Table 1: The difference between the original NIPS and English-back translation of its Vietnamese version

English-back translation of Vietnamese NIPS		The original NIPS (Lawrence et al., 1993)
Facial Expression		Facial Expression
0 - Relaxed muscles1 - Grimace	Restful face, neutral expressionTight facial muscles, furrowed brow, chin, jaw	0 - Relaxed muscles1 - Grimace	Restful face, neutral expressionTight facial muscles, furrowed brow, chin, jaw
Cry		Cry
0 - Not crying1 - Whimper2 - Vigorous cry	Quiet, not cryingMild moaning, intermittentLoud scream, shrill, continuous (Note: Silent cry may be scored if the infant is intubated, when there is evidences by obvious mouth, facial movements)	0 - No cry1 - Whimper2 - Vigorous cry	Quiet, not cryingMild moaning, intermittentLoud scream, shrill, continuous(Note: Silent cry may be scored if baby is intubated, as evidenced by obvious mouth, facial movement)
Breathing Patterns		Breathing Patterns
0 - Relaxed1 - Change in breathing	Usual breathing patternIndrawing, irregular, faster than usual, gagging, breath holding	0 - Relaxed1 - Change in breathing	Usual breathing pattern for this babyIndrawing, irregular, faster than usual, gagging, breath holding
Arms		Arms
0 - Relaxed /restrained1 - Flexed /extended	No muscular rigidity, occasional random movements of armsTense, straight arms, rigid and/or rapid extension/flexion	0 - Relaxed /restrained1 - Flexed /extended	No muscular rigidity, occasional random movements of armsTense, straight arms, rigid and/or rapid extension/flexion
Legs		Legs
0 - Relaxed /restrained1 - Flexed /extended	No muscular rigidity, occasional random movements of legsTense, straight legs, rigid and/or rapid extension/flexion	0 - Relaxed /restrained1 - Flexed /extended	No muscular rigidity, occasional random leg movementTense, straight legs, rigid and/or rapid extension/flexion
State of Arousal		State of Arousal
0 - Sleeping /awake1 - Fussy	Quiet, peaceful, sleeping or alert and stabilizedAlert, restless, and thrashing	0 - Sleeping /awake1 - Fussy	Quiet, peaceful, sleeping or alert and settledAlert, restless, and thrashing

^* Total score from 0 to 7
0-2: no pain; 3-4: moderate pain; >4: severe pain