# ConductScience Elevated Plus Maze Anxiety Index Calculator: method and validation record

This record fixes the calculation behind the free Elevated Plus Maze Anxiety Index Calculator at https://conductscience.com/tools/elevated-plus-maze-anxiety-index, and the worked examples that check it.

## What the tool computes

From each animal's arm times and arm entries in an elevated plus maze session:

- % open-arm time and % open-arm entries;
- the Anxiety Index, 1 − [(open-arm time / session time) + (open-arm entries / total arm entries)] / 2;
- total arm entries and % center time;
- a flag when the zone times do not add up to the session time;
- group means, SDs and SEMs of each measure.

## Files

| File | Contents |
| --- | --- |
| `METHODS.md` | Formulas, conventions, references, and changes from the page before this record |
| `cases.json`, `cases.csv` | The worked examples: inputs, expected outputs and where each expected answer comes from |
| `validation-report.json` | The engine's output for every case, pass or fail, and the SHA-256 of each engine file |
| `engine/` | The calculation source files the report fingerprints (when included) |
| `data_dictionary.csv` | Columns of `cases.csv` |
| `CITATION.cff`, `LICENSE`, `MANIFEST.json` | Citation metadata, licence, and byte count and SHA-256 of every file |

## How to cite

ConductScience. ConductScience Elevated Plus Maze Anxiety Index Calculator [software]. 2026. https://doi.org/10.55157/csd.tool.epm.2026.001

In a methods section: "Percent open-arm time, percent open-arm entries and the Anxiety Index, 1 − [(open-arm time / total time) + (open-arm entries / total entries)] / 2 (Hoffman et al., 2015), were calculated with the ConductScience Elevated Plus Maze Anxiety Index Calculator (https://doi.org/10.55157/csd.tool.epm.2026.001)."