Insomnia is a prevalent sleep disorder associated with substantial negative health consequences, including fatigue, irritability, and impaired daytime functioning. Although effective pharmacological and psychological treatments exist, fewer than half of individuals with insomnia seek professional treatment, highlighting the need for accessible and acceptable non-pharmacological interventions. Sleep hygiene education (SHE) has the potential to address this gap due to its simplicity, low cost, and ease of self-administration. However, previous studies have often underestimated the efficacy of SHE by using it as a passive control condition rather than an active, structured intervention. To address this limitation, the proposed pilot study aims to evaluate the feasibility and effectiveness of a theory-based, structured SHE program integrated with behavior change techniques.

Insomnia is a prevalent sleep disorder associated with substantial negative health consequences, including fatigue, irritability, and impaired daytime functioning. Although effective pharmacological (e.g., hypnotics) and psychological treatments (e.g., cognitive behavioral therapy for insomnia, CBT-I) are available, both local and international surveys indicate that fewer than 50% of individuals with insomnia seek treatment. This treatment gap highlights the need to develop effective non-pharmacological interventions that are both accessible and acceptable to individuals with insomnia.

Sleep hygiene education (SHE) represents a potentially suitable intervention to address this unmet need. SHE is an educational approach that encompasses a range of lifestyle and environmental recommendations aimed at optimizing sleep quality and duration, such as maintaining a regular sleep-wake schedule, avoiding substances (e.g., caffeine, nicotine, and alcohol) and daytime napping, limiting stimulating bedtime activities, creating an optimal bedroom environment, and adopting appropriate diet and exercise habits etc. Given its simplicity, low cost, accessibility, and ease of delivery and mastery, SHE holds promise as a non-pharmacological strategy for insomnia management.

Despite these advantages, SHE is not typically recommended as a stand-alone treatment for sleep-vulnerable populations, as it is often perceived to be less effective than CBT-I or mindfulness-based therapies. Notably, the efficacy of SHE may be underestimated. In many prior studies, SHE has been used primarily as a passive control condition to account for nonspecific treatment effects, resulting in its active therapeutic components being largely overlooked.

Advancing SHE beyond a simple advice-giving modality to a structured, theory-informed intervention may enhance its effectiveness by ensuring that its content is not only informative but also practicable and behaviorally achievable. Integrating SHE with evidence-based behavior change techniques may further equip participants with the skills necessary to initiate and sustain meaningful behavioral change. Accordingly, this pilot study aims to examine the feasibility and preliminary effectiveness of a theory-based SHE program previously developed by our team.

Inclusion Criteria:

• Hong Kong residents
• Ethnic Chinese aged 18-65 years with the ability to communicate in Cantonese or Putonghua
• Fulfilled the DSM-5 diagnostic criteria for insomnia disorder according to a validated diagnostic tool, the Brief Insomnia Questionnaire. The criteria included having difficulties falling asleep, staying asleep, or early morning awakening with clinically significant consequences for daily life for at least 3 months
• Scored at least 10 points in the Insomnia Severity Index (ISI)
• Willing to give informed consent

Exclusion Criteria:

• Any current diagnosis fulfilling the DSM-IV criteria of a major depressive disorder, generalized anxiety disorders, post-traumatic stress disorder, panic disorder, substance use disorders, or schizophrenia as screened using the Chinese version of the Structured Clinical Interview for DSM-IV
• Other sleep disorders, including circadian rhythm disorder, narcolepsy, obstructive sleep apnoea (OSA), and restless leg syndrome (RLS)/periodic leg movement disorder (PLMD) as determined based on cut-off scores (≥ 7 on narcolepsy; ≥ 8 on circadian rhythm disorder; ≥ 15 on OSA; ≥ 7 on RLS/PLMD) using SLEEP-50. If in doubt, subjects will be referred to our team psychiatrist (KF Chung) for further assessment
• Any current medical conditions or side-effects of medication that are contributing significantly to the subject's insomnia
• Taking medications or currently participating in other psychotherapies for insomnia or other psychiatric disorders
• Impaired cognitive functioning (<22 points in HK-MoCA) or with difficulty in giving consent or understanding instructions
• Pregnant
• Shift work