Sleep Diaries

Original Editor - Romy Hageman
Top Contributors - Romy Hageman

Purpose

An overview of possible items of a sleep diary.

Sleep diaries provide information related to the personal perception of sleep. It is a useful method to access to information about various aspects of sleep (bedtime, sleep duration, sleep onset latency, night awakenings). Parents can also use a sleep diary for the sleep of their children. School / work days and weekends should be analyzed separately.

Sleep diaries have been widely adopted as the favored approach for gathering longitudinal data on self-reported sleep patterns and associated functions in studies focusing on insomnia. They can also help professionals identify targets for cognitive behavioural therapy and can help evaluating an intervention by comparing pre- and post-treatment diaries. It can be a useful screening tool for assessing insomnia.

Technique

• A sleep diary must be filled in at least five nights to provide adequate information about the sleep of adolescents.
• A sleep diary must be filled in for a period of at least seven consecutive days including the weekend for adults. The sleep diary reliability values increase with more nights. An adequate reliability (>0.70) is achieved with seven consecutive days.
• It is preferred to fill out the sleep diary within an hour of waking up.

For an example of a sleep diary watch the video above.

Different sleep diaries

• A sleep diary can comprise a 24-hour timeline, where the individual/parent/child note, for every half-hour interval, whether they/their child was awake or asleep, and the location of their sleep (bedroom, living room, car etc.).
• Saturday and sunday should be included in the sleep diary, because sleep time on weekend differ from sleep time during other days.
• Diaries for children can consist of the following information:
  • Time the child went to bed
  • Time the light were turned of
  • Time the parents think their child woke up
  • Time the child got out of bed
  • Time the child needed to fall asleep
  • Day-time naps
  • Awakenings during the night
  • Difficult behaviours around bed-time
• The most critical parameters for adults are:
  • Time getting into bed
  • Time attempted to fall asleep
  • Sleep onset latency
  • Number of awakenings at night
  • Duration of the awakenings
  • Time of waking up
  • Time of getting up
  • Perceived sleep quality (on a Likert scale)
• Additional parameters could include:
  • Estimated total sleep time
  • Rating of refreshing quality of sleep
  • Napping
  • Alcohol, caffeine, and medicatie use

Advantages

• Minimum supervision required.
• Diaries are valuable for identifying specific events that may have contributed to an unusual night for the child, such as illness or visitors at home. This can help in interpreting information gathered with polysomnography.
• Inexpensive.
• Widely available.
• Easy to use.
• Easy to apply and reliable in field research, clinical evaluations and studies with small and larger numbers of participants.

Disadvantages

• When parents are required to estimate their child's sleep habits, research has indicated that they tend to provide more accurate estimates for sleep schedule variables compared to the time spent awake in bed, including sleep latency and frequency of night awakenings. Furthermore, the consistency of their reports decreased as the duration of monitoring extended: they report earlier bedtimes and later wake-up times when compared to actigraphic measurements, thus overestimating the sleep duration from 30 to 113 minutes per night.
• Adolescents overestimate their sleep duration by one hour and they also underestimate their awakenings during the night.
• Adults seem to overestimate their sleep time by one hour, compared to polysomnography.
• Cognitive factors (function, capacity to estimate time, motivation, ability to maintain the information in long term memory) can play a role in the inaccurate estimation of sleep, especially in children.
• Diaries may suffer from recall bias.
• A lot of people backfill diary data, making it less reliable.
• An actigraphy is often required to validate the data from a sleep diary.
• Filling out a sleep diary takes more time than a questionnaire. It is also time-consuming for the therapist to process the data.

Electronic sleep diary

An electronic sleep diary could have some benefits:

• Promoting self-monitoring of sleep and thus promoting shared decision-making.
• Reminding the patient automatically to complete the sleep diary.
• Controlling timelines and thus avoiding the patient completing more days at the same time.
• Better accuracy, by avoiding illegible responses.
• Less time needed for filling out the diary and also for scoring.

Literature proves that the performance of an electronic sleep diary does not significantly differ from paper sleep diaries. Choosing between the two options may depend on the preference of the therapist and/or the patient.

Psychometric properties

• A sleep diary is useful in detecting improvements from treatment. Sleep diaries can be used in tracking the effects from pre- to posttreatment and for detecting change in the sleep of a patient over time.
• The sleep diary can help discriminating healthy sleepers from the patients with Insomnia Disorder.
• Sleep onset latency (cutoff of 26 min recommended) and Wakefulness after sleep onset (cutoff of 19 minutes recommended) demonstrate adequate sensitivity (73-87%) and specificity (81-86%) in discriminating between healthy sleepers and those with insomnia.