Developers' Handbooks

Ver. Release Date View Download Release Notes Forum Links
2.6 April 29, 2023 Digital Copy, v2.6
  • New informational section on Review and Endorsement of AOP-Wiki Content added (page 8).
    • Section provides basic information on ways to request peer review of content developed in the AOP-Wiki, and potentially added to the OECD workplan and considered for endorsement.
  • New informational section on Content Licensing added (page 9).
    • Provides an overview of the license options that can be applied to AOP, Event, and Relationship pages in the AOP-Wiki, and rules/restrictions related to changing license selections over the course of AOP development.
  • Author status and SAAOP status fields eliminated from the AOP-Wiki and Handbook.
    • Author status has been replaced with relevant licensing options.
    • SAAOP status was not being actively used and has been eliminated.
  • Coach(es) field was added (page 15).
    • Identification of coaches provides acknowledgement of the volunteer contributions made by the coach(es) and professional recognition.
  • Handbook Version was added to the “Status” table on the AOP pages (page 15).
    • The users can select the version of the AOP Handbook that was used to guide their AOP development.
    • This provides coaches, technical peer-reviewers, and users awareness of the guidance that was followed during development.
    • Authors are not required to update their AOPs based on the most current version of the Handbook, they need only comply with the Handbook version that corresponded to the date of creation of their AOP in the AOP-Wiki, or newer.
Handbook v2.6 change notes.pdf
2.5 July 15, 2022 Digital Copy, v2.5
  • Added section to define the AOP development strategy
  • Stressors replace with Prototypical Stressors
  • Guidance for Evidence Collection Strategy for Key Event Relationships
  • Guidance for describing modulating factors for Key Event Relationships and AOPs
  • Introduced tabular format for summarizing evidence supporting essentiality of Key Events
  • Guidance for discussing potential applications of AOPs
2.0 February 14, 2018 AOP_Handbook_release_2018.pdf

OECD (2018), "Users' Handbook supplement to the Guidance Document for developing and assessing Adverse Outcome Pathways", OECD Series on Adverse Outcome Pathways, No. 1, OECD Publishing, Paris,

1.0 September 25, 2014 AOP_Handbook_September_25_2014_release.pdf

This document is a supplement to the Guidance Document for developing and assessing Adverse Outcome Pathways (AOPs) [ENV/JM/MONO(2013)6] (AOP guidance hereafter). The AOP Guidance, published in 2013, only one year after the OECD programme on the development of AOPs was initiated, was considered a first version which would be revised as expert groups and member countries gained experience in developing and assessing AOPs. This handbook contains an updated template for AOP development and provides focused and practical instructions for both AOP developers and reviewers and is intended to assist in identifying, organising and evaluating critical information on key events (KE) as well as linkages between KEs within the AOP (i.e., AOP development). It also provides more evolved and explicit guidance on how to assess the weight of evidence (WOE) (degree of confidence) supporting the overall AOP and its relevance for life stage, sex and taxonomy (i.e., AOP evaluation). The handbook is intended to be used as a supplement to the AOP guidance and a replacement for the AOP Template (Part II of the guidance) and evaluation for which improvement was needed.