Beyond measurement: a deep dive into the commonly used pain scales for postoperative pain assessment

Abstract

This review explores the essential methodologies for effective postoperative pain management, focusing on the need for thorough pain assessment tools, as underscored in various existing guidelines. Herein, the strengths and weaknesses of commonly used pain scales for postoperative pain-the Visual Analog Scale, Numeric Rating Scale, Verbal Rating Scale, and Faces Pain Scale-are evaluated, highlighting the importance of selecting appropriate assessment tools based on factors influencing their effectiveness in surgical contexts. By emphasizing the need to comprehend the minimal clinically important difference (MCID) for these scales in evaluating new analgesic interventions and monitoring pain trajectories over time, this review advocates recognizing the limitations of common pain scales to improve pain assessment strategies, ultimately enhancing postoperative pain management. Finally, five recommendations for pain assessment in research on postoperative pain are provided: first, selecting an appropriate pain scale tailored to the patient group, considering the strengths and weaknesses of each scale; second, simultaneously assessing the intensity of postoperative pain at rest and during movement; third, conducting evaluations at specific time points and monitoring trends over time; fourth, extending the focus beyond the intensity of postoperative pain to include its impact on postoperative functional recovery; and lastly, interpreting the findings while considering the MCID, ensuring that it is clinically significant for the chosen pain scale. These recommendations broaden our understanding of postoperative pain and provide insights that contribute to more effective pain management strategies, thereby enhancing patient care outcomes.

Keywords: Pain; Pain Measurement; Perioperative Care; Postoperative; Postoperative Care; Postoperative Period; Visual Analog Scale.

Fig. 1

Commonly used faces pain scales for postoperative pain management. (A) Faces Pain Scale–Revised (FPS-R). (B) Wong-Baker FACES® Pain Rating Scale. Permission to use the original illustration of the Wong-Baker FACES® Pain Rating Scale has been granted by the Wong-Baker FACES Foundation. Permission to use the original illustration of the FPS-R has been granted by the International Association for the Study of Pain.

Fig. 2

The Defense and Veterans Pain Rating Scale. (A) Pain intensity item. (B) The supplemental questions of the Defense and Veterans Pain Rating Scale. Permission to use this original illustration has been obtained from the Defense & Veterans Center for Integrative Pain Management.

Fig. 3

Recommendations for pain evaluation in studies concerning postoperative pain. MCID: minimal clinically important difference.