Invited review: Completeness of reporting of experiments: REFLECTing on a year of animal trials in the Journal of Dairy Science

Abstract

Reproducibility is an essential element of the scientific process, and it requires clear and complete reporting of study design, conduct, and analysis. In the human and animal health literature, incomplete reporting is associated with biased effect estimates. Moreover, incomplete reporting precludes knowledge synthesis and undervalues the resources allocated to the primary research. The Reporting Guidelines for Randomized Controlled Trials for Livestock and Food Safety (REFLECT) statement, published in 2010, is a checklist developed by expert consensus to provide guidance on what study elements should be reported in any intervention trial (designed experiment) involving livestock. The Journal of Dairy Science (JDS) has recently endorsed the use of reporting guidelines. To assess the status of reporting of controlled experiments in JDS and to provide a baseline for future comparison, we evaluated the reporting of 18 items from the REFLECT statement checklist in a sample of 137 controlled trials published in JDS in 2017. Two reviewers independently screened titles and abstracts for relevance and then evaluated a sample of 120 papers reporting controlled trials (experimental studies involving at least one intervention and one comparison or control group), using yes or no questions. Although some items, such as treatment details and statistical analysis, were well reported, other areas, including sample size justification, allocation concealment, blinding, study flow, baseline data, and ancillary analyses, were often not reported or were incompletely described. This work highlights the need for authors and reviewers to take advantage of guidelines and checklists for reporting. Adherence to reporting guidelines can help improve the completeness of reporting of research, expedite and better inform the peer-review process, increase clarity for the reader, and allow for knowledge synthesis, such as meta-analysis, all of which serve to increase the value of the work conducted.

Comparative efficacy of antimicrobial treatments in dairy cows at dry-off to prevent new intramammary infections during the dry period or clinical mastitis during early lactation: a systematic review and network meta-analysis

“…There is evidence that reporting of randomization has improved since the publication of reporting guidelines such as the REFLECT statement (Totton et al ., 2018). However, reporting specific to dairy science revealed that although 104 of a sample of 137 trials published in 2017 reported random allocation to study group, only seven reported the method of randomization (Winder et al ., 2019). Assumptions for many statistical methods rely on interchangeable groups, and failure to randomize has been shown to be associated with exaggerated treatment effects (Burns and O'Connor, 2008; Sargeant et al ., 2009 a ; Brace et al ., 2010).…”

Comparative efficacy of antimicrobials for treatment of clinical mastitis in lactating dairy cattle: a systematic review and network meta-analysis

“…A lack of reporting key design features is consistent with recent evaluations of animal health research (Totton et al, 2018;Winder et al, 2019), and a lack of reporting has been associated with exaggerated treatment effects (Wellman and O'Connor, 2007;Sargeant et al, 2009aSargeant et al, , 2009b. Not only do deficiencies in The upper right-hand section of the table represents the risk ratio between the numerator (upper left treatment) and denominator (lower right treatment).…”

A systematic review of the efficacy of antibiotics for the prevention of swine respiratory disease

“…In this review, although there were trials where allocation to the intervention group was not random, the more common issue was trials where the authors referred to allocation as ‘random,’ but did not provide a description as to how the allocation sequence was generated, counter to recommended reporting standards (Schulz et al ., 2010; O'Connor et al ., 2010 a ). Failure to report key features related to the potential for bias were also noted in this review, which is consistent with other publications which have evaluated the quality of reporting in livestock trials (Wellman and O'Connor, 2007; Burns and O'Connor, 2008; Sargeant et al ., 2009 a , 2009 b ; Brace et al ., 2010; Winder et al ., 2019). Some study characteristics were also not well reported in the trials included in this review, such as month of study conduct and location of the study.…”