adolescent sleep

Adolescent sleep worsens with age. Specifically, longitudinal research demonstrates that sleep duration shortens during the transition from high school to college.{{Cite journal|last1=Park|first1=Heejung|last2=Chiang|first2=Jessica J.|last3=Irwin|first3=Michael R.|last4=Bower|first4=Julienne E.|last5=McCreath|first5=Heather|last6=Fuligni|first6=Andrew J.|date=2019-08-01|title=Developmental trends in sleep during adolescents' transition to young adulthood|journal=Sleep Medicine|volume=60|pages=202–210|doi=10.1016/j.sleep.2019.04.007|pmid=31186213|pmc=6650269|issn=1389-9457}} Additionally, sleep efficiency (the amount of time spent asleep when in bed) decreased during this transition. Day-to-day variability in sleep duration increased during this transition, suggesting that adolescent sleep duration becomes less stable with time. A variety of social, physical, biological, and psychological factors change during adolescence which contributes to declines in sleep.{{Cite journal|last1=Crowley|first1=Stephanie J.|last2=Wolfson|first2=Amy R.|last3=Tarokh|first3=Leila|last4=Carskadon|first4=Mary A.|date=2018-08-01|title=An update on adolescent sleep: New evidence informing the perfect storm model|journal=Journal of Adolescence|volume=67|pages=55–65|doi=10.1016/j.adolescence.2018.06.001|pmid=29908393|pmc=6054480|issn=0140-1971}} In particular, puberty has been explored as a contributor to changes in adolescent sleep. Luteinizing hormone (LH) is secreted during sleep at the onset of pubertal maturation, pointing to an important relationship between sleep and pubertal development.{{Cite journal|last1=Boyar|first1=Robert|last2=Finkelstein|first2=Jordan|last3=Roffwarg|first3=Howard|last4=Kapen|first4=Sheldon|last5=Weitzman|first5=Elliot|last6=Hellman|first6=Leon|date=1972-09-21|title=Synchronization of Augmented Luteinizing Hormone Secretion with Sleep during Puberty|journal=New England Journal of Medicine|volume=287|issue=12|pages=582–586|doi=10.1056/NEJM197209212871203|issn=0028-4793|pmid=4341276}}

The National Sleep Foundation recommends that teenagers (14–17 years) obtain 8 to 10 hours of sleep.{{cite journal |last1=Hirshkowitz |first1=Max |last2=Whiton |first2=Kaitlyn |last3=Albert |first3=Steven M. |last4=Alessi |first4=Cathy |last5=Bruni |first5=Oliviero |last6=DonCarlos |first6=Lydia |last7=Hazen |first7=Nancy |last8=Herman |first8=John |last9=Adams Hillard |first9=Paula J. |last10=Katz |first10=Eliot S. |last11=Kheirandish-Gozal |first11=Leila |last12=Neubauer |first12=David N. |last13=O’Donnell |first13=Anne E. |last14=Ohayon |first14=Maurice |last15=Peever |first15=John |last16=Rawding |first16=Robert |last17=Sachdeva |first17=Ramesh C. |last18=Setters |first18=Belinda |last19=Vitiello |first19=Michael V. |last20=Ware |first20=J. Catesby |title=National Sleep Foundation's updated sleep duration recommendations: final report |journal=Sleep Health |date=December 2015 |volume=1 |issue=4 |pages=233–243 |doi=10.1016/j.sleh.2015.10.004 |pmid=29073398 }} Their recommendation further stipulates that less than 7 hours and more than 11 hours of sleep may be harmful. Additionally, it is recommended that young adults (18–25 years) obtain 7 to 9 hours of sleep and avoid sleep less than 6 hours and more than 11 hours.

Adolescent sleep researchers have conducted studies to provide stronger empirical evidence for sleep recommendations. Fuligni and colleagues (2019) examined a sample of American adolescents and found that younger adolescents, especially those with elevated levels of internalizing symptoms, need more sleep in order to experience optimum levels of positive mood the next day.{{cite journal |last1=Fuligni |first1=Andrew J. |last2=Bai |first2=Sunhye |last3=Krull |first3=Jennifer L. |last4=Gonzales |first4=Nancy A. |title=Individual Differences in Optimum Sleep for Daily Mood During Adolescence |journal=Journal of Clinical Child & Adolescent Psychology |date=18 August 2017 |volume=48 |issue=3 |pages=469–479 |doi=10.1080/15374416.2017.1357126 |pmid=28820607 |pmc=5817027 }} Additionally, another study examining Mexican-American youth found that roughly 7.5 hours of sleep was predictive of high GPA but 8.75 hours of sleep was predictive of lower internalizing symptoms.{{cite journal |last1=Fuligni |first1=Andrew J. |last2=Arruda |first2=Erin H. |last3=Krull |first3=Jennifer L. |last4=Gonzales |first4=Nancy A. |title=Adolescent Sleep Duration, Variability, and Peak Levels of Achievement and Mental Health |journal=Child Development |date=March 2018 |volume=89 |issue=2 |pages=e18–e28 |doi=10.1111/cdev.12729 |pmid=28129442 |pmc=5529284 }} This finding suggests that optimal sleep duration differs depending on the outcome.

More research is needed to understand individual differences in sleep duration during adolescence.{{Cite journal|last1=Fuligni|first1=Andrew J.|last2=Bai|first2=Sunhye|last3=Krull|first3=Jennifer L.|last4=Gonzales|first4=Nancy A.|date=2017-08-18|title=Individual Differences in Optimum Sleep for Daily Mood During Adolescence|journal=Journal of Clinical Child & Adolescent Psychology|volume=48|issue=3|pages=469–479|doi=10.1080/15374416.2017.1357126|pmid=28820607|pmc=5817027|issn=1537-4416}}

Sleep duration has been declining since the early 90s according to research.{{cite journal |last1=Keyes |first1=Katherine M. |last2=Maslowsky |first2=Julie |last3=Hamilton |first3=Ava |last4=Schulenberg |first4=John |title=The Great Sleep Recession: Changes in Sleep Duration Among US Adolescents, 1991–2012 |journal=Pediatrics |date=1 March 2015 |volume=135 |issue=3 |pages=460–468 |doi=10.1542/peds.2014-2707 |pmid=25687142 |pmc=4338325 }} Evidence also suggests that teen females, ethnic minorities, and those of low socioeconomic status experience the lowest durations. Puberty is thought to contribute to poor sleep during adolescence as teens undergo physical and social maturation.{{cite journal |last1=Carskadon |first1=Mary A. |last2=Vieira |first2=Cecilia |last3=Acebo |first3=Christine |title=Association between Puberty and Delayed Phase Preference |journal=Sleep |date=1 May 1993 |volume=16 |issue=3 |pages=258–262 |doi=10.1093/sleep/16.3.258 |pmid=8506460 |doi-access=free }} For adolescents, this inclination is demonstrated by their tendency to stay up later and sleep longer, particularly on holidays or weekends.{{Cite journal |last1=Ming |first1=Xue |last2=Koransky |first2=Rebecca |last3=Kang |first3=Victor |last4=Buchman |first4=Sarah |last5=Sarris |first5=Christina E. |last6=Wagner |first6=George C. |date=2011 |title=Sleep Insufficiency, Sleep Health Problems and Performance in High School Students |journal=Clinical Medicine Insights: Circulatory, Respiratory and Pulmonary Medicine |language=en |volume=5 |pages=71–79 |doi=10.4137/CCRPM.S7955 |issn=1179-5484 |pmc=3212860 |pmid=22084618}} A burgeoning area of adolescent sleep research is focused on understanding the contribution of technology-use to poor teen sleep.{{cite journal |last1=Bowers |first1=Jennifer M. |last2=Moyer |first2=Anne |title=Adolescent sleep and technology-use rules: results from the California Health Interview Survey |journal=Sleep Health |volume=6 |issue=1 |pages=19–22 |doi=10.1016/j.sleh.2019.08.011 |pmid=31732441 |year=2020 |pmc=7346706 |doi-access=free }} Importantly, research shows that declines in adolescent sleep duration are characteristic of adolescents around the world.{{Cite journal|last1=Gradisar|first1=Michael|last2=Gardner|first2=Greg|last3=Dohnt|first3=Hayley|date=2011-02-01|title=Recent worldwide sleep patterns and problems during adolescence: A review and meta-analysis of age, region, and sleep|journal=Sleep Medicine|volume=12|issue=2|pages=110–118|doi=10.1016/j.sleep.2010.11.008|pmid=21257344|issn=1389-9457}} The consequences of poor extend far beyond mere fatigue, leading to various physical, cognitive, and mental health issues.{{Cite journal |last1=Seton |first1=Christopher |last2=Fitzgerald |first2=Dominic A. |date=2021 |title=Chronic sleep deprivation in teenagers: Practical ways to help |url=https://doi.org/10.1016/j.prrv.2021.05.001 |journal=Paediatric Respiratory Reviews |volume=40 |pages=73–79 |doi=10.1016/j.prrv.2021.05.001 |pmid=34144910 |issn=1526-0542|url-access=subscription }}

Poor sleep duration has been found to be related to altered brain development during adolescence. Telzer and colleagues (2015) found that teens with greater day-to-day variability in their sleep duration had lower white matter integrity one year later.{{cite journal |last1=Telzer |first1=Eva H. |last2=Goldenberg |first2=Diane |last3=Fuligni |first3=Andrew J. |last4=Lieberman |first4=Matthew D. |last5=Gálvan |first5=Adriana |title=Sleep variability in adolescence is associated with altered brain development |journal=Developmental Cognitive Neuroscience |date=1 August 2015 |volume=14 |pages=16–22 |doi=10.1016/j.dcn.2015.05.007 |pmid=26093368 |pmc=4536158 }} This result remained when controlling for sleep duration, which suggests that sleep variability may be more consequential for teen brain development than simply duration. Another study found that sleep duration was strongly associated with gray matter volume of the bilateral hippocampus among a sample of healthy children and adolescents.{{cite journal |last1=Taki |first1=Yasuyuki |last2=Hashizume |first2=Hiroshi |last3=Thyreau |first3=Benjamin |last4=Sassa |first4=Yuko |last5=Takeuchi |first5=Hikaru |last6=Wu |first6=Kai |last7=Kotozaki |first7=Yuka |last8=Nouchi |first8=Rui |last9=Asano |first9=Michiko |last10=Asano |first10=Kohei |last11=Fukuda |first11=Hiroshi |last12=Kawashima |first12=Ryuta |title=Sleep duration during weekdays affects hippocampal gray matter volume in healthy children |journal=NeuroImage |date=1 March 2012 |volume=60 |issue=1 |pages=471–475 |doi=10.1016/j.neuroimage.2011.11.072 |pmid=22197742 |s2cid=17421225 }}

Poor sleep duration and increased risk-taking has been a well-established association in the adolescent sleep literature. A recent meta-analysis reported that poor sleep duration results in a 1.43 times greater odds of engaging in risky behaviors.{{cite journal |last1=Short |first1=Michelle A. |last2=Weber |first2=Nathan |title=Sleep duration and risk-taking in adolescents: A systematic review and meta-analysis |journal=Sleep Medicine Reviews |date=1 October 2018 |volume=41 |pages=185–196 |doi=10.1016/j.smrv.2018.03.006 |pmid=29934128 |hdl=2328/38429 |s2cid=49379148 |hdl-access=free }} The direction of the relationship between risk-taking and sleep duration is still unknown, thus causal claims cannot be made.{{Cite journal|last1=Calamaro|first1=Christina J.|last2=Mason|first2=Thornton B. A.|last3=Ratcliffe|first3=Sarah J.|date=2009-06-01|title=Adolescents Living the 24/7 Lifestyle: Effects of Caffeine and Technology on Sleep Duration and Daytime Functioning|url=https://pediatrics.aappublications.org/content/123/6/e1005|journal=Pediatrics|language=en|volume=123|issue=6|pages=e1005–e1010|doi=10.1542/peds.2008-3641|issn=0031-4005|pmid=19482732|s2cid=30851634 |url-access=subscription}}

A plethora of research shows that low sleep duration is linked with poor mood.{{cite journal |last1=Owens |first1=Judith A. |last2=Dearth-Wesley |first2=Tracy |last3=Lewin |first3=Daniel |last4=Gioia |first4=Gerard |last5=Whitaker |first5=Robert C. |title=Self-Regulation and Sleep Duration, Sleepiness, and Chronotype in Adolescents |journal=Pediatrics |date=1 December 2016 |volume=138 |issue=6 |pages=e20161406 |doi=10.1542/peds.2016-1406 |pmid=27940688 |doi-access=free }} Furthermore, youth who report low sleep duration also demonstrate difficulties with emotion regulation.{{cite journal |last1=Baum |first1=Katherine T. |last2=Desai |first2=Anjali |last3=Field |first3=Julie |last4=Miller |first4=Lauren E. |last5=Rausch |first5=Joseph |last6=Beebe |first6=Dean W. |title=Sleep restriction worsens mood and emotion regulation in adolescents |journal=Journal of Child Psychology and Psychiatry |date=February 2014 |volume=55 |issue=2 |pages=180–190 |doi=10.1111/jcpp.12125 |pmid=24889207 |pmc=4047523 }} This is of particular concern because adolescents experience fluctuations in mood as a result of pubertal maturation, however, poor sleep duration worsens mood and regulation abilities rendering these adolescents vulnerable.

Empirical evidence suggests that sleep quality is poor during adolescence.{{Cite journal|last1=Dahl|first1=Ronald E|last2=Lewin|first2=Daniel S|date=2002-12-01|title=Pathways to adolescent health sleep regulation and behavior|journal=Journal of Adolescent Health|series=Health Futures of Youth II: Pathways to Adolescent Health|volume=31|issue=6, Supplement|pages=175–184|doi=10.1016/S1054-139X(02)00506-2|pmid=12470913|issn=1054-139X}} Poor sleep quality during adolescence has been linked with a variety of negative behaviors and outcomes. For instance, poor sleep quality has been shown to be positive associated with anxiety and depressive symptoms among teens. A study published in 2016 found that sleep quality significantly mediated the relationship between age and depressive symptoms, suggesting that the rise in depressive symptoms during adolescence is partly explained by poor sleep quality.{{Cite journal|last1=Raniti|first1=Monika B.|last2=Allen|first2=Nicholas B.|last3=Schwartz|first3=Orli|last4=Waloszek|first4=Joanna M.|last5=Byrne|first5=Michelle L.|last6=Woods|first6=Michael J.|last7=Bei|first7=Bei|last8=Nicholas|first8=Christian L.|last9=Trinder|first9=John|date=2017-05-04|title=Sleep Duration and Sleep Quality: Associations With Depressive Symptoms Across Adolescence|journal=Behavioral Sleep Medicine|volume=15|issue=3|pages=198–215|doi=10.1080/15402002.2015.1120198|issn=1540-2002|pmid=26744783|s2cid=46808892 }} A long line of research has also demonstrated that poor sleep quality is associated with increased risk-taking behaviors among teens.{{Cite journal|last1=O'Brien|first1=Erin M.|last2=Mindell|first2=Jodi A.|date=2005-08-01|title=Sleep and Risk-Taking Behavior in Adolescents|journal=Behavioral Sleep Medicine|volume=3|issue=3|pages=113–133|doi=10.1207/s15402010bsm0303_1|issn=1540-2002|pmid=15984914|s2cid=12919106 }} Neuroscience research (fMRI) has found that poor sleep quality is associated with greater risk-taking on a behavioral task.{{Cite journal|last1=Telzer|first1=Eva H.|last2=Fuligni|first2=Andrew J.|last3=Lieberman|first3=Matthew D.|last4=Galván|first4=Adriana|date=2013-05-01|title=The effects of poor quality sleep on brain function and risk taking in adolescence|journal=NeuroImage|volume=71|pages=275–283|doi=10.1016/j.neuroimage.2013.01.025|pmid=23376698|pmc=3865864|issn=1053-8119}} This risky behavior was further associated with decreased activity in cognitive control regions of the brain and increased activity in reward regions of the brain. Moreover, poor sleep quality has been found to be linked with dampened intra-network connectivity of regions in the Default Mode Network, a brain network that undergoes development during adolescence.{{Cite journal|last1=Tashjian|first1=Sarah M.|last2=Goldenberg|first2=Diane|last3=Monti|first3=Martin M.|last4=Galván|first4=Adriana|date=2018-03-01|title=Sleep quality and adolescent default mode network connectivity|journal=Social Cognitive and Affective Neuroscience|language=en|volume=13|issue=3|pages=290–299|doi=10.1093/scan/nsy009|pmid=29432569|pmc=5836271|issn=1749-5016|doi-access=free}}

There has been an increased interest in understanding the relationship between sleep and technology use among adolescents. In the era of social media, there is a growing concern for blue-light emitted by technology may be interfering with adolescents' ability to obtain restful and sufficient sleep.{{Cite news|url=https://www.theatlantic.com/magazine/archive/2017/09/has-the-smartphone-destroyed-a-generation/534198/|title=Have Smartphones Destroyed a Generation?|last=Twenge|first=Story by Jean M.|date=September 2017|work=The Atlantic|access-date=2019-12-09|issn=1072-7825}} Use of technologies (i.e. television, cell phone, computer/laptop) is associated with prolonged sleep duration (the amount of time it takes to fall asleep) and shorter sleep duration among teenagers.{{Cite journal|last1=Arora|first1=Teresa|last2=Broglia|first2=Emma|last3=Thomas|first3=G. Neil|last4=Taheri|first4=Shahrad|date=2014-02-01|title=Associations between specific technologies and adolescent sleep quantity, sleep quality, and parasomnias|journal=Sleep Medicine|volume=15|issue=2|pages=240–247|doi=10.1016/j.sleep.2013.08.799|pmid=24394730|issn=1389-9457}} Television use was associated with the poorest sleep duration. Adolescent technology-use has also been linked with excessive daytime sleepiness and caffeine consumption,{{Cite journal|last1=Calamaro|first1=Christina J.|last2=Mason|first2=Thornton B. A.|last3=Ratcliffe|first3=Sarah J.|date=2009-06-01|title=Adolescents Living the 24/7 Lifestyle: Effects of Caffeine and Technology on Sleep Duration and Daytime Functioning|url=https://pediatrics.aappublications.org/content/123/6/e1005|journal=Pediatrics|language=en|volume=123|issue=6|pages=e1005–e1010|doi=10.1542/peds.2008-3641|issn=0031-4005|pmid=19482732|s2cid=30851634 |url-access=subscription}} suggesting that technology-use may interfere with sleep and may lead to increased caffeine consumption. Longitudinal data demonstrates that time spent using technology is predictive of short sleep duration, however short sleep duration was also predictive of time spent using technology.{{Cite journal|last1=Mazzer|first1=K.|last2=Bauducco|first2=S.|last3=Linton|first3=S. J.|last4=Boersma|first4=K.|date=2018-07-01|title=Longitudinal associations between time spent using technology and sleep duration among adolescents|journal=Journal of Adolescence|volume=66|pages=112–119|doi=10.1016/j.adolescence.2018.05.004|pmid=29842997|s2cid=44118163 |issn=0140-1971}} More longitudinal research with larger sample sizes is needed to clarify the mechanisms underlying the association between technology-use and sleep during adolescence.

Adolescence is characterized by an evening chronotype preference with adolescents engaging in late bed and wake times.{{cite journal |last1=Roenneberg |first1=Till |last2=Kuehnle |first2=Tim |last3=Pramstaller |first3=Peter P. |last4=Ricken |first4=Jan |last5=Havel |first5=Miriam |last6=Guth |first6=Angelika |last7=Merrow |first7=Martha |title=A marker for the end of adolescence |journal=Current Biology |date=29 December 2004 |volume=14 |issue=24 |pages=R1038–R1039 |doi=10.1016/j.cub.2004.11.039 |pmid=15620633 |bibcode=2004CBio...14R1038R |url=https://pure.rug.nl/ws/files/6682390/2004CurrBiolRoennebergSupp.pdf |hdl=11370/c1bdc8cd-d823-4287-a5ef-0725d0833601 |s2cid=30441985 |hdl-access=free }} An evening chronotype is unique to the period of adolescence compared to childhood and adulthood which are characterized by a morning chronotype. Eveningness during adolescence is linked with increased substance use,{{cite journal |last1=Negriff |first1=Sonya |last2=Dorn |first2=Lorah D. |last3=Pabst |first3=Stephanie R. |last4=Susman |first4=Elizabeth J. |title=Morningness/eveningness, pubertal timing, and substance use in adolescent girls |journal=Psychiatry Research |date=28 February 2011 |volume=185 |issue=3 |pages=408–413 |doi=10.1016/j.psychres.2010.07.006 |pmid=20674040 |pmc=3032034 }} worse overall mood,{{cite journal |last1=Díaz-Morales |first1=Juan Francisco |last2=Escribano |first2=Cristina |last3=Jankowski |first3=Konrad S. |title=Chronotype and time-of-day effects on mood during school day |journal=Chronobiology International |date=2 January 2015 |volume=32 |issue=1 |pages=37–42 |doi=10.3109/07420528.2014.949736 |pmid=25153134 |s2cid=15020688 |url=http://eprints.ucm.es/32635/1/Diaz_Morales_Escribano_Jankowski_2015_chronotype_timeofday_mood_CI_eprint.pdf }} poor diet,{{Cite journal|last1=Fleig|first1=Daniel|last2=Randler|first2=Christoph|date=2009-04-01|title=Association between chronotype and diet in adolescents based on food logs|journal=Eating Behaviors|volume=10|issue=2|pages=115–118|doi=10.1016/j.eatbeh.2009.03.002|pmid=19447353|issn=1471-0153}} increased depressive symptoms,{{Cite journal|last1=Dagys|first1=Natasha|last2=McGlinchey|first2=Eleanor L.|last3=Talbot|first3=Lisa S.|last4=Kaplan|first4=Katherine A.|last5=Dahl|first5=Ronald E.|last6=Harvey|first6=Allison G.|date=2012|title=Double trouble? The effects of sleep deprivation and chronotype on adolescent affect|journal=Journal of Child Psychology and Psychiatry|language=en|volume=53|issue=6|pages=660–667|doi=10.1111/j.1469-7610.2011.02502.x|issn=1469-7610|pmc=3311740|pmid=22188424}} increased anxiety symptoms,{{Cite journal|last1=Alvaro|first1=Pasquale K.|last2=Roberts|first2=Rachel M.|last3=Harris|first3=Jodie K.|date=2014-08-01|title=The independent relationships between insomnia, depression, subtypes of anxiety, and chronotype during adolescence|journal=Sleep Medicine|volume=15|issue=8|pages=934–941|doi=10.1016/j.sleep.2014.03.019|pmid=24958244|issn=1389-9457}} and poor emotion regulation.{{Cite journal|last1=Owens|first1=Judith A.|last2=Dearth-Wesley|first2=Tracy|last3=Lewin|first3=Daniel|last4=Gioia|first4=Gerard|last5=Whitaker|first5=Robert C.|date=2016-12-01|title=Self-Regulation and Sleep Duration, Sleepiness, and Chronotype in Adolescents|journal=Pediatrics|language=en|volume=138|issue=6|pages=e20161406|doi=10.1542/peds.2016-1406|issn=0031-4005|pmid=27940688|doi-access=free}} Beyond conveying bed and wake times, chronotype is also indicative of optimal times of functioning. For instance, researchers tested adolescents on their executive functioning performance at two times: once at a time that is optimal for chronotype (i.e. evening for evening chronotypes vs. morning for morning chronotypes) and once at a time that is suboptimal for chronotype (i.e. morning for evening chronotypes vs. evening for morning chronotypes). They found that morning adolescents tested in the morning performed better than in the evening, and evening chronotype adolescents tested in the evening performed better than in the morning.{{Cite journal|last1=Hahn|first1=Constanze|last2=Cowell|first2=Jason M.|last3=Wiprzycka|first3=Ursula J.|last4=Goldstein|first4=David|last5=Ralph|first5=Martin|last6=Hasher|first6=Lynn|last7=Zelazo|first7=Philip David|date=2012|title=Circadian rhythms in executive function during the transition to adolescence: the effect of synchrony between chronotype and time of day|journal=Developmental Science|language=en|volume=15|issue=3|pages=408–416|doi=10.1111/j.1467-7687.2012.01137.x|issn=1467-7687|pmc=4103784|pmid=22490180}}

The Pittsburgh Sleep Quality Index (PSQI) is a well-validated and widely used self-report questionnaire that measures sleep quality.{{cite journal |last1=Buysse |first1=Daniel J. |last2=Reynolds |first2=Charles F. |last3=Monk |first3=Timothy H. |last4=Berman |first4=Susan R. |last5=Kupfer |first5=David J. |title=The Pittsburgh sleep quality index: A new instrument for psychiatric practice and research |journal=Psychiatry Research |date=1 May 1989 |volume=28 |issue=2 |pages=193–213 |doi=10.1016/0165-1781(89)90047-4 |pmid=2748771 |s2cid=13035531 }} Nineteen items are combined to create seven component scores of sleep, and those component scores are then used to create an overall “global score” of sleep quality. The seven components consist of subjective sleep quality, sleep disturbances, sleep duration, sleep latency, habitual sleep efficiency, use of sleep medications, and daytime dysfunction. The PSQI has a high internal reliability (Cronbach's alpha = 0.83).{{cite web | url=https://consultgeri.org/try-this/general-assessment/issue-6.1.pdf | title=Try This: Series | Hartford Institute for Geriatric Nursing }} The PSQI has been used in many studies assessing adolescent sleep quality.

Actigraph watches are commonly used to gather objective measures of sleep.{{cite journal |last1=Martin |first1=Jennifer L. |last2=Hakim |first2=Alex D. |title=Wrist Actigraphy |journal=Chest |date=2011 |volume=139 |issue=6 |pages=1514–1527 |doi=10.1378/chest.10-1872 |pmid=21652563 |pmc=3109647 }} The watch is worn on the non-dominant wrist and measures sleep using body movement. Data gathered from the watch includes sleep duration, number of awakenings, total minutes of nighttime awakenings, and latency.{{Cite journal|last1=Sadeh|first1=Avi|last2=Sharkey|first2=M.|last3=Carskadon|first3=Mary A.|date=1994-05-01|title=Activity-Based Sleep-Wake Identification: An Empirical Test of Methodological Issues|url=https://academic.oup.com/sleep/article/17/3/201/2749453|journal=Sleep|language=en|volume=17|issue=3|pages=201–207|doi=10.1093/sleep/17.3.201|pmid=7939118|issn=0161-8105|doi-access=free|url-access=subscription}}

The first valid and reliable measure of chronotype was created by Horne and Östberg (1976): Morningness-Eveningness Questionnaire (MEQ) contains 19 items tapping sleep and wake time preferences.{{cite report | last1=Urbán | first1=Róbert | last2=Magyaródi | first2=Tímea | last3=Rigó | first3=Adrien | title=Reduced Horne Östberg Morningness-Eveningness Questionnaire--Hungarian Version | date=2015-02-09 | doi=10.1037/t36759-000 | page=}} Sample items include “Assuming adequate environmental conditions, how easy do you find getting up in the mornings?” and “Considering your own ‘feeling best’ rhythm, at what time would you get up if you were entirely free to plan your day?”. The questionnaire consists of both Likert and timescale items, and items are scored to obtain a composite score. Since its creation, the MEQ has been validated in some adolescent and young adult samples.{{Cite journal|last1=Chelminski|first1=Iwona|last2=Ferraro|first2=F. Richard|last3=Petros|first3=Thomas|last4=Plaud|first4=Joseph J.|date=1997-10-01|title=Horne and Ostberg questionnaire: A score distribution in a large sample of young adults|journal=Personality and Individual Differences|volume=23|issue=4|pages=647–652|doi=10.1016/S0191-8869(97)00073-1|issn=0191-8869}}{{Cite journal|last1=MECACCI|first1=LUCIANO|last2=ZANI|first2=ALBERTO|date=1983-12-01|title=Morningness-eveningness preferences and sleep-waking diary data of morning and evening types in student and worker samples|journal=Ergonomics|volume=26|issue=12|pages=1147–1153|doi=10.1080/00140138308963450|issn=0014-0139|pmid=6686817}}{{Cite journal|last1=Inomata|first1=Yoshiyuki|last2=Echizenya|first2=Masaru|last3=Takeshima|first3=Masahiro|last4=Shimizu|first4=Kazumi|last5=Shimizu|first5=Tetsuo|date=2014-07-14|title=Validity and reliability of the Japanese version of the Morningness-Eveningness Questionnaire evaluated from actigraphy|journal=Sleep and Biological Rhythms|volume=12|issue=4|pages=289–296|doi=10.1111/sbr.12073|s2cid=146785567 |issn=1446-9235}} Early assessments of this questionnaire's psychometric properties revealed that the scale has good internal consistency (a = .82).{{Cite journal|last1=Smith|first1=Carlla S.|last2=Reilly|first2=Christopher|last3=Midkiff|first3=Karen|date=1989|title=Evaluation of three circadian rhythm questionnaires with suggestions for an improved measure of morningness.|journal=Journal of Applied Psychology|volume=74|issue=5|pages=728–738|doi=10.1037/0021-9010.74.5.728|pmid=2793773|issn=0021-9010}}

{{reflist}}

Category:Sleep physiology