Reporting

ARRIVE 2.0 checklist explained

What the ARRIVE 2.0 guidelines ask for when you report animal research, and how to prepare as you go.

The ARRIVE guidelines (Animal Research: Reporting of In Vivo Experiments), revised as ARRIVE 2.0 in 2020, are endorsed by many journals. They are split into the Essential 10, the minimum for a reader to judge reliability, and the Recommended Set, which adds context.

The Essential 10

1. Study design: groups, controls and the experimental unit (animal, cage or litter).
2. Sample size: numbers per group and how the size was decided.
3. Inclusion and exclusion criteria: set in advance; report any animals or data excluded and why.
4. Randomisation: method used to allocate animals to groups.
5. Blinding: who knew the allocation at each stage.
6. Outcome measures: defined, with the primary outcome identified.
7. Statistical methods: tests used, software, and how assumptions were checked.
8. Experimental animals: species, strain, sex, age, weight, source.
9. Experimental procedures: what was done, how, when and where, in enough detail to repeat.
10. Results: summary statistics with a measure of variability, and effect sizes with confidence intervals.

The Recommended Set

Abstract, background, objectives, ethical statement, housing and husbandry, animal care and monitoring (including humane end points), interpretation and scientific implications, generalisability and translation, protocol registration, data access, and declaration of interests.

Prepare while the study runs

• Record the experimental unit and randomisation method on day one.
• Keep an exclusion log with dates and reasons.
• Note who was blinded for each measurement.

PreclinIQ keeps these details with the study and pre-fills an ARRIVE 2.0 checklist and a methods draft for you to review.

Reference: Percie du Sert N, et al. The ARRIVE guidelines 2.0. PLOS Biology, 2020.

Published 2026 by Dr. Ambuj Shahi. This guide is general information for researchers; follow your institution’s and journal’s requirements.