The recent evidence suggested substantial anxiolytic efficacy of lavender. The aim of this study was to examine the efficacy of lavender for anxiety, depression, and physiological parameters and to elucidate the differential effects of lavender on anxiety and depression by study characteristics. A systematic review and meta-analysis was performed following the PRISMA guidelines. We searched PubMed, Embase, Cochrane Library, Web of Science, and Cumulative Index of Nursing and Allied Health Literature databases for randomized controlled trials investigating the efficacy of lavender on anxiety, depression, or physiological parameters in humans. We assessed the risk of bias within studies with the revised Cochrane risk of bias tool for randomized trials. We used random effect model to estimate the average effect and computed bias-corrected standardized mean difference as effect size metric, Hedges' ĝ for all outcomes. Lavender was superior to placebo or no treatment in reducing anxiety (Hedges' ĝ = -0.72, 95% confidence interval [CI] -0.90 to -0.55, p value <.001), depression (Hedges' ĝ = -0.43, 95% CI, -0.59 to -0.27, p value <.001), and systolic blood pressure (Hedges' ĝ = -0.23, 95% CI, -0.41to -0.05, p value = .01). The moderator analysis by meta-regression indicated that route of administration accounted 6.5% (p value = .187) for the heterogeneity in anxiolytic effects, sessions of treatment accounted 13.2% (p value = .055), and participants' health state accounted 8.9% (p value = .131) for the variance in anxiolytic effects. Lavender aromatherapy showed substantial effect in reducing anxiety and depression, and sessions of administration increased the anxiolytic effects. The effects on physiological parameters showed small with inconsistent significances and randomized controlled trials on the effect of lavender on depression were scarce. Future trials on depression and physiological parameters are recommended, and increasing the sessions of administration is recommended.

Although lavender is purported to possess anxiolytic and sedative properties and is often recommended for relieving anxiety, the efficacy of lavender has not been well established. Thus, this review aimed to evaluate the anxiolytic effects of lavender aromatherapy. Ten data bases were searched for studies published between 2000 and 2018. Randomized controlled trials investigating the anxiolytic effects of lavender aromatherapy with any type of application for persons with or without clinical anxiety were included. The outcome variables included self-rated anxiety, vital signs, and salivary cortisol and chromogranin A (CgA) levels. In the meta-analysis, standardized mean difference and 95% confidence interval were calculated as effect measures by applying the random effect model and inverse variance method. Twenty-two trials met our inclusion criteria. Lavender aromatherapy was found to have favorable effects in relieving anxiety (Hedges' ĝ = -0.65; 95% CI, -0.84 to -0.46) and decreasing systolic blood pressure (ĝ = -0.22; 95% CI, -0.43 to -0.02), heart rate (ĝ = -0.53; 95% CI, -0.74 to -0.32), and salivary cortisol (ĝ = -1.29; 95% CI, -2.23 to -0.35) and CgA (ĝ = -2.29; 95% CI, -3.24 to -1.34) levels. However, the meta-analysis did not reveal any significant effects of lavender on diastolic blood pressure (effect size: -0.17; 95% CI, -0.37-0.04). Aromatherapy using lavender oil might have favorable effects on anxiety and its physiological manifestations. Future studies are recommended with an emphasis on methodological quality. In nursing practice, it is suggested that lavender aromatherapy be included in programs intended to manage anxiety in patients across diverse healthcare settings.

Evidence on factors influencing the variations of music effect on anxiety and pain in surgical patients is unclear. We aimed to elucidate the effects of music intervention on anxiety and pain by study characteristics. We conducted a search on the PubMed, CINAHL, Embase, Cochrane, and Web of Science databases from March 7 to April 21, 2022, for randomized controlled trials (RCTs) for the effect of music intervention on anxiety, pain, and physiological responses in surgical patients. We included studies published within the last 10 years. We assessed the risk of bias in study using the Cochrane risk of bias tool for randomized trials and performed meta-analyses using random-effects model for all outcomes. We used change-from-baseline scores as summary statistics and computed bias-corrected standardized mean difference (Hedges'g) for anxiety and pain outcomes and mean differences (MD) for blood pressure and heart rate. Of the 454 records retrieved, 30 RCTs involving 2280 participants were found to be eligible. Music intervention was found to be superior to standard care in reducing anxiety (Hedges'g = -1.48, 95% confidence interval: -1.97 to -0.98), pain (Hedges'g = -0.67, -1.11 to -0.23), systolic blood pressure (MD = -4.62, -7.38 to -1.86), and heart rate (MD = -3.37, -6.65 to -0.10) in surgical patients. The impact of music on anxiety and pain relief varied significantly depending on the duration of the intervention. The largest effect was observed in interventions lasting between 30 to 60 minutes, with a decrease in anxiety and pain. Music intervention is an effective way to reduce anxiety, pain, and physiological response in surgical patients. Future reviews examining the influence of different types of surgery on the effects of music would add to the body of knowledge in this field. This study has been registered on PROSPERO under the number CRD42022340203, with a registration date of July 4, 2022.

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Chae YR, et al. Korean J Health Promot. 2019 Dec;19(4):229-236. https://doi.org/10.15384/kjhp.2019.19.4.229

Dear reviewers, You conducted a significant review and meta-analysis on the effect of aromatherapy for children. I read the manuscript closely, and I suggest some comments on your work based on the PRISMA 2020 statement and checklist. I wrote my re...