RESUMO
This study aimed to determine validity and reliability of the NIPS [Neonatal Infant Pain Scale] in the neonatal intensive care unit [NICU]. For this study, sixty eight infants were selected using available and purposive sampling method after translating the English version of NIPS to Persian using International Quality of Life Assessment [IQOLA] scale. These children have been filmed before, during and after two interventions of venipuncture and catheter insertion which was required and was ordered by physician. During painful interventions and until three minutes later, heart rate and arterial oxygen saturation of the infants were recorded. Thereafter, five observers [including three nurses, a neonatal specialist and the researcher nurse] scored the infants pain by watching the videos and using the translated version of NIPS. The Interclass correlation coefficient [ICC] was perfect [ICC > 0.9]. The minimum correlation coefficient between inter-rater was 0.868. Validity tests showed a high correlation between NIPS and visual analog scale [r = 0.949; p < 0.001]. According to the confirmed validity and reliability of this scale, use of NIPS in neonatal intensive care units in Iran is possible and can be recommended