FLACC Pain Scale

Assesses pain in children (aged between 2 months & 7 years) or other patients who are unable to communicate their symptoms

The FLACC scale assesses the level of pain in pediatric patients who are too young to verbalize their pain. FLACC acronym stands for face, legs, activity, crying, and consolability, the areas observed during the assessment.

The scale was developed by the Department of Anesthesiology, University of Michigan Medical School and Health Systems and can also be used for pain evaluation in intubated patients.

The FLACC scale

The FLACC Scale is a behavioral scale for scoring postoperative pain in children between the ages of two months and seven years or in patients unable to communicate. The scale incorporates five areas: facial expression; leg movement; activity; cry; and consolability, each scored with 0 to 2 points.

There are two sets of instructions for the observers, depending on whether the patients are awake or asleep during evaluation.

For patients who are awake:

■ Observe for at least 2-5 minutes.

■ Observe legs and body uncovered.

■ Reposition patient or observe activity; assess body for tenseness and tone.

■ Initiate consoling interventions if needed.

For patients who are asleep:

■ Observe for at least 5 minutes or longer.

■ Observe body and legs uncovered.

■ If possible reposition the patient.

■ Touch the body and assess for tenseness and tone.

The FLACC scores range from 0 to 10 and are interpreted as follows:

0: Relaxed and comfortable

1 – 3: Mild discomfort

4 – 6: Moderate pain

7 – 10: Severe discomfort/pain

About the original study & validation

The FLACC scale for pain assessment was designed following the 1997 study by Merkel et al. to provide a simple framework for quantifying pain behaviors in pediatric patients unable to verbalize the presence or severity of pain.

The original study consisted in observing in the post anesthesia care unit, a cohort of 89 children aged 2 months to 7 years who had undergone surgical procedures. The study:

■ Measured interrater reliability – which was found to be high;

■ Tested validity by measuring changes in FLACC scores in response to analgesic administration – preliminary evidence of validity was proven through a significant degrease in scores related to administration of analgesics;

■ Compared FLACC scores to other pain rating – validity was also supported by the correlation with scores assigned by the Objective Pain Scale (OPS).

A subsequent study by Voepel-Lewis et al. evaluated the reliability and validity of the Face, Legs, Activity, Cry, Consolability (FLACC) Behavioral Scale in the assessment of pain in critically ill adults and children, unable to self-report. The study cohort consisted in 29 adults and 8 children who were observed simultaneously by three nurses before administration an analgesic or during a painful procedure, and 15 to 30 minutes after the analgesic administration or procedure. Two of the nurses used the FLACC scale whilst the third used the Checklist of Nonverbal Pain Indicators (for adults) and the COMFORT scale (for children).

FLACC scores correlated highly with the other 2 scores, thus supporting criterion validity. Significant decreases in FLACC scores after analgesia (or at rest) supported construct validity. The validation study also observed excellend interrater reliability of the scale, as well as excellent internal consistency (Cronbach alpha was 0.882).


Original reference

Merkel SI, Voepel-Lewis T, Shayevitz JR, Malviya S. The FLACC: a behavioral scale for scoring postoperative pain in young children. Pediatr Nurs. 1997 May-Jun;23(3):293-7.


Voepel-Lewis T, Zanotti J, Dammeyer JA, Merkel S. Reliability and Validity of the Face, Legs, Activity, Cry, Consolability Behavioral Tool in Assessing Acute Pain in Critically Ill Patients. Am J Crit Care. 2010 Jan;19(1):55-61; quiz 62.

Other references

Crellin DJ, Harrison D, Santamaria N, Huque H, Babl FE. The Psychometric Properties of the FLACC Scale Used to Assess Procedural Pain. J Pain. 2018 Aug;19(8):862-872.


We’d love to keep you updated with our latest news and offers 😎