A core goal of the journal is to promote the transparency and collective usability of published articles to the fullest extent possible. To this end – in addition to publishing articles in open access – we implement the following measures.

• As a rule, data and materials must be made publicly available. Exceptions must be explained in a comprehensible and justifiable way when submitting a manuscript and this statement will be included in case of publication.
• Pre-registration of hypotheses, study plans, and analysis strategies is recommended. When submitting a manuscript, authors must clearly state whether their study(ies) has/have been preregistered and conducted according to the pre-registration. This statement will be included in case of publication.
• We award Open Science Badges for Open Data, Open Materials, and Pre-registration.
• We enable and welcome the submission of Registered Reports.
• Individual contributions by the authors as well as any sources of funding and conflicts of interest must be stated explicitly. This statement will be included in case of publication.
• All comments by the reviewers and the corresponding responses by the authors will be included in case of publication.

Open Science Badges

To increase the visibility of open-science practices, EPO awards Open Science Badges where justified. We currently award the following badges:

• Preregistered
• Open Materials
• Open Data

Badges are awarded based on the disclosure procedure, that is, authors are invited to provide public statements affirming achievement of badge criteria and they are accountable for the accuracy of their statements. We or the reviewers will not necessarily verify if the sharing of data and materials or any pre-registrations meet the badge criteria.

We will do a cursory evaluation of any data, materials, or pre-registrations, that is, we will test if the provided links lead to the respective components and if the linked materials are related to the submitted report. If authors think that a badge is warranted although the badge criteria are not met completely, they should provide a concise justification. We will review the plausibility of such justifications.

What do authors have to do to apply for Open Science Badges?

1. Please read the criteria for Open Science Badges, developed by the Center for Open Science.
2. Remove those badges that do not apply to your submission from the margin next to the heading Open-science statement in the manuscript template.
3. Ensure that your open-science statement clarifies why the remaining badges are warranted. To this end, please provide the following information:

For the Preregistered badge

• Provide the URL, DOI, or other permanent path to the pre-registration in a public, open access repository. The pre-registration needs to be time-stamped.
• Was the plan registered prior to examination of the data? If no, please explain.
• Were there additional registrations for the study other than the one reported? If yes, provide links and explain.

For the Open Materials badge

• Provide the URL, DOI, or other permanent path for accessing the materials in a public, open access repository.
• Is there sufficient information for an independent researcher to reproduce the reported methodology? If no, explain.

For the Open Data badge

• Provide the URL, DOI, or other permanent path for accessing the data in a public, open access repository.
• Is there sufficient information for an independent researcher to reproduce the reported results? If no, explain.