Today, psychophysiological insomnia is the most common persistent insomnia. Lavender essential oil is frequently used in the literature as an aromatherapy method to improve sleep quality. Studies have found that lavender improves sleep quality. They also emphasized that more studies are needed in this area. When the relevant literature is reviewed, no studies examining the effects of lavender oil on patients with psychophysiological insomnia were found. In this context, the aim of the study was to evaluate the effect of lavender on sleep quality and insomnia severity in patients with psychophysiological insomnia.

Today, psychophysiological insomnia is the most common persistent insomnia. The patient's inability to sleep occurs as a result of repetitive negative thoughts such as the thought that he will have difficulty sleeping before going to bed and/or past experiences involving the bedroom or the night. More effort to sleep causes more wakefulness and more difficulty falling asleep.

Numerous studies have shown that insomnia seriously affects health and quality of life and can cause various problems including memory problems, depression, irritability, cardiovascular and cerebrovascular diseases, etc. Therefore, looking for effective ways to improve sleep quality is important for individual and social health. Today, drug therapy, psychotherapy, physiotherapy and cognitive-behavioral therapy are widely used treatments for insomnia. Recently, more and more studies have found that aromatherapy is one of the non-drug treatments to improve sleep quality. Lavender essential oil appears in the literature as an aromatherapy method frequently used to improve sleep quality.

Studies have found that lavender improves sleep quality. They also emphasized that more studies are needed in this area. When the relevant literature was examined, no studies were found examining the effects of lavender oil on patients with psychophysiological insomnia. In this context, the aim of the study was to evaluate the effect of lavender on sleep quality and insomnia severity in patients with psychophysiological insomnia.

Inclusion Criteria:

• Being 18 years of age or older,
• Being over 65 years old
• Being diagnosed with psychophysiological insomnia,
• Knowing Turkish at a level that will allow you to read and understand the survey questions,
• Accepting to participate in the study

Exclusion Criteria:

• Having a serious physical or cognitive disability that would prevent him/her from answering the survey,
• Being under the age of 18,
• Not accepting to participate in the study,
• Being allergic to lavender,
• Having a chronic additional disease related to the respiratory system,
• Having a psychiatric or neurological additional disease,
• Using medication(s) that may affect sleep,
• Experiencing a physical activity limitation that causes bedriddenness,
• Having or contracting a disease that will affect the ability to smell.

participants and outcome assessors will not be informed about group assignments and will be blinded.