Related Experiment Video
Updated: May 13, 2025
Assessment and Evaluation of the High Risk Neonate: The NICU Network Neurobehavioral Scale
Published on: August 25, 2014
Clinical rating scales for assessing pain in newborn infants
Kenneth Färnqvist1, Emma Olsson2,3, Andrew Garratt4
1Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
Insights
Current pain rating scales for newborns have very low-certainty evidence, raising concerns about their validity and reliability. Further development and testing of these neonatal pain assessment tools are crucial for infant safety.
Area of Science:
- Neonatal care
- Pain management
- Clinical assessment
Background:
- Neonatal intensive care units (NICUs) admit 6-9% of newborns, often requiring painful procedures.
- Accurate pain assessment is vital for safe and effective pain management in neonates.
- Existing pain rating scales have limitations in validity, leading to potential under- or over-treatment of pain.
Purpose of the Study:
- To systematically review and describe the development, content, and measurement properties of clinical pain rating scales for newborn infants.
- To identify gaps in the evidence regarding the appropriateness of these scales for different pain types and infant conditions.
Main Methods:
- Systematic literature search of CENTRAL, PubMed, Embase, and CINAHL up to July 2023.
- Inclusion of all study designs involving the development or testing of neonatal pain rating scales.
- Evaluation of rating scales using Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) and a modified GRADE approach.
Main Results:
- Included 79 studies with 7197 infants, utilizing 27 clinical rating scales across 26 countries.
- All rating scales demonstrated very low-certainty evidence based on COSMIN criteria.
- Concerns identified regarding the validity, reliability, and applicability of current scales in diverse neonatal settings.
Conclusions:
- Clinical staff must exercise vigilance when using existing neonatal pain rating scales.
- Prioritization of further development in rating scale content and structural validity testing is essential.
- Collaborative efforts between clinicians and methodology experts are needed to enhance the validity and reliability of neonatal pain assessment tools.
Background:
Six to nine per cent of all newborn infants require admission to a neonatal intensive care unit (NICU) due to either illness or prematurity. During their stay, these infants are often subjected to many painful procedures that can cause negative long-term consequences. To reduce the negative effects of pain exposure and ensure optimal and safe pain treatment, accurate assessment of pain is necessary. To achieve this, clinicians are dependent on the use of reliable, objective, and standardised clinical rating scales of pain, henceforth referred to as 'rating scales'. Numerous rating scales have been published; however, discrepancies in validity limit their overall applicability in clinical practice and research. Such limitations may lead to an over- or underestimation of pain, resulting in unnecessary sedation or inadequately treated pain, potentially jeopardising infant safety through treatment side effects, including withdrawal symptoms or prolonged discomfort. To date, the majority of rating scales have been developed to assess procedural pain, whilst fewer scales for prolonged pain are available. Premature infants further complicate matters, as they often have a reduced ability to display robust pain behaviour due to their immaturity. Research has also shown that the use of rating scales in clinical practice is suboptimal, due to both inadequate and infrequent implementation alongside inappropriate choice of scale for the specific pain, population, or setting under evaluation. Despite numerous studies investigating the burden of pain in newborn infants, little work has been done to summarise the current evidence on the appropriateness of rating scales for specific types of pain or infant conditions. This has likely been limited by the subjectivity of pain assessment and further complication of assessing such a non-verbal and immature patient population. The immense burden of neonatal pain worldwide has also led to the development of numerous rating scales in various languages, further hindering evidence summation.
Objectives:
To systematically review the literature to compile and describe the development, content, and measurement properties of clinical rating scales for the assessment of pain in newborn infants.
Search Methods:
An Information Specialist systematically searched CENTRAL, PubMed, Embase, and CINAHL. The latest update search is current to July 2023.
Selection Criteria:
We included all study designs that involved the development or testing of a rating scale for assessing pain in newborn infants. We included preterm (born before week 37) and term (born at week 37 or beyond) infants undergoing pain assessment for any medical indication. We also included studies that included healthcare professionals.
Data Collection And Analysis:
We evaluated clinical rating scales assessing pain in newborn infants using the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) methodology evaluating content validity, structural validity, internal consistency, reliability, measurement error, hypothesis testing, and cross-cultural validation. We used a modified GRADE approach to assess risk of bias, inconsistency, imprecision, and indirectness.
Main Results:
We included 79 studies involving a total of 7197 infants, 326 nurses, and 12 physicians. Twenty-seven clinical rating scales were used in 26 countries, with 14 studies evaluating preterm infants, 11 on term infants, 46 on both preterm and term infants, four solely on medical staff, and four on preterm and/or term infants plus medical staff. Following the COSMIN checklist, we found all rating scales to be of very low-certainty evidence, raising concerns regarding their validity, reliability, and applicability in this vulnerable population across diverse clinical settings.
Authors' Conclusions:
Clinical staff should be vigilant when applying the currently available neonatal rating scales. Further development of rating scale content and testing for structural validity are necessary and should be prioritised. Together, they determine the content and structure of rating scales, underpin further testing, including reliability, and their prioritisation will make the greatest contribution to the evidence base for rating scales to assess neonatal pain. Collaborative efforts between clinicians and methodology experts will prevent methodological pitfalls and contribute to improving the validity and reliability of pain-rating scales in neonatology.
