MRI Quality Control
Each series in each scan undergoes quality control (QC) at the Mayo ADIR Lab. Two levels of quality control are performed:
![quality passed](https://adni.loni.usc.edu/wp-content/themes/adni_2023/images/iconify-check-circle.png)
![next](https://adni.loni.usc.edu/wp-content/themes/adni_2023/images/iconify-arrow-right-on.png)
Trained analysts manually inspect images to ensure series-specific quality, and assign a numerical grade each scan: 1-3 is acceptable and 4 is failure (unusable).
Factors that are taken into account in assigning this grade include:
![Presence and severity of artifacts](https://adni.loni.usc.edu/wp-content/themes/adni_2023/images/iconify-presence-artifacts.png)
Presence and severity of artifacts
(e.g., participant motion)
![anatomical coverage](https://adni.loni.usc.edu/wp-content/themes/adni_2023/images/iconify-anatomical-coverage.png)
Anatomical coverage:
ensuring that the entire head was imaged
![completeness](https://adni.loni.usc.edu/wp-content/themes/adni_2023/images/iconify-completeness.png)
Completeness:
all slices were acquired and transmitted
![overall quality](https://adni.loni.usc.edu/wp-content/themes/adni_2023/images/iconify-overall-quality.png)
Overall image quality
QC information is available for each series on LONI, and users can employ scan-level QC information as filters in preparing image collections.