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3.4.3 Transparency and Reporting of Research Results

Recommendation All trials should be prospectively registered in public databases.

Registration offers transparency regarding promising stem cell-based interventions so that patients, regulators, and the scientific community can monitor these efforts and incorporate them into future efforts, thereby minimizing risk and maximizing benefits of clinical trials. Registration also promotes integrity in scientific research, such as ensuring that scientists do not change primary endpoints after studies commence or otherwise take steps that might compromise the quality of research data. In addition, registration promotes access to clinical trials for patients who might not otherwise have a means of knowing about them. However, having a trial listed on public databases does not necessarily mean that the trial has been vetted by regulators or is in compliance with these guidelines. Prospective patients or their representatives should always confirm that trials are authentic before enrolling.

Adverse Event Reporting
Recommendation Investigators should report adverse events, including their severity and potential causal relationship with the experimental intervention.

Knowing the safety profile of stem cell-based interventions is critical for effective translation. Timely analysis of safety information is also crucial for reducing the uncertainties surrounding stem cell-based interventions. Unfortunately, many studies report deficiencies in adverse event reporting for novel therapeutics (Saini et al., 2014). Researchers should report adverse events associated with cells, procedures, and all other aspects of the intervention. Most if not all national regulatory agencies mandate the reporting of such events, as they would for any clinical trial, and thus trials of stem cells should do the same at all trial phases. 

Recommendation Researchers should promptly publish results regardless of whether they are positive, negative, or inconclusive. Studies should be published in full and according to international reporting guidelines, including registration in the public databases.

Publication of all results and analyses, regardless of whether an agent is advanced to further translation or abandoned, is strongly encouraged to promote transparency in the clinical translation of stem cell-based therapies, to ensure the development of clinically effective and competitive stem cell-based therapies, to prevent individuals in future clinical trials from being subjected to unnecessary risk, and to respect research subjects’ contribution (Fung et. al 2017). As such, reporting must be timely and accurate with the ambition to report long term follow up as well for those therapies where the agent is predicted to survive long term. Publication of data without paywalls is encouraged. Researchers should also consider ways to share individual research subject data, provided that adequate privacy protections for research subjects can be assured. A U.S. Institute of Medicine Report offers principles on sharing clinical trial data (Institute of Medicine, 2015). Researchers, sponsors, and others should adhere to these principles. Additional information is also available from the AllTrials initiative (, which the ISSCR supports. 

If a particular project can be described according to internationally recognized reporting guidelines, this format should be used. For example, researchers should report all randomized trials according to the CONSORT statement recommendations (Consolidated Standards of Reporting Trials; Journal editors should accommodate publication of inconclusive and disconfirmatory findings. See also Section 4, Communications. Publications should also be included in the clinical trial registries to allow easy access to the outcome of the trial.