Table 3.

Smile task quality checklist.

Rule/issue			Penalty
Idle duration
	Idle >5 s before or after the task	1 point
	Idle ≥5 s between smiles	2 points
Background contrast and blurriness
	Dark/low-contrast background or blurry video, but face remains clearly visible	1 point
	Face visibility impaired (unclear face)	2 points
Multiple people in frame
	Photos/pictures of other people visible in background	1 point
	Another person’s face appears in the recording frame	2 points
Eyeglasses
	No glare or negligible glare	OK
	Glare present, eyes remain partially visible	1 point
	Glare severely obstructs visibility of either eye	2 points
Smile count
	Exactly 3 smiles	OK
	4 or 5 smiles	1 point
	<3 or >5 smiles	2 points
Expression ambiguity
	Smile resembles laughter or executed too quickly	1 point
Body movement
	Multiple head/body movements during smiles, but head always in the frame	1 point
	Head leaves the frame during the task	2 points
Distance from camera
	Head-and-shoulders (headshot) framing	OK
	Waist visible in frame	1 point
	Lower body (eg, knees) visible; too far from camera	2 points
Noncompliance (any of the following)
	No smile-task recording; recorded on phone/tablet (instructed to use computer/laptop); face not fully visible; unstable/shaky camera; not forward-facing (bad angle); participant speaks during task	2 points