Domain: Healthcare — Clinical Laboratory Science
Target concept: Hemoglobin Test in Urine (Aminophenazone Method)

Video generation prompt: Collect 1 mL of urine from a patient with excessive urinary hemoglobin, add 0.3 mL of hydrogen peroxide aniline reagent and 0.2 mL of chromogen reagent to the tube, mix thoroughly, and observe.

Evaluation guide:
(i) Target concept: Enzymatic peroxidase-like activity of hemoglobin enabling chromogen oxidation to colored product.
Minimum mechanism: Urine must contain functional hemoglobin (not free heme or myoglobin); both reagents must be present and react only upon mixing; color formation requires hemoglobin-catalyzed H2O2 decomposition and subsequent chromogen oxidation; no color without hemoglobin or without both reagents.
(ii)Storyline: [Start] Urine in tube (pale yellow, transparent) → [Addition 1] Hydrogen peroxide aniline reagent dispensed → no color change → [Addition 2] Chromogen reagent dispensed → no color change → [Mixing] Tube rotated/vortexed → [Color onset] Pink-red hue emerges uniformly throughout liquid → [Stabilization] Color intensifies slightly then remains stable; all events viewed from fixed frontal angle showing tube center, pipette tips, and liquid column; no occlusion of tube contents during mixing or observation.

Manual:
Experimental Procedure
1. Collect 1 mL urine into a clean test tube.
2. Add 0.3 mL hydrogen peroxide aniline reagent using a calibrated pipette.
3. Add 0.2 mL chromogen reagent using a calibrated pipette.
4. Cap tube and mix thoroughly by gentle rotation or vortexing.
Observation of Experimental Phenomena
A pink-to-red color develops in the mixture only after both reagents are added and mixing is complete.
Summary of Experimental Principles
Hemoglobin in urine catalyzes oxidation of chromogen by hydrogen peroxide, producing a pink-red quinoneimine dye — positive result indicates intravascular hemolysis.

Prompt Grounding rubric:
level_1: No urine-filled tube, no hydrogen peroxide aniline reagent, and no chromogen reagent ever appear, whether together or separately; no pipetting or mixing action is shown at all.
level_2: Exactly one of the three required materials (the urine-filled tube, the hydrogen peroxide aniline reagent, or the chromogen reagent) appears at some point, but the other two are never shown; the pipetting and mixing steps are missing or are shown acting on the wrong container.
level_3: Exactly two of the three required materials (urine-filled tube, hydrogen peroxide aniline reagent, chromogen reagent) appear together in the same shot but the third is never shown, or all three appear yet the addition order does not match 1 mL urine, then 0.3 mL aniline reagent, then 0.2 mL chromogen reagent.
level_4: All three materials appear together and are added to the tube in the correct order and approximate volumes (1 mL urine, 0.3 mL aniline reagent, 0.2 mL chromogen reagent) using pipettes that are visually distinguishable from one another by size, labeling, or graduation markings consistent with the differing volumes; the tube stays stationary throughout the pipetting and mixing steps; the urine is visibly pale yellow rather than clear like water or a dye; no extraneous objects or steps appear beyond the three additions and the mixing action; but a reagent label is illegible or a pipetting action is only implied rather than clearly shown.
level_5: All conditions for score 4 are satisfied, and additionally the labels on both the hydrogen peroxide aniline reagent and the chromogen reagent are clearly legible and match their names, every pipetting action is clearly and unambiguously shown rather than merely implied, mixing is performed with a clear rotational or vortex motion rather than shaking or tapping, the pipette tips touch the liquid surface without splashing, and the final mixed volume in the tube visually matches the combined roughly 1.5 mL of urine and reagents.

Scientific and Causal Correctness rubric:
level_1: The liquid in the tube stays the same pale yellow throughout, or the two reagents look identical in color to the urine, with nothing in the video linking the addition and mixing steps to any change in color.
level_2: A color change happens, but it is the wrong color (blue, purple, or green instead of pink-red), or the color appears before mixing is complete, or it appears after only one reagent has been added, or the urine itself starts out red as if it already contained visible blood.
level_3: A pink-to-red color appears only after both reagents have been added and mixing is finished; before that point the urine is pale yellow and both reagents look colorless or only faintly tinted.
level_4: The pink-red color deepens gradually while mixing continues rather than flashing on instantly, the hue stays a clean pink-red rather than drifting toward orange, brown, or magenta, and the color looks the same near the top of the liquid column as near the bottom rather than settling darker at the bottom or paler at the top.
level_5: The pink-red color matches evenly across the whole liquid column with no darker ring at the tube wall or meniscus, holds steady for the rest of the observation without fading or darkening further, and the specific shade matches the pink-red expected for a positive hemoglobin test rather than a violet or brick-red tone.

Spatiotemporal Consistency rubric:
level_1: The tube suddenly appears in a different spot with no motion in between, a reagent bottle vanishes and reappears without being set down, the mixing action starts before the liquids have finished being added, the lighting suddenly jumps to a different look, or the tube appears cracked or bent with no cause.
level_2: There are more than two abrupt cuts between the pipetting steps, the pipette tip disappears mid-transfer and reappears elsewhere, the liquid level in the tube resets between additions instead of rising step by step, the mixing motion stops and restarts without a smooth transition, or the room lighting shifts inconsistently between shots.
level_3: There is one brief cut between pipetting steps where the hand or tube position does not carry over smoothly, or the lighting flickers briefly during mixing, or the tube wobbles once with nothing supporting it; but the tube never breaks, disappears, or changes shape.
level_4: The pipetting, addition, and mixing steps play out from a single fixed camera angle with the hand, tube, and pipette staying in a believable spatial relationship throughout, the liquid surface stays undisturbed as each pipette approaches, and the scene's brightness never jumps.
level_5: Motion throughout the clip is fully continuous with no strobing or blur that breaks up the action, the liquid meniscus rises and settles smoothly during each addition without sloshing back and forth, the tube stays upright and in the same orientation the whole time, and the hand's motion follows a natural, unhurried path with no sudden repositioning of the camera.