Effects of Aromatherapy on Sleep Quality and Emotional Status of Hong Kong Nursing Students Facing Final Examination: A Randomized Controlled Trail

Saturday, 26 July 2014: 3:50 PM

Ricky W. K. Yuen, EdD, MN, MSocSc, BN, RN
Margaret Mei Lin Pau, DN, MSc, MN, BN, RN
Wing Yan Yeung, MPH, BNur, RN
School of Nursing, St. Teresa's Hospital, Kowloon, Hong Kong


The purpose of the study is to examine the effects of aromatherapy on the emotional status and sleep quality of the nursing students in Hong Kong facing final examination.


It was a single blind; two groups pretest-post-test randomized controlled trial study. Fifty five students were being blinded and randomly allocated into 2 groups, the intervention group (Group A) and the control group (Group B). All participants in Group A were given 42 drops of pure lavandula augustifolia essential oil inside a 5 ml glass bottle with dropper. Group B would be filled up with 42 drops of pure almond carrier oil in the same type of glass bottle.

Three weeks before the final examination, they were instructed to prepare two gauzes, in which one drop of the oil added to each gauze, and one of them was placed on right side of the pillow and the other on the left side before sleep. The gauze should be placed in a position that they could inhale the aroma. A new piece of gauze with the given oil must be used every night.

Two instruments, Pittsburgh Sleep Quality Index (PSQI) and Depression, Anxiety, Stress Scale (DASS), were adopted in this study to examine the emotional status and sleep quality of nursing students. PSQI is used to examine the sleep quality and it is a 24-item questionnaire assessing the sleep quality and disturbances over a one month time period. The psychometric property of PSQI was examined in other studies and favorable results were documented with reliability coefficient (Cronbach’s alpha) 0.83; sensitivity 89.6% and specificity of 86.5% in distinguishing good and poor sleepers (Buysee et al, 1988). DASS is a 42-item self-report questionnaire grouped into three scales with four-point Likert scale. Scores are calculated by summing up the scores for the relevant items. It yields acceptable reliability with alpha values for the 14-item scales of depression is 0.91; anxiety 0.84 and stress 0.90 (Lovibond & Lovibond, 2004).

Participants were asked to complete two sets of questionnaires, PSQI and DASS, before the commencement of the study as baseline and on the 21stday, ie. the day of final examination. The collected data were analyzed using the Statistical Package for the Social Sciences (SPSS) version 22. Descriptive statistics were used for mean and standard deviation., between baseline and the completion of the programme; repeated measures ANCOVA were used to compare differences between two groups.


Paired-t test was used to compare within outcome of groups and significant improvement in the reduction of stress level (p=.001) and the reduction of anxiety level (p=.044) was found when compared within the intervention group before and after aromatherapy. Apart from paired t-test, ANCOVA was also used to compare the scores and similar results were obtained. Age and gender were identified as covariates and there is a significant difference between the stress (F=(1,56)=12.167. p=.001) and anxiety (F=(1,56)=4.326. p=.042) when compared within the intervention group before and after aromatherapy.

For the between group comparison, the subjective sleep quality, sleep disturbance and overall PSQI total score were found significant improvement (p= <.001, .025 and .001 respectively). The anxiety and stress level of intervention group were also improved significantly (p=<.001 and .001 respectively) when compared with the control group. By using ANCOVA, gender and age as covariates, the significant difference of the subjective sleep quality (F=(1,56)=7.652, p=.001), sleep disturbance (F=(1,56)=3.791, p=.031), overall PSQI total score (F=(1,56)=5.283. p=.001), anxiety (F=(1,56)=9.718, p=.001)and stress level (F=(1,56)=8.645, p=.001) between the intervention and control group still exists.


In conclusion, the findings of the current study suggested that lavender when exposed at night for 21 nights before final examination was beneficial to nursing students and were able to lessen their anxiety level, stress level and overall sleep quality.