Search

Open, prospective registration of a study protocol can improve research rigour in a number of ways. Through preregistration, key features of the study's methodology are recorded and maintained as a permanent record, enabling comparison of the completed study with what was planned. By recording the study hypothesis and planned outcomes a priori, preregistration creates transparency and can reduce the risk of several common biases, such as hypothesising after results are known and outcome switching or selective outcome reporting. Second, preregistration raises awareness of measures to reduce bias, such as randomisation and blinding. Third, preregistration provides a comprehensive listing of planned studies, which can prevent unnecessary duplication and reduce publication bias. Although commonly acknowledged and applied in clinical research since 2000, preregistration of animal studies is not yet the norm. In 2018 we launched the first dedicated, open, online register for animal study protocols: wwwpreclinicaltrialseu. Here, we provide insight in the development of preclinicaltrials.eu (PCT) and evaluate its use during the first 3 years after its launch. Furthermore, we elaborate on ongoing developments such as the rise of comparable registries, increasing support for preregistration in the Netherlands-which led to the funding of PCT by the Dutch government-and pilots of mandatory preregistration by several funding bodies. We show the international coverage of currently registered protocols but with the overall low number of (pre)registered protocols., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY. Published by BMJ.)

Objectives: The ultimate goal of biomedical research is the development of new treatment options for patients. Animal models are used if questions cannot be addressed otherwise. Currently, it is widely believed that a large fraction of performed studies are never published, but there are no data that directly address this question., Methods: We have tracked a selection of animal study protocols approved in the University Medical Center Utrecht in the Netherlands, to assess whether these have led to a publication with a follow-up period of 7 years., Results: We found that 60% of all animal study protocols led to at least one publication (full text or abstract). A total of 5590 animals were used in these studies, of which 26% was reported in the resulting publications., Conclusions: The data presented here underline the need for preclinical preregistration, in view of the risk of reporting and publication bias in preclinical research. We plea that all animal study protocols should be prospectively registered on an online, accessible platform to increase transparency and data sharing. To facilitate this, we have developed a platform dedicated to animal study protocol registration: www.preclinicaltrials.eu., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.)

Background: Commonly used strategies for cell delivery to the heart are intramyocardial injection and intracoronary (IC) infusion, both having their advantages and disadvantages. Therefore, alternative strategies, such as retrograde coronary venous infusion (RCVI), are explored. The aim of this confirmatory study was to compare cardiac cell retention between RCVI and IC infusion. As a secondary end point, the procedural safety of RCVI is assessed., Methods: Four weeks after myocardial infarction, 12 pigs were randomised to receive mesenchymal stromal cells, labelled with Indium-111, via RCVI (n=6) or IC infusion (n=6). Four hours after cell administration, nuclear imaging was performed to determine the number of cells retained in the heart both in vivo and ex vivo. Procedure-related safety measures were reported., Results: Cardiac cell retention is significantly lower after RCVI compared with IC infusion (in vivo: RCVI: median 2.89% vs IC: median 13.74%, p=0.002, ex vivo: RCVI: median 2.55% vs IC: median 39.40%, p=0.002). RCVI led to development of pericardial fluid and haematomas on the frontal wall of the heart in three cases. Coronary venous dissection after RCVI was seen in three pigs, of which one also developed pericardial fluid and a haematoma. IC infusion led to no flow in one pig., Conclusion: RCVI is significantly less efficient in delivering cells to the heart compared with IC infusion. RCVI led to more procedure-related safety issues than IC infusion, with multiple cases of venous dissection and development of haematomas and pericardial fluid collections., Competing Interests: Competing interests: WAG, MvdN, KN, JPGS, PAD and SAJC report grants from the Netherlands CardioVascular Research Initiative (CVON): the Dutch Heart Foundation, Dutch Federations of University Medical Centers, the Netherlands Organization for Health Research and Development, and the Royal Netherlands Academy of Sciences, during the conduct of the study. JPGS reports grants from Horizon2020 ERC-2016-COG EVICARE, grants from Technobeat, grants from the Project SMARTCARE-II of the BioMedicalMaterials institute, co-funded by the ZonMw‐TAS program, grants from the Dutch Ministry of Economic Affairs, Agriculture and Innovation, during the conduct of the study. WAG, FJvS and SAJC report non-financial support from Cook Regentec, 1102 Indiana Avenue Indianapolis, USA, during the conduct of the study. Catheters for RCVI were provided by Cook Regentec, 1102 Indiana Avenue Indianapolis, USA. On-site training with these catheters was facilitated by Cook Regentec. The authors did not receive payment from Cook Regentec to perform this study. Neither do the authors have stock options in Cook Regentec. Cook Regentec reviewed the manuscript prior to submission. BRvK, AET and JLMB declare no conflict of interest., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY. Published by BMJ.)