FLACC scale
The FLACC scale (Face, Legs, Activity, Cry, Consolability) is a behavioral observational tool designed to quantify pain intensity in non-verbal patients, particularly infants and young children aged 2 months to 7 years undergoing postoperative recovery, by scoring observable behaviors across five categories on a 0-2 scale each, resulting in a total score ranging from 0 (no pain) to 10 (severe pain).[1] Developed in 1997 by nurse researchers Sandra Merkel and Terri Voepel-Lewis at the University of Michigan's Section of Pediatric Anesthesia, the scale provides a structured framework for healthcare providers to assess pain when self-reporting is not possible, such as in preverbal children or those with cognitive impairments.[2] The scale's components include facial expression (e.g., relaxed versus grimacing), leg movement (e.g., relaxed versus kicking), body activity (e.g., lying quietly versus squirming), cry (e.g., content versus high-pitched), and consolability (e.g., easily consoled versus difficult to console), with observations typically conducted over 1-5 minutes to ensure reliability.[1] Initial validation involved 89 children in a post-anesthesia care unit, demonstrating high interrater reliability (weighted kappa >0.8) and construct validity through correlation with analgesic administration and other pain measures.[1] Subsequent studies have expanded its application beyond postoperative settings to procedural pain, chronic conditions, and intubated or cognitively impaired patients. A revised version (r-FLACC), published in 2006, improves reliability for children with cognitive impairment by allowing customization of behavioral descriptors in each category.[3] Widely adopted in pediatric nursing and anesthesia protocols, the FLACC scale remains a cornerstone of pain management due to its simplicity, objectivity, and evidence-based reliability across diverse clinical contexts.[1]Background
Definition and Purpose
The FLACC scale, an acronym for Face, Legs, Activity, Cry, and Consolability, is a validated behavioral pain assessment tool developed to evaluate acute pain in young children who cannot reliably self-report their discomfort.[1] It targets infants and children from 2 months to 7 years of age, focusing on observable nonverbal cues to determine pain intensity in clinical environments.[4] This approach is particularly useful for preverbal patients, where traditional verbal reporting is not feasible.[5] The primary purpose of the FLACC scale is to provide a structured, quantifiable method for healthcare providers to measure pain levels through behavioral indicators, enabling timely and appropriate interventions in postoperative recovery or acute care scenarios.[1] By assigning scores to specific observable behaviors, it supports objective decision-making for analgesia administration and pain relief strategies, ultimately improving patient outcomes in pediatric settings.[4] The scale's simplicity and reliability have made it a standard tool in nursing and medical practice for this population.[6] Unlike self-report instruments such as the Visual Analog Scale (VAS) or the Wong-Baker FACES Pain Rating Scale, which rely on the child's ability to verbally describe or visually indicate their pain level, the FLACC scale depends entirely on the observer's trained interpretation of the child's physical and vocal responses.[5] This observer-based methodology addresses limitations in self-reporting for nonverbal children, prioritizing behavioral evidence over subjective input.[7]Target Population
The FLACC scale is primarily intended for infants and young children aged 2 months to 7 years who cannot reliably self-report pain due to their developmental stage, cognitive impairments, or conditions such as sedation that limit verbal communication.[1] This age range encompasses preverbal children in whom behavioral observations serve as the main indicators of pain intensity, making the scale a practical tool for clinicians assessing acute discomfort without relying on subjective reports.[4] It finds particular application in postoperative recovery environments, where it was originally validated to quantify pain behaviors following surgical procedures in this demographic.[1] Beyond surgery, the scale is widely employed in emergency departments for evaluating procedural or injury-related pain in young children, as well as in pediatric intensive care units (PICUs) for ongoing monitoring of critically ill patients exhibiting nonverbal pain cues.[8][9] For children with cognitive or developmental delays, a revised version of the FLACC (r-FLACC) incorporates individualized pain indicators to enhance accuracy, extending its utility to this subgroup while maintaining the core behavioral focus.[3] The scale's nonverbal, observational design also proves advantageous for non-English-speaking children or those from diverse linguistic backgrounds, as it bypasses language barriers inherent in self-report tools.[4]Development and History
Original Creation
The FLACC scale was developed in 1997 by Sandra I. Merkel, a clinical nurse specialist, along with Terri Voepel-Lewis, Jay R. Shayevitz, and Shobha Malviya, all affiliated with C.S. Mott Children's Hospital at the University of Michigan.[1] This collaborative effort aimed to create an accessible observational tool for evaluating pain in young children. The primary rationale for the scale's creation was to bridge the existing gap in reliable, straightforward pain assessment methods for preverbal children, who often cannot articulate their discomfort.[1] Building upon earlier behavioral pain scales, the developers sought to simplify the process, enabling its use by healthcare providers without specialized training in pediatric pain management.[1] This focus on usability addressed the limitations of more complex tools that required extensive expertise, ensuring broader applicability in clinical settings like postoperative care.[1] The foundational framework of the five categories emerged from initial observations of pain behaviors in children.[1] Initial validation involved observations of 89 children aged 2 months to 7 years in the post-anesthesia care unit, where behaviors were systematically observed to establish the tool's core components.[1]Key Studies and Publications
The landmark publication introducing the FLACC scale appeared in 1997, titled "The FLACC: A Behavioral Scale for Scoring Postoperative Pain in Young Children," authored by Sandra I. Merkel, Terri Voepel-Lewis, Jay R. Shayevitz, and Shobha Malviya in the journal Pediatric Nursing. This study detailed the initial validation of the scale in 89 postoperative children aged 2 months to 7 years, demonstrating high interrater reliability with coefficients ranging from 0.74 to 0.94 across observations. Preliminary validity was established through significant reductions in FLACC scores following analgesia administration, highlighting the scale's sensitivity to pain changes in controlled postoperative settings.[1] Subsequent research expanded the scale's applicability beyond typical postoperative scenarios. In 2002, Voepel-Lewis et al. evaluated the FLACC in children with cognitive impairments, confirming its reliability (interrater correlation r=0.80) and validity through correlations with other pain measures, thus broadening its use for non-verbal populations unable to self-report pain. A further refinement, the revised FLACC (r-FLACC), was introduced in 2006 by Malviya et al., incorporating parent- or caregiver-identified behaviors to enhance reliability (interrater ICC=0.99) and validity in cognitively impaired children, making it more adaptable for diverse clinical contexts.[10][3] Research in the 2010s focused on procedural and non-postoperative pain, reinforcing the scale's versatility. For instance, studies validated its use in venipuncture and immunization settings, showing consistent interrater reliability (ICC >0.80) and responsiveness to procedural stimuli. A 2015 systematic review by Crellin et al. in Pain analyzed 25 studies and confirmed the FLACC's strong reliability and construct validity across various pain types, though noting the need for more evidence in procedural contexts.[11] Additionally, a 2018 study by Crellin et al. in The Journal of Pain examined the psychometric properties of the FLACC for procedural pain using video recordings of 100 children aged 6 to 42 months undergoing peripheral intravenous insertion or venipuncture, finding high interrater reliability (ICC=0.92) and good sensitivity (94.9%) with a mean difference of 4.2 points between painful and nonpainful phases.[12] More recent research, including a 2023 systematic review by Li et al. summarizing 15 studies on psychometric properties in diverse pediatric settings and a 2025 Spanish adaptation of the r-FLACC by Alcoba et al. validating its use in cognitively impaired children (interrater ICC >0.95), continues to support the scale's robustness.[13][14]Scale Components
Face
The Face category in the FLACC scale evaluates observable facial expressions as a primary indicator of pain in young, preverbal children, who often cannot articulate their discomfort verbally.[1] This component focuses on subtle to overt changes in the child's countenance during pain assessment, serving as an initial cue for clinicians to detect distress in postoperative or procedural settings.[15] Scoring for the Face category ranges from 0 to 2, based on the frequency and intensity of pain-related expressions, as defined in the original development of the scale.[1]| Score | Description |
|---|---|
| 0 | No particular expression or smile |
| 1 | Occasional grimace or frown; withdrawn, disinterested |
| 2 | Frequent to constant quivering chin, clenched jaw (or frequent to constant grimace) |
Legs
The Legs category within the FLACC scale evaluates lower extremity positioning and movements as behavioral indicators of pain in young children, particularly those unable to verbalize discomfort. This component focuses on observable changes in leg tone and activity, which can reflect the child's response to painful stimuli. Developed as part of a behavioral observation tool for postoperative pain assessment, the Legs category helps clinicians quantify subtle motor responses in the lower body that may accompany acute pain episodes.[1] Scoring for the Legs category is assigned based on direct observation of the child's leg position and any dynamic movements, with each level corresponding to increasing intensity of discomfort signals. A score of 0 indicates normal position or relaxed legs, suggesting no evident pain-related tension. A score of 1 denotes uneasy, restless, or tense legs, often with subtle shifts in position. A score of 2 reflects more pronounced distress, such as kicking or legs drawn up toward the torso. These descriptors are derived from validated behavioral criteria in the original scale.[1]| Score | Description |
|---|---|
| 0 | Normal position or relaxed |
| 1 | Uneasy, restless, tense |
| 2 | Kicking or legs drawn up |
Activity
The Activity category in the FLACC scale evaluates a child's overall body posture, tone, and mobility as indicators of pain, focusing on patterns of movement or stillness that reflect discomfort during postoperative or procedural assessments.[1] Observers assess the child's torso and limbs for signs of agitation or rigidity, which may intensify as pain levels rise, providing insight into the physical manifestation of distress without relying on verbal reports.[1] Scoring for Activity is based on observable motor behaviors, rated on a 0-2 scale during a brief observation period of at least 1-5 minutes, depending on the child's state of wakefulness.[1]| Score | Description |
|---|---|
| 0 | Lying quietly, normal position, moves easily |
| 1 | Squirming, shifting back and forth, tense |
| 2 | Arched, rigid, or jerking |
Cry
The Cry component of the FLACC scale assesses vocalizations as a key behavioral indicator of pain in young children, capturing how auditory expressions vary with pain intensity. This category is essential for evaluating distress in nonverbal or preverbal patients, where crying serves as a direct, observable sign of discomfort during postoperative recovery or procedural pain.[1] The scoring for the Cry category ranges from 0 to 2, based on the frequency, duration, and intensity of vocal sounds:| Score | Description |
|---|---|
| 0 | No cry (awake or asleep) |
| 1 | Moans or whimpers; occasional complaint |
| 2 | Crying steadily, screams or sobs; frequent complaints |
Consolability
The Consolability category in the FLACC scale evaluates a child's responsiveness to soothing interventions, providing insight into the emotional and behavioral impact of pain. This component assesses whether the child remains distressed despite attempts at comfort, distinguishing it from initial vocalizations by focusing on post-intervention behavior. Developed as part of the original FLACC framework for nonverbal children aged 2 months to 7 years, it helps quantify how pain disrupts the child's ability to be calmed, with scores reflecting varying levels of emotional regulation.[1] Scoring for Consolability ranges from 0 to 2, based on observed responses during assessment:| Score | Description |
|---|---|
| 0 | Content, relaxed. |
| 1 | Reassured by occasional touching, hugging, or being talked to; distractible. |
| 2 | Difficult to console or comfort. |