Domain: Healthcare — Basic Immunology
Target concept: Skin Allergic Reaction (Pollen)

Video generation prompt: A pollen-allergic patient placed both arms horizontally on a table, with the palmar surfaces upward. A pollen allergen diluted to 100 μg/mL with normal saline was applied as one drop on the palmar skin of the left forearm, and the skin was pricked gently with a sterile lancet to a depth that did not cause bleeding. Normal saline was applied as one drop on the palmar skin of the right forearm, following the same procedure. The image was focused on both arms, and continuous photographs were taken for thirty minutes.

Evaluation guide:
(i) Target concept: Immediate-type (Type I) hypersensitivity reaction mediated by allergen-specific IgE bound to cutaneous mast cells.
Minimum mechanism: Intact epidermal barrier permitting allergen access to dermal mast cells; functional IgE-FcεRI signaling; intact histamine release and vascular response pathways; absence of systemic anaphylaxis triggers.
(ii)Storyline (the clip may depict a compressed time-lapse of the prompt's real ~30-minute observation window): [Start] Arms settle into horizontal position, palms up; one pollen-allergen drop is visible on the left forearm and one saline drop is visible on the right forearm. [Shortly after start] Lancet touches the left forearm drop site, leaving a puncture mark, then touches the right forearm drop site, leaving a matching puncture mark. [Over the remaining simulated ~30 minutes] The left forearm gradually develops a discrete, raised, erythematous wheal confined to the prick site, becoming clearly visible only after several simulated minutes have passed, not immediately at the prick, while the right (saline) forearm stays visually unchanged apart from its puncture mark. Perspective: fixed frontal mid-shot, centered on both forearms, no zoom/pan, full visibility of palmar surfaces and drop locations throughout.

Manual:
Experimental Procedure
1. Patient places both arms horizontally on table, palmar surfaces upward.
2. One drop of pollen allergen (100 μg/mL in saline) applied to left forearm palmar skin; one drop of normal saline applied to right forearm palmar skin.
3. Sterile lancet pricks skin at each drop site—no bleeding.
4. Fixed frontal camera captures both forearms continuously for thirty minutes.
Observation of Experimental Phenomena
Left forearm gradually develops a localized, raised, erythematous, circular wheal over the course of the 30-minute observation, becoming clearly established within roughly 15-20 minutes (consistent with standard skin-prick-test reading times); right forearm shows only the initial transient puncture mark throughout—no wheal, erythema, or swelling develops.
Summary of Experimental Principles
Pollen-specific IgE on mast cells triggers degranulation upon allergen exposure + skin prick, causing histamine release → vasodilation + increased permeability → wheal-and-flare, a response that takes several minutes to develop and is typically read at 15-20 minutes. Saline control confirms specificity.

Prompt Grounding rubric:
level_1: No forearms are visible on a table at all; or the arms are not laid flat with palms facing up; or there's no visible left-vs-right distinction between the two forearms; or no drop of liquid is applied to either forearm; or nothing resembling a lancet or pricking tool ever appears; or the shot never shows both forearms together in one static frontal view.
level_2: Both arms rest palms-up on the table, but only one forearm is actually shown in the frame; or a liquid drop appears on one or both forearms but it's unclear which drop is the pollen-allergen one and which is the saline one; or the lancet is implied to touch the skin but no actual puncture action is shown; or the camera view doesn't keep both forearms together side by side in one fixed shot.
level_3: Both forearms rest horizontally on the table with palms facing up and are both fully visible in the same shot; one liquid drop sits on the left forearm and a separate liquid drop sits on the right forearm; a lancet-like tool visibly touches the skin at both drop sites; the left and right forearms are laid out next to each other within one steady frontal view.
level_4: Both forearms stay in the frame as described for a 3-point video, and in addition the left drop and right drop are unambiguous about which forearm they belong to (their positions never get confused or swapped); the lancet touches the left site and the right site as two separate, distinguishable actions rather than one blurred motion; nothing (a sleeve, a hand, an instrument) blocks the view of either drop or puncture site; both forearms hold their position without shifting throughout the entire recorded observation, from the initial drop placement through the final wheal check.
level_5: Everything described for a 4-point video is present, and in addition the left forearm clearly shows its single drop followed by a distinct lancet touch, and the right forearm clearly shows its own single drop followed by a distinct lancet touch, with the left and right actions kept visually distinguishable (whether sequential or simultaneous); the camera never repositions, crops in, or changes viewpoint at any point; both forearms stay in frame at the same scale and orientation from the very first shot to the very last.

Scientific and Causal Correctness rubric:
level_1: No skin change appears on either forearm at any point; or a wheal-like reaction shows up on the saline (right) forearm instead of the allergen (left) one; or a reaction is visible before the lancet ever touches the skin; or the reaction looks like bleeding, a blister, or broken skin rather than a raised red wheal; or both forearms end up looking the same, with no visible contrast between them.
level_2: A reaction does appear on only one forearm, but its timing doesn't make sense (e.g., it's visible before that arm's lancet prick); or a very similar-looking reaction shows up on both forearms with the same onset and shape; or the change shown isn't a skin wheal at all (e.g., a glow, mist, or color wash extending past the skin); or the saline-side forearm develops swelling or redness that's hard to tell apart from the allergen side's reaction.
level_3: A raised, red, roughly circular wheal appears only on the left (allergen) forearm, and only after its lancet prick; the right (saline) forearm shows nothing beyond a brief puncture mark, with no swelling or redness developing there; the left forearm's reaction stays confined to the skin surface, without bleeding, weeping, or broken skin; the two forearms end up looking clearly different from each other.
level_4: The left forearm's wheal only starts appearing after its lancet prick, never before; the right forearm still shows nothing more than its puncture mark, with no redness, swelling, or raised skin developing there over time; the right side's puncture mark doesn't grow or change on its own as the clip goes on; there's no scratching, wiping, or other hand contact disturbing either site.
level_5: The left forearm's wheal builds up gradually and stays confined to roughly where the drop and lancet prick were, without spreading noticeably beyond that immediate area; the right forearm's puncture mark stays a small, fading mark with no lasting discoloration or swelling; the left wheal's emergence is visibly gradual rather than instantaneous, consistent with it taking real time to develop rather than appearing the moment the lancet touches the skin; nothing about the pattern looks like a slower second-phase reaction or a whole-body/systemic sign; the story stays limited to the expected localized, immediate-type response.

Spatiotemporal Consistency rubric:
level_1: Either forearm vanishes from the shot and reappears somewhere else; the tabletop's look or edges change abruptly between moments; the lighting suddenly swings between very bright and very dark; a forearm appears to break into disconnected pieces; the background flickers in and out inconsistently.
level_2: One forearm briefly bends and then appears fully straight moments later with no motion shown in between; either forearm gets blocked from view for a stretch of the clip and then reappears; shadows on the skin point in a different direction than they did a moment earlier; light on the skin flickers unnaturally; the table's edge shifts sideways noticeably between moments.
level_3: Both forearms stay visible the whole time, keeping the same side-by-side layout and alignment on the table; the tabletop looks the same and stays put throughout; light and shadow on the arms point the same way from start to finish; nothing appears or disappears without some visible motion getting it there; neither forearm's shape looks stretched, bent unnaturally, or distorted.
level_4: The lancet's approach to the skin follows a short, smooth path rather than suddenly appearing already touching the skin; each liquid drop's arrival on the forearm is shown as continuous motion from wherever it comes from, not as an instant appearance; the framing never zooms, pans, or shifts perspective partway through; neither arm shows any unexplained shaking, twitching, or drifting from its resting position.
level_5: Motion throughout the clip looks smooth rather than jerky or stuttering; the lancet touching the skin doesn't produce any unrealistic bounce or recoil; each liquid drop keeps a consistent shape and highlight from the moment it's placed onward; the two forearms don't shift position relative to each other as the camera or scene changes; no frame or moment appears to repeat itself.