Table 1 Examples of data variabilities within the intended use20, 26, 36, 38,39,40, 61, 136,137,138.
Origin | Variabilities |
|---|---|
Patient | • Patient ethnicity • Patient demographics • Disease stage/severity • Rare cases of disease • Comorbidities • Biological differences (genetic, transcriptional, epigenetic, proteomic, and metabolomic) |
Specimen sampling | • Tissue heterogeneity • Size of tissue section • Coverage of diseased/healthy/boundary regions • Tissue damage, e.g., torn, cauterized • Surgical ink present |
Slide processing | • Inter-material and device differences • Preparation differences (fixation, dehydration; freezing; mechanical handling) • Cutting artifacts (torn, folded, deformed, thick or inhomogeneously thick tissue) • Foreign matter/floaters in specimen • Over-/under-staining, inhomogeneous staining • Foreign objects on slide/cover slip (dirt, stain residue, pen markings, fingerprint) • Cracks, air bubbles, scratches • Slide age |
Imaging/image processing | • Inter- and intra-scanner differences • Out-of-focus images, heterogeneous focus • Amount of background in analyzed image region • Magnification/image resolution • Heterogeneous illumination • Grid noise, stitching artifacts • Lossy image compression |
Ground truth annotation | • Inter- and intra-observer differences • Ambiguous cases |
