Which of the following statements about insomnia is true?

• A. Insomnia is a rare sleep disorder that affects less than 1% of the population.
• B. Insomnia only occurs in individuals with underlying physical illnesses.
• C. Insomnia is always caused by poor sleep hygiene and never by psychological factors.
• D. Insomnia is characterized by difficulty falling asleep, staying asleep, or waking up too early.

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the definition of insomnia. Insomnia is a common sleep disorder characterized by difficulty falling asleep, staying asleep, or waking up too early and not being able to return to sleep.
2. Step 2: Evaluate the prevalence of insomnia. Recognize that insomnia is not rare; it affects a significant portion of the population, much more than 1%.
3. Step 3: Consider the causes of insomnia. Insomnia can be caused by a variety of factors including psychological issues (like stress or anxiety), physical illnesses, poor sleep hygiene, or a combination of these.
4. Step 4: Analyze the incorrect statements. For example, insomnia is not limited to individuals with physical illnesses, nor is it always caused by poor sleep hygiene alone.
5. Step 5: Conclude that the true statement about insomnia is that it is characterized by difficulty falling asleep, staying asleep, or waking up too early, which aligns with the clinical definition.