs. Therefore, a literature search was conducted in Journal of Dairy Science, Theriogenology, Animal Reproduction Science and The Veterinary Journal utilizing the ScienceDirect database. The search revealed 259 articles addressing APM. After applying exclusion criteria, a total of 48 trials remained. It was determined whether the author gave a clear definition of APM, the time of diagnosis relative to calving, and the person who performed the diagnosis. Studies were checked for the presence of definitions of possible findings, thresholds, and test characteristics of the methods used. Overall 9 different diagnostic methods were employed. On average 2·5 ± 1·75 diagnostic methods were used in a study. References to support the use of the diagnostic methods were provided in 10 of 48 articles (20·8%). Vaginal discharge, transrectal palpation and rectal temperature were examined in 39, 22, and 21 of the studies, respectively. Thresholds for diagnostic tests and test characteristics were mentioned in 6 and 3 of the 48 articles, respectively. Based on this systematic review of 48 research papers the evidence supporting the use of the diagnostic methods to identify cows with APM has either been not reported or is weak. In conclusion, the reporting of the diagnostic methods to identify cows with APM needs to be improved and further high-quality research is necessary to improve diagnostic performance of the methods employed.

Evidence-based medicine: quality and comparability of clinical trials investigating the efficacy of prostaglandin F2α for the treatment of bovine endometritis

The objective of this study was to evaluate the quality and comparability of published literature, and to summarize the effect of prostaglandin F2α (PGF2α) for the treatment of endometritis. It has been postulated that there is a dearth of high-level evidence-based research results in veterinary medicine. Also, there is a marked variation in the quality of studies in veterinary and animal science. Post-partum uterine infections occur commonly in dairy cattle and are reported to have a negative impact on reproductive performance. A comprehensive literature search was conducted utilizing online databases revealing a total of 2723 references. After applying specific exclusion criteria, a total of 68 trials were eligible for further analysis. These articles were evaluated utilizing specific parameters listed in an evaluation form such as randomization and the involvement of control groups. The analysis revealed that more than half of the trials (51·5%) were at least 20 years old. Furthermore, we found that about one third (36·8%) of all trials were controlled and randomized, while 3 of those (4·4%) were also blinded. Of those trials which calculated a calving-to-conception interval (n=30), 50% of the authors claimed an improvement, which was statistically significant in 23·3% of the cases. We conclude that there is a wide discrepancy between research results investigating the efficacy of PGF2α.

Inter-observer agreement on a checklist to evaluate scientific publications in the field of animal reproduction

This study's objective was to determine respondents' inter-observer agreement on a detailed checklist to evaluate three exemplars (one case report, one randomized controlled study without blinding, and one blinded, randomized controlled study) of the scientific literature in the field of bovine reproduction. Fourteen international scientists in the field of animal reproduction were provided with the three articles, three copies of the checklist, and a supplementary explanation. Overall, 13 responded to more than 90% of the items. Overall repeatability between respondents using Fleiss's κ was 0.35 (fair agreement). Combining the "strongly agree" and "agree" responses and the "strongly disagree" and "disagree" responses increased κ to 0.49 (moderate agreement). Evaluation of information given in the three articles on housing of the animals (35% identical answers) and preconditions or pretreatments (42%) varied widely. Even though the overall repeatability was fair, repeatability concerning the important categories was high (e.g., level of agreement=98%). Our data show that the checklist is a reasonable and practical supporting tool to assess the quality of publications. Therefore, it may be used in teaching and practicing evidence-based veterinary medicine. It can support training in systematic and critical appraisal of information and in clinical decision making.