All images are acquired on the same examination date. The dataset represents one structural time point, and no internal temporal comparison is possible.

Images are acquired on different dates within a short diagnostic interval — days to several weeks — yet together represent the same structural baseline. RheumaView™ treats such studies as a unified structural baseline rather than as separate longitudinal time points, provided that no clinically meaningful structural change is expected within the interval.

Two or more examinations of the same anatomical region obtained at different time points to assess progression, regression, or stability. Regions must match across time points. Quantitative deltas — measured structural differences between matched time points — are computed for each aligned region.

Cervical, thoracic, and lumbar spine. Does not include sacroiliac joints, pelvis, or hips.

Sacroiliac joints and pelvic bones (ilium, ischium, pubis). Treated as a separate anatomical unit from both the spine and the hips.

Right and left hip joints, evaluated independently from pelvic or spinal datasets.

Spine and pelvic–sacroiliac components analyzed within the same study while preserving their identities as separate anatomical units.

Shoulders, elbows, wrists, and hands.

Hips, knees, ankles, and feet.

Wrist joints together with metacarpophalangeal and interphalangeal joints. A classical unit of assessment in inflammatory arthritis.

Ankle joints together with metatarsophalangeal and interphalangeal joints.

Tibiofemoral and patellofemoral compartments.

Glenohumeral joint and acromioclavicular joint when visible.

One anatomical region only. Example: bilateral knees.

Two or more distinct anatomical regions within the same report. Example: hands and feet.

A full anatomical system, typically an entire limb group. Example: all lower-extremity joints.

Bilateral anatomical structures are included. Examples: both hands, both knees, both hips.

Only one side of a bilateral structure is imaged. Examples: right knee only, left wrist only.

Bilateral anatomy is included incompletely or unevenly — one side missing, underrepresented, or not directly comparable to the other.

One imaging modality only: X-ray, MRI, ultrasound, or CT.

Two or more imaging modalities for the same or related regions. Examples: X-ray plus MRI, MRI plus CT, X-ray plus DEXA.

A single temporal, anatomical, and modality structure with no composite integration. Example: single-date wrist X-ray.

Multiple anatomical regions combined within the same time point. Example: hands plus feet X-ray study.

Different temporal or structural types combined within the same analytical session. Example: hand X-ray from one year and sacroiliac MRI from another. Mixed datasets require explicit handling to avoid false longitudinal comparison across incompatible time points or anatomical scopes.