Virtual Reality Applications in Chronic Pain Management: Systematic Review and Meta-analysis

Abstract

Background: Virtual reality (VR) is a computer technology that immerses a user in a completely different reality. The application of VR in acute pain settings is well established. However, in chronic pain, the applications and outcome parameters influenced by VR are less clear.

Objective: This review aimed to systematically identify all outcome parameters that are reported in relation to VR in patients with chronic pain.

Methods: A total of 4 electronic databases (PubMed, Scopus, Web of Science, and Embase) were searched for relevant studies. Multilevel random-effect meta-analyses were performed, whereby the standardized mean difference was chosen as the effect size to denote the difference between measurements before and after a VR intervention.

Results: The initial database search identified 1430 studies, of which 41 (2.87%) were eventually included in the systematic review. Evidence has been found for the effects of VR on pain, functioning, mobility, functional capacity, psychological outcomes, quality of life, neuropsychological outcomes, and physical sensations. The overall effect size (a total of 194 effect sizes from 25 studies) based on a three level meta-analysis was estimated at 1.22 (95% CI 0.55-1.89; z=3.56; P<.001), in favor of improvements after a VR intervention. When categorizing effect sizes, the overall effect sizes were reported as follows: 1.60 (95% CI 0.83-2.36; z=4.09; P<.001) for the effect of VR on pain (n=31), 1.40 (95% CI 0.13-2.67; z=2.17; P=.03) for functioning (n=60), 0.49 (95% CI -0.71 to 1.68; z=0.80; P=.42) for mobility (n=24), and 0.34 (95% CI -1.52 to 2.20; z=0.36; P=.72) for functional capacity (n=21).

Conclusions: This systematic review revealed a broad range of outcome variables influenced by an intervention of VR technology, with statistically significant pain relief and improvements in functioning. These findings indicate that VR not only has applications in acute pain management but also in chronic pain settings, whereby VR might be able to become a promising first-line intervention as complementary therapy for patients with chronic pain.

Trial registration: PROSPERO International Prospective Register of Systematic Reviews CRD42021227016; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=227016.

Keywords: chronic pain; clinical outcomes; immersive technologies; mobile phone; multilevel meta-analysis; systematic review; virtual reality.

Figure 1

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) flowchart.

Figure 2

Summary forest plot for the effect of virtual reality on all outcome measurements in patients with chronic pain. Each line presents the results of 1 study (potentially including multiple effect sizes). The meta-analytic mean, with the corresponding 95% CI, is presented with a black dot and black line. This black 95% CI represents the total study precision. The additional CI in gray is based on the sampling variance of individual observed effect sizes of the study to obtain a visual contribution of the study sample size on the total study precision. The thickness of the gray CI is proportional to the number of effect sizes within studies. The number of effect sizes per study is presented as "J" on the right side of the figure [45,49,52,55-60,62-65,69-73,75-79,82,83].

Figure 3

Caterpillar plots with all effect sizes (A) and study effect sizes (B). The overall effect size is presented in red.

Figure 4

A funnel plot of all effect sizes (A) and a study funnel plot (B).

Figure 5

Reported effect sizes from the studies exploring (A) pain, (B) functioning, (C) mobility, and (D) functional capacity. Significant effects were found for pain and functioning outcome variables. Effect sizes from individual studies are presented in black, and the overall effect size is shown in red.