fvewa/LookBack

NBME Lung AI Anchoring — Dataset

Gaze recordings, radiologist annotations, AI predictions, and imaging data from a within-subject three-condition study of AI-induced attentional anchoring in 3D CT lung nodule reading (16 radiologists × 60 LIDC-IDRI cases × 3 conditions).

Repository contents

Collections/                                   # Per-session gaze and annotation data
├── R{1-16}_Set{1,2}_R1/                       # First run: Exp2 (Concurrent CAD)
│   ├── Trial1.csv                             # Gaze time series (6 columns, no Phase)
│   └── Trial1.json                            # Reader bounding-box annotations for Exp2
│
└── R{1-16}_Set{1,2}_R2/                       # Second run: Exp3 (Gaze-guided second look)
    ├── Trial1.csv                             # Gaze time series (7 columns, with Phase)
    ├── Trial1_firstread.json                  # Annotations after independent first read (also used as Exp1)
    └── Trial1_secondlook.json                 # Annotations added after gaze-guided second-look prompt

images_bbox/
└── sets/
    ├── set1/                                  # 30 cases
    │   ├── ai_nodules.json                    # AI (RetinaNet) predicted bounding boxes per case
    │   ├── gt_nodules.json                    # Ground-truth nodule bounding boxes per case
    │   ├── vol/                               # CT volumes (.nii.gz), one per case
    │   ├── gt/                                # GT nodule masks
    │   ├── lung_mask/                         # Lung field masks
    │   └── pred/                              # Per-case AI prediction files
    └── set2/                                  # 30 cases, same structure

Reader anonymization

Original participant names have been replaced with anonymous IDs R1–R16. R12 participated in Set 1 only; all other readers completed both sets.

Session naming and mapping to experimental conditions

R{reader}_Set{1,2}_R{1,2} — e.g. R3_Set1_R2 is reader R3, Set 1, Run 2.

• Set1 = 30 CT cases; Set2 = 30 CT cases
• R1 (first run) is always Exp2 (Concurrent CAD): the reader read each case with AI-suggested bounding boxes shown throughout.
• R2 (second run) is Exp3 (Gaze-guided second look), which is a two-phase session recorded in a single file set. The first-read phase of R2 is additionally used as Exp1 (Independent reading) in all analyses that require a no-AI baseline from the same reader on the same cases.

Phase extraction:

Analysis target	Gaze (Trial1.csv)	Annotations
Exp1 (Independent)	R2 session, rows where Phase == "first_read"	Trial1_firstread.json from R2 session
Exp2 (Concurrent CAD)	R1 session (entire CSV; no Phase column)	Trial1.json from R1 session
Exp3 (Gaze-guided second look)	R2 session, both Phase == "first_read" and Phase == "second_look" rows combined	Trial1_firstread.json + Trial1_secondlook.json from R2 session (combined; de-duplicate overlapping boxes)

Notes:

• R1 session CSVs have 6 columns (no Phase) because Exp2 is a single uninterrupted read.
• R2 session CSVs have 7 columns, the last being Phase ∈ {"first_read", "second_look"}.
• Every R2 session contains both Trial1_firstread.json and Trial1_secondlook.json. The secondlook file lists annotations added after the gaze-guided second-look prompt; some may overlap firstread boxes and should be de-duplicated when forming Exp3 annotations.
• R12 did not have an Exp2 run for Set 2 (no R12_Set2_R1 session). R12_Set2_R2 is present but was excluded from all analyses in the companion paper due to data-quality issues (see the paper's analysis-populations table).

File formats

Trial1.csv (gaze recording)

Columns:

• Time: HH:MM:SS wall-clock timestamp (local to recording session)
• Gaze_Location_X/Y: screen coordinates in pixels (display 2560×1080)
• Slice Number: CT axial slice index (0-based) at the moment of fixation
• Duration: fixation duration (sampling-rate dependent; typically ~1 at 50–60 Hz)
• File Name: relative path to the viewed CT volume (set{N}/vol/LIDC-IDRI-XXXX_vol.nii.gz)
• Phase (R2 sessions only): first_read or second_look

Trial1.json / Trial1_firstread.json / Trial1_secondlook.json (annotations)

Dict mapping LIDC-IDRI-XXXX → list of bounding boxes. Each bounding box: [z1, y1, x1, z2, y2, x2] where z indexes axial slices and y, x are in pixel coordinates relative to the CT volume.

ai_nodules.json / gt_nodules.json

Dict mapping LIDC-IDRI-XXXX → list of bounding boxes in the same format.

Volumes

NIfTI .nii.gz CT volumes derived from LIDC-IDRI. Original DICOM data is publicly available via The Cancer Imaging Archive (TCIA): https://www.cancerimagingarchive.net/collection/lidc-idri/

Citation and license

Please cite the associated paper when using this dataset. The 60 CT cases are derived from LIDC-IDRI, which is distributed under its own license; please also cite LIDC-IDRI (Armato et al., Medical Physics 2011).

Dataset license: CC-BY 4.0 (see LICENSE), applied to the gaze recordings, reader annotations, AI predictions, and derived masks. LIDC-IDRI source imagery retains its original terms.