Triple Vulnerability? Circadian Tendency, Sleep Deprivation and Adolescence
Phase: NA
Conditions: Eveningness/Sleep
Sponsor: University of California, Berkeley

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 Title:  
Triple Vulnerability? Circadian Tendency, Sleep 
Deprivation and Adolescence  
CPHS Number: 
2012-02-4007 (Date of 1st approval: March, 14 2012) 
 
Clinicaltrials.gov Number:  
NCT01828320 (Date of 1st release: April, 02 2013)  
 
Amendment 1 Date: 04/09/2013 
  
Amendment 3 Date: 12/16/2014 
 
Amendment 3 Date: 12/15/2015 
 
 
Amendment 5 Date: 05/13/2016 
 
 
Amendment 7 Date: 10/25/2016 
 
 
Amendment 9 Date: 06/08/2018 
 
 
 
Amendment 4 Date: 04/04/2016 
  
 
Amendment 6 Date: 06/21/2016 
 
 
Amendment 8 Date: 10/05/2017 
 
 
Amendment 10 Date: 04/16/2019 
 
 
Sponsor Eunice Kennedy Shriver National Institute of Child Health and Human Developmen
1 Center Drive, Bethesda, MD 20892 USA  
Study Principal Investigator  
Allison G. Harvey, Ph.D. Psychology Department, 2121 Berkeley Way, 3rd floor. University o
California, Berkeley, CA 94720-1650. USA. email: aharvey@berkeley.edu 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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TABLE OF CONTENTS 
Table of Contents ……….…………………………………….………….…….………………………2 
Figure 1: Study Diagram ……….…………………………………….………….…….………………3 
1. PURPOSE ……….………………………………….………….……….……………………………4 
2. METHOD……….…………………………………….………….……….…………………………..5 
2.1 STUDY DESIGN ................................................................................................................................5 
2.2 PARTICIPANTS .................................................................................................................................5 
2.3 TREATMENTS ...................................................................................................................................5 
2.3.1 Transdiagnostic Sleep and Circadian Intervention for Youth (TranS-C) ........................................6 
2.3.2. Psychoeducation (PE) .....................................................................................................................6 
3. MEASURES……….…………………………………….………….……….………………………..7 
3.1. DIAGNOSIS.......................................................................................................................................7 
3.2. SLEEP OUTCOMES..........................................................................................................................7 
3.2.1 Sleep diary.........................................................................................................................................7 
3.3. CIRCADIAN OUTCOMES................................................................................................................7 
3.3.1 Children’s Morningness-Eveningness Preferences Scale (CMEP) .................................................7 
3.3.2 Dim Light Melatonin Onset (DLMO) ...............................................................................................7 
3.4. FUNCTIONING IN FIVE HEALTH DOMAINS..............................................................................8 
3.4.1. Youth Self-Report Composite Risk Score ........................................................................................8 
3.4.2. Youth Ecological Momentary Assessment (EMA) Composite Risk Score........................................9 
3.4.3. Parent-Reported Composite Risk Score via the Child Behavior Checklist (CBCL .......................10 
3.5. MEDICATIONS TRACKING LOG.................................................................................................10 
3.6. CREDIBILITY/EXPECTANCY QUESTIONNAIRE (CEQ) ........................................................10 
4. TIMELINE FOR ASSESSMENTS AND TREATMENT……………………………….……….10 
5. DATA ANALYSIS……………………………….…………………………………….…………...11 
Table 1: Descriptions of Evidence Based Treatment sources………………………………………12 
Table 2: Calculation of Sleep Diary Variable…………………….…………………………….……13 
References…………………….……………………………….…………………………….…………14 

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FIGURE 1: STUDY DIAGRAM 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Assessed for Eligibility 
Baseline assessment (pre-treatment) 
Not eligible or decline 
Randomized (Allocated to Trans-C or PE) 
Treatment phase (6 individual, weekly 50-minute sessions) 
 
Post-Treatment Assessment 
6-month Follow-up Assessment 
12-month Follow-up Assessment 

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1. PURPOSE 
 
Adolescence is a health paradox: it is the healthiest time of life, yet a time of great risk and vulnerability 
with potential for devastating long term consequences, including poorer health, school failure and 
academic underperformance, engagement in risky impulsive behaviors, abuse of substances, increased 
risk of accidents, relationship difficulties with peers and parents, and the development of emotional and 
behavioral disorders. Hence, there is an urgent need to identify novel modifiable mechanisms contributing 
to risk and vulnerability among teens. 
 
The modifiable mechanism targeted in this study is ‘eveningness’. Teens who exhibit an evening 
circadian tendency (‘night-owls’) follow a delayed sleep schedule, increasing activity later in the day and 
both going to sleep and getting up later, compared to morning types (‘larks’). The circadian tendency 
toward eveningness during adolescence arises from a confluence of psychosocial, behavioral and 
biological factors and is an important contributor to, and maybe even cause of, vicious cycles that escalate 
vulnerability and risk for poor health and major forms of psychopathology. Indeed, eveningness is 
associated with an extremely wide-range of adverse outcomes including poorer academic performance, 
poorer self-regulation, greater use of substances, greater tendency for impulsivity and more depression 
and anxiety. While the basic biological shift toward eveningness during puberty may be difficult to 
modify, the psychosocial and behavioral contributors are modifiable. Moreover, modifying the 
psychosocial and behavioral contributors will eliminate key factors that exacerbate the pubertal biological 
shift.  
 
This conceptualization derives from evidence that biological changes in the circadian system at puberty 
lead to a shift in sleep timing preferences toward a delayed sleep phase. This effect is compounded by 
psychosocial changes including less parental control, increased access to stimulating social activities 
(movies, music, internet, texting, cell phones) and intake of alcohol and substances that contribute to 
sleep disruption. The social influences are synergistic with biological tendencies toward phase delay and 
can spiral quickly into a pattern of extremely delayed bedtimes. Yet, school or work usually requires a 
fixed early wake-up time. These forces converge to constrain the time available for sleep, resulting in 
high rates of insufficient sleep among youth. Compounding the negative cycle, most attempts to “catch-
up” on sleep occur on weekends with an extremely phase-delayed schedule. This is a critical problem 
because the human circadian system adapts more easily to phase delays; endogenous rhythms are able to 
re-set quickly to later bed and wake times, but have more difficulty accommodating to phase advances 
(earlier sleep schedules). The problematic result is that large numbers of youth are struggling with the 
burdens of eveningness, sleep deprivation and the consequences of repeated circadian shifts. This is of 
particular concern for rapidly developing teens because adequate sleep is critical for optimal brain 
development. 
 
This research will advance current knowledge on the role of eveningness as a mechanism contributing to 
poorer outcomes during adolescence. We aim to reduce eveningness among 10-18 year olds via an 
innovative intervention; the Transdiagnostic Sleep and Circadian Intervention (TranS-C) which integrates 
elements from four evidence-based treatments (Cognitive Behavior Therapy for Insomnia, Interpersonal 
and Social Rhythm Therapy, Chronotherapy, and Motivational Interviewing) derived from basic research 
on the circadian system. We will randomly allocate adolescents (10-18 year olds) with an evening 
circadian tendency, and who are ‘at risk’ in at least one of five health domains (emotional, cognitive, 
behavioral, social, physical), to either: (a) TranS-C or (b) Psychoeducation. Measures will be taken pre-
treatment, at the end of treatment, and at 6 and 12 months post-treatment.  
 
We aim to evaluate if an intervention to reduce eveningness among adolescents improves sleep and 
functioning in five health-relevant domains (emotional, cognitive, behavioral, social and physical) in the 
short and long term. The major hypothesis to be tested is that TranS-C, relative to Psychoeducation, will 

5 
 
 
 
improve sleep and circadian function, advance the timing of the endogenous circadian phase via the dim 
light melatonin onset protocol (DLMO), and decrease risk across the five health domains (emotional, 
cognitive, behavioral, social, and physical).  
 
2. METHOD 
 
2.1. Study Design 
 
Based in a university clinic, youth will be randomly assigned, stratified by sex and age (10-14, 15-18), in 
a 1:1 parallel group design, to receive either TranS-C or PE. Sibling pairs will be randomized to the same 
condition. 
 
Assessors will be blind to treatment allocation. Sequentially numbered, opaque, sealed envelopes will be 
generated using a computer-generated random number list. A project coordinator will conduct 
randomization after all eligibility assessments are completed. Assessments will be conducted at baseline 
and at the end of treatment. The Committee for the Protection of Human Subjects approved the study.  
 
2.2. Participants 
 
Participants will be recruited through clinicians or advertisements. Individuals will be eligible if they (a) 
are between 10 and 18 years old, living with a parent or guardian, and attending a class/job by 9am at 
least 3 days per week; (b) are fluent in English; (c) are able and willing to give informed assent; and 
(d) report eveningness as demonstrated by scoring within the lowest quartile of the Children’s 
Morningness-Eveningness Preferences Scale (CMEP; 27 or lower) and have a 7-day sleep diary showing 
a sleep onset time of 10:40pm or later for 10-13 year olds, 11pm or later for 14-16 year olds, and 
11:20pm or later for 17-18 year olds at least 3 nights per week.61,62 In addition, this sleep pattern will have 
to have been present for the past 3 months. Finally, participants will have to fall into an ‘at risk’ range on 
measures of at least one of the five health domains reviewed above.  
 
Exclusion criteria will be (a) an active, progressive physical illness or neurological degenerative disease 
directly related to the onset and course of the sleep disturbance; (b) evidence of obstructive sleep apnea, 
restless legs syndrome, or periodic limb movement disorder59; (c) significantly impairing pervasive 
developmental disorder; (d) bipolar disorder, schizophrenia, or another current Axis I disorder if there is a 
risk of harm if treatment is delayed. Participants will cease taking medications that alter sleep (e.g., 
hypnotics) 4 weeks prior to the assessment (2 weeks for melatonin) or will be excluded. Finally, history 
of substance dependence in the past six months or current suicide risk sufficient to preclude treatment on 
an outpatient basis will be exclusionary.  
 
In other words, receipt of another sleep treatment will be the only type of treatment excluded. We want to 
be sure that any improvements in sleep could be attributed to TranS-C or PE, not the other sleep 
treatment. Other medications will be allowed. A medication-free group would be unrepresentative. We 
will also include youth with Axis I psychiatric comorbidity (except for bipolar disorder and 
schizophrenia), even if they are receiving treatment for that comorbidity. 
 
2.3. Treatments 
 
Therapists will be doctoral or master’s level. Weekly supervision will be conducted separately for TranS-
C and PE. Sessions will be audio recorded. Treatment integrity will be evaluated by AGH for TranS-C 
with the Cognitive Therapy Rating Scale (CTRS)63 and by NZ for PE on a 1-100 scale, on which higher 
scores will be awarded for alliance building, reflective listening, and providing PE without emphasizing 
behavior change.  

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A checklist of elements specific to TranS-C and PE will be used to rate presence/absence and focus on 
behavior change (a distinguishing feature of the treatments) for a random subset of tapes. 
 
Treatment will involve 6 individual, weekly 50 minute sessions delivered during the school year to 
minimize the impact of summer schedule variability41. During the treatment phase, youth in TranS-C will 
be encouraged to complete their own sleep diary each morning for the purpose of treatment planning 
(particularly for sleep restriction). Youth in PE will not complete a sleep diary. 
 
2.3.1. Transdiagnostic Sleep and Circadian Intervention for Youth (TranS-C)  
 
TranS-C1 is grounded in sleep and circadian basic science and combines elements from four evidence-
based interventions: Cognitive Behavior Therapy for Insomnia42,64,65, Interpersonal and Social Rhythm 
Therapy66, Chronotherapy67 and Motivational Interviewing48 (See Table 1). TranS-C is a modular 
approach which allows the treatment sessions to be focused on the specific sleep problem experienced by 
each patient. The goal is to reverse maintaining psychosocial, behavioral and cognitive processes via 4 
cross-cutting modules, 4 core modules and 7 optional modules. 
 
● The four Cross Cutting Modules are: case formulation; education; behavior change and 
motivation; goal setting. “Cross-cutting” modules are introduced in the first session and are 
typically featured every session thereafter. 
● The four Core Modules are: establishing regular sleep-wake times including learning a wind-
down and wake-up routine; improving daytime functioning; correcting unhelpful sleep-related 
beliefs; and maintenance of behavior change. “Core modules” apply to the vast majority of 
patients. 
● The Optional Modules are: improving sleep efficiency; reducing time in bed; dealing with delayed or 
advanced phase; reducing sleep-related worry/vigilance; promoting compliance with CPAP/exposure 
therapy for claustrophobic reactions to CPAP; negotiating sleep in a complicated environment and 
reducing nightmares. “Optional modules” are used less commonly and only if indicated by the case 
formulation.  
The modular format will allow the treatment sessions to be focused on the specific sleep problem experienced 
by each patient. The treatment manual recommends a specific order in which modules are typically completed 
but suggests that clinicians be sensitive to differences between patients as to which processes are maintaining 
their distress and to address those processes at an earlier stage of treatment. Specific assessments are 
recommended to guide the treatment provider as to when the optional modules should be used. 
 
 
2.3.2. Psychoeducation (PE) 
 
Psychoeducation (PE) is an active comparison treatment associated with sleep improvement.30 PE 
constitutes a conservative control for treatment location, experience and skill level of the therapists, the 
number and quality of handouts, therapist attention, amount and frequency of contact with the therapist, 
duration of treatment, and beliefs and expectations about the efficacy of treatment held by the teens. 
Sessions will focus on the inter-relationship between sleep, stress, diet, health, exercise, accidents, and 
mood. These sessions will involve obtaining a detailed description from the teen about their experience 
with the topic and general education. Participants will also be given the choice of sampling meditation, 
yoga, and/or outdoors appreciation. There will be no explicit focus on sleep except briefly mentioning 
sleep as a common contributor to each topic. If a participant raises issues related to sleep or requests 

7 
 
 
 
advice on implementing change, the therapist will respectfully return to the content of the session. The 
emphasis will be on providing information but not on specifically facilitating behavior change. 
 
3. MEASURES  
 
Except where specified, assessments will be administered before and after treatment. Assessments will be 
audio recorded. A random subset will be reviewed. 
 
3.1. Diagnosis 
 
The KSADS69 will be administered separately to youth and one parent/caregiver to assess for participant 
current and lifetime Axis I disorders at the pre-treatment assessment.  
 
3.2. Sleep Outcomes 
 
3.2.1 Sleep Diary.15  
 
An a priori decision was made to investigate weeknight average total sleep time (TST) and bedtime (BT) 
average as primary outcomes to best capture the sleep problems of interest.60 Secondary outcomes will be 
the discrepancy between weeknight and weekends for TST, BT, and waketime (WUP). Trained research 
assistants will phone the participants each morning to collect their sleep diary. In scheduling the call, the 
participants will specifically be told to not use the call as an alarm clock and to select a time as close as 
possible to rise time but after they are already out of bed. The training of the research assistants will 
specifically include not engaging in conversation other than collecting the sleep diary data. (See Table 2 
for calculations of sleep diary variables). 
 
Other secondary outcomes will be Sleepiness Scale16, Pittsburgh Sleep Quality Index (PSQI)18,26 and 
CBCL Sleep Composite (parent report).8  
 
3.3. Circadian Outcomes 
 
3.3.1 Children’s Morningness-Eveningness Preferences Scale (CMEP) 9  
 
CMEP will be a primary outcome. Scores range from 10 (Extreme evening preference) to 43 (Extreme 
morning preference).  
 
3.3.2 Dim Light Melatonin Onset (DLMO)  
 
DLMO will be a secondary outcome. DLMO is the gold standard index of the endogenous circadian 
phase30. DLMO is defined as the interpolated time at which melatonin exceeds 3.0 pg/ml. The selection of 
this threshold is based upon prior experience with melatonin as a marker of circadian phase and the visual 
inspection of each participant’s DLMO record 70. This method of DLMO assessment will also provide a 
circadian phase estimate for the highest percentage of participants, including participants with low 
melatonin production. 
 
Melatonin is a hormone produced by the pineal gland; its levels remain low during the daytime, begin to 
increase approximately 2 hours prior to habitual bedtime, and peak in the first part of the night. Synthesis 
and production of melatonin is predominantly regulated by the light-dark cycle.33 Circulating melatonin 
levels are a preferred circadian marker because they are comparatively robust and less prone to masking 
from other external influences compared to measures like to core body temperature, cortisol, and heart 
rate.34 However, bright light in the evening can suppress or “mask” nighttime melatonin production,32 

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which necessitates its measurement in dim light conditions. 
 
DLMO will be assessed with the serial saliva sampling method one night before and after treatment in an 
overnight stay in the Psychology Department at UC Berkeley based on established protocol70. Several 
methods have been used to assess melatonin, including its concentration in plasma or salvia and its 
metabolite (aMTS6S) in plasma or urine.39 We will collect saliva as it has become the preferred sampling 
method as it is non-invasive and more acceptable to patients.39 Light levels will be determined using 
Fisher Scientific Extech Light Meter 407026 (Pittsburgh, PA). Following current convention, dim light 
(<50 lux, but preferably <20 lux35,36) will be initiated 1 hour before the earliest melatonin onset.37,38 
 
Thirteen saliva samples will be collected for each participant before and after treatment, beginning 5.5 
hours before average bedtime (computed from 7 nights of sleep diary) and ending 30 minutes after 
average bedtime. Saliva (~1 ml) samples will be collected in 30-minute intervals in dim light (< 50 lux) 
using untreated Sarsedt Salivettes (Starstedt, Germany). Saliva samples will be centrifuged at 3300 RPM 
for 5 minutes. If <1mL saliva is yielded after centrifuging, samples will be centrifuged for an additional 5 
minutes at 3500 RPM. Samples will be frozen and stored at -80 °C and later assayed for melatonin by 
SolidPhase (Portland, Maine) using radioimmunoassay test kits (APLCO Diagnostics, Windham, NH). 
Assay sensitivities will be 0.3 pg/mL and the minimum detectable dose will be 0.05 pg/mL. Mean intra- 
and inter-assay coefficients of variation (CV) will be 7.9 and 9.4%, respectively. 40 Saliva samples will be 
collected from all randomized participants.  
 
3.4. Functioning in five health domains.  
 
For each of the five health domains (i.e., emotional, cognitive, behavioral, social, and physical health), 
three clusters of composite scores will be calculated using the cumulative risk index71,72 by taking the 
mean of standardized summary scores for specific measures within that domain.  
 
3.4.1. Youth Self-Report Composite Risk Score.  
 
The first cluster will be the Youth Self-Report Composite Risk Score (primary) which will be derived from 
psychometrically validated questionnaires representing each of the five health domains.  
 
● Domain 1. Emotional health will be indexed by a composite of the 17-item Children’s Depression 
Rating Scale-Revised (CDRS; range 17-113; higher scores = worse depression)41 and the 39-item 
Multidimensional Anxiety Scale for Children (MASC; range 0-117; higher scores = worse 
anxiety).42  
● Domain 2. Cognitive Health will be indexed by a composite of the 20-item Attentional Control 
Scale (ACS)43 (range 4-80; higher scores = better attentional control) and the six school-related 
items from the Youth Social Adjustment Scale – Self Report (YSAS).44  
● Domain 3. Behavioral Health will be indexed by a composite of the 8-item Sensation Seeking 
Scale for Children45 and the Alcohol and Substance Use Questionnaire46 to assess consumption of 
caffeine, alcohol, and recreational drugs in the past 30 days (1-7 rating scale; higher scores= more 
frequent use). For the purpose of the present study we will add questions on caffeine and energy 
drinks to the latter.   
● Domain 4. Social Health will be indexed by the average of three subscales (ie, friends, family, 
romantic relationships) from the Youth Social Adjustment Scale – Self Report44 (higher scores = 
more impaired adjustment).  

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● Domain 5. Physical Health will be indexed by the composite of the Modifiable Activity 
Questionnaire for Adolescents (MAQ; Calculated as the number of hours per week being 
active/exercising; higher scores = greater numbers of active hours)47 and the Physical Health 
Questionnaire-15 (PHQ-15; range 0-30; higher scores = worse somatic complaints).48  
3.4.2. Youth Ecological Momentary Assessment (EMA) Composite Risk Score. 
 
The second cluster will be the Youth Ecological Momentary Assessment (EMA) Composite Risk Score 
which will be derived from phone calls twice per day on weekdays and four times per day on weekends. 
The questions asked during the calls will be adapted from Silk et al73. The rationale for including EMA is 
to index ‘real world’ functioning in each of the five health domains.  
 
● Domain 1. Emotional Health will be indexed with a short version of the Positive and Negative 
Affect Schedule for Children50; 4 items measuring positive affect and 5 items measuring negative 
affect will be rated on a 5-point Likert scale. A Positivity Ratio will be calculated. Diener 51 
proposed that a high ratio of positive to negative emotion (the positivity ratio) predicts subjective 
well-being. Prior research has shown that sleep deprivation and eveningness are associated with a 
lower positivity ratio.52  
● Domain 2. Cognitive Health. Using questions adapted from previous research,43 participants will 
be asked ‘At the moment the phone rang, what were you doing?’. Participants will then be asked 
to rate their concentration, distractedness and focus related to this task on a 5 point Likert scale. 
The response to these ratings will be averaged.  
● Domain 3. Behavioral Health. Participants will be asked about eating, drinking or chewing gum 
or smoking at the moment the phone rang. We will tabulate the average weekly frequency and 
intake of junk food, caffeine, alcohol, nicotine and other substances.  
● Domain 4. Social Health. We will assess who the participant is with at the time of the call. 
Positivity Ratio (see EMA for Emotional Health) will be calculated when the participant is alone, 
with a family member or with a friend.  
● Domain 5. Physical Health. Physical activity will be assessed using questions from previous 
research53. We will calculate a total of the binary variable (active = 1 and inactive = 2).54 
The Youth Ecological Momentary Assessment (EMA) Composite Risk Score will be derived by taking 
the average scores for the week for each domain. 
 
Participants will receive calls from a trained interviewer for one week at pre-treatment and one week at 
post-treatment. The frequency of the assessments will be twice on weekdays between 4 and 9pm and four 
times on weekends between 11am and 9pm, with a total of 36 calls for the entire study. Participants will 
be instructed to turn off their cell phones during school time. If a participant does not answer on the first 
attempt, the call will be attempted again immediately and then again after 5 minutes. There will be at least 
30 minutes between each call. Each call will consist of a brief structured interview to evaluate the five 
health-relevant risk domains. The interview delivered at each phone call will be based on Silk et al.49 and 
adapted to index each of the five health domains. The coding of the EMA will also be adapted from the 
methods of Silk et al.49 Specifically, the interview responses will be transcribed verbatim into a primary 
database. From that database, five coders will independently code a subset of the data (5%) with 
agreement with an "expert coder" (NG). In order to be a certified coder, coders will have to match at over 
80% accuracy with the expert coder for a minimum of 54 consecutive calls. Then each coder will 
independently code a subset of the data.  
 

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3.4.3. Parent-Reported Composite Risk Score via the Child Behavior Checklist (CBCL). 55 
 
The third cluster will be the Parent-Reported Composite Risk Score comprised of a composite score of 
parent responses to CBCL subscales representing the five health domains. Parents will rate this 113-item 
assessment of psychological and behavioral functioning of their child (rating scale 0-2; higher scores = 
more problematic behaviors). CBCL subscales will be used as the parent-reported composite risk score.  
 
● Domain 1. Emotional Health will be assessed with the Anxious/Depressed and 
Withdrawn/Depressed subscale.  
● Domain 2. Cognitive Health will be assessed with the Thought Problems and Attention Problems 
subscale.  
● Domain 3. Behavioral Health will be assessed with the Rule-Breaking Behavior and Aggressive 
Behavior subscale.  
● Domain 4. Social Health will be assessed with the Social Problems subscale. 
● Domain 5. Physical Health will be assessed with the Somatic Complaints subscale. 
3.5. Medications Tracking Log. 
 
A Medications Tracking Log will be completed.  
 
3.6. Credibility/expectancy questionnaire (CEQ)74  
 
The CEQ will be administered at the end of the second therapy session to index expectation of 
improvement and credibility of treatment.  
 
4. TIMELINE FOR ASSESSMENTS AND TREATMENT 
 
Study flow is illustrated in Figure 1. Adolescents and parents/guardians will be screened via telephone. 
Eligible adolescents will complete a sleep diary for 7 nights to ascertain the presence of Inclusion. If met, 
an in-person assessment will be conducted during which the KSADS and questionnaires will be 
completed. If the participant continued to meet criteria, the activities from this point forward will be 
conducted within the school semester because holiday schedules differ markedly during adolescence41.  
 
To determine DLMO collection times and wake-up times, an additional 7 nights of sleep diary will be 
collected immediately prior to the overnight stay in the lab. The overnight assessment of DLMO will be 
conducted in the Psychology Department at the University of California, Berkeley and will be held on a 
Friday or Saturday night. The rationale for this choice is to ensure the protocol doesn’t interfere with 
school. Groups of 1 to 5 participants will be tested each evening. Each participant will have their own 
bedroom. We will ensure the participant is exposed to <50 lux at all times, but prefer <20 lux. The 
lighting in each bedroom will be replaced with dim light bulbs. When the participant leaves the bedroom 
(e.g., to go to the bathroom) they will wear welding glasses. A light metre will be used to check the 
illumination of computer and cell phone screens. The light meter will be held next to participants eyes to 
measure the amount of light the participant is exposed to. Across the evening the participants will be 
allowed to engage in a narrow range of tasks that represent a standardized regiment of calm/quiet 
activities (e.g., reading, playing a board game, watching a movie, completing homework). We will assist 
the participants to set their computers/phones to the lowest brightness. In order to complete the DLMO 
protocol, the participant will stay up 45 minutes later relative to their usual school day bedtime. To 
minimize the impact of this, we will allow the participants to sleep in by 30 minutes relative to their usual 
school day waketime. The participant will arrive approximately 6.5 hours before their bedtime. If 
participants ingest anything except water before the saliva sample, they will rinse their mouths and 

11 
 
 
 
brushed their teeth with water. Ingestion of caffeine, fruits, chocolate, non-steroidal anti-inflammatory 
drugs, and alcohol will be prohibited. 
 
After the overnight, the participant will be randomized and complete a further 7 night sleep diary and 
answer phone calls to collect Ecological Momentary Assessment (EMA) data. This additional sleep diary 
will be collected so that sleep diary data will be concurrent with EMA. These measures will be the basis 
of the primary and secondary outcomes. Treatment will commence one week later.   
 
After treatment, the procedures for the overnight assessment to collect DLMO will be repeated, along 
with an in-person interview and 7-days of EMA and sleep diary. The participants will be reimbursed $30 
for participating in the pre- and post-treatment assessments and $40 for the 6-FU and 12-FU. Parents will 
be reimbursed $30 for participating in the pre- and post-treatment assessments, $20 for the 6-FU, and $20 
for the 12-FU. 
 
5. DATA ANALYSIS 
 
Sample size will be determined via power analysis. Power analyses will be conducted based on the 
average of Cohen’s d (0.48) across estimations of the effect of treatment on sleep duration (for sleep 
outcomes) and the five primary health outcomes. Specifically, for sleep outcomes Cohen’s d will be 
calculated from the pre-post deviation scores across TranS-C and Psychoeducation conditions. For the 
five health domains we will use: our pilot data for emotional health and behavioral health56 recent meta-
analyses for cognitive health and physical health57,58; and unpublished data from a collaborator’s lab for 
the impact of poor sleep on social interactions. G*Power 3.1 was used to estimate sample size using 
Cohen’s d = 0.48, assuming significance of 0.05 and power of at least 80%. Sixty nine participants are 
needed for each condition. We will recruit 20% more for potential attrition. There will be no interim 
analyses. 
 
Data analysis will be conducted in Stata 14 (StataCorp, 2015). All analyses will be adjusted for age and 
sex, which will be the stratification factors used during randomization. Using intent-to-treat32, multilevel 
modeling with maximum likelihood estimation with the assumption of missing at random will be used to 
examine continuous outcomes. The fixed component of the model will include stratification factors (age 
and sex), an indicator for time period (Time=0 pre-treatment, Time=1 post-treatment), an indicator for 
treatment condition (Treatment=1 TranS-C, Treatment=0 PE), and a Time by Treatment interaction term. 
The random part of the model will include a subject-specific random intercept and a time and subject-
specific error term. The treatment effect of interest will be the interaction, representing the difference in 
mean change from pre-treatment to post-treatment between TranS-C and PE. The model will also provide 
estimates of the mean pre-to-post change in the PE condition (coefficient of Time) and in the TranS-C 
condition (coefficient of Time plus interaction coefficient), and the significance of these changes will also 
be reported regardless of the significance of the interaction because PE may be an active control and can 
be beneficial. Using Hochberg’s40 procedure, the outcomes will be considered two subfamilies of 
analyses. The error rate in each subfamily will be controlled under 0.025 using the Hochberg’s step-up 
procedure, so that the overall family-wise error rate will not exceed 0.05. 

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Table 1. DESCRIPTIONS OF EVIDENCE BASED TREATMENT SOURCES FOR TRANS-C 
 
 
 
 
 
 
 
 
Source 
Description  
Source 1. 
Cognitive 
Behavior 
Therapy for 
Insomnia 
(CBT-I). 
There is robust evidence for CBT-I from multiple meta-analyses10-13 and a systematic review for CBT-I in adults4. The 
evidence for CBT-I among adolescents is small but promising.14-18 The studies conducted among youth to date include 
combining CBT-I components with mindfulness14 or bright light,16 delivering CBT-I over the internet or in a group18 or in a 
classroom setting,19 involving parents in the treatment 15 and including an emphasis on motivational interviewing.19 Although 
much more treatment research is needed, this emerging literature justified including a focus on CBT-I in TranS-C. In 
particular, TranS-C-Youth draws on the CBT-I components that increase homeostatic pressure to sleep (stimulus control and 
sleep restriction) and reduce arousal (cognitive therapy).   
 
 
 
 
 
Source 2. 
Delayed 
Sleep Phase 
Type (DSPT). 
The broader spectrum of eveningness, rather than the extreme end represented by the disorder DSPT, is very common in 
teens. So this will be our focus. TranS-C-Youth will be informed by the small treatment literature on DSPT in youth,16,20-22 as 
well as practice parameters23 that indicate evidence for timed light exposure (with a light box) and planned and regular sleep 
schedules (chronotherapy) in adults. TranS-C-Youth includes the latter two interventions, with adaptations. First, many 
people are not motivated to use a light box; hence, TranS-C-Youth aims to help patients develop habits of exposing 
themselves to natural morning light and evening dim light with youth-selected electronic curfews. Second, traditional 
chronotherapy involving progressively delaying bedtimes and waketimes until reaching the desired alignment can be highly 
disruptive to family and work schedules. Third, in a study of 1285 high school students in Norway, the majority of students 
with delayed sleep phase (8.4%) reported considerable difficulty advancing bedtimes.24 As such, in TranS-C-Youth we tend 
to adopt a planned sleep modification protocol involving moving bedtimes earlier by 20-30 minutes per week. We select this 
slow change approach on the basis of our clinical experience, which is mainly with teens who have a severe mental illness or 
who are ‘at risk’ in one or more domains of their lives. With these youth we have found this schedule to be achievable and we 
capitalize on the youth’s feeling a sense of accomplishment, which further increases motivation for change. However, it 
should be noted that it is possible that the schedule we are currently using in TranS-C might maintain a disrupted lifestyle 
among youth given that the process of changing times once per week could take 5 weeks to complete. Research to determine 
the ideal sleep modification for the various groups of youth, and that balances circadian and motivational processes, is 
needed. 
Source 3. 
Interpersonal 
and social 
rhythms 
therapy 
(IPSRT). 
IPSRT is a treatment approach that is designed to maintain stability in social rhythms. The evidence base for stabilizing 
circadian rhythms with IPSRT in bipolar disorder and depression is growing, including in adolescence.25-27 Teens tend to have 
irregular sleep/wake cycles and social and personal schedules. In particular, waking early on weekdays for school, college or 
work and then sleeping in on weekends28 can result in a chronically jet-lagged state to which the human circadian system 
cannot adjust. Accordingly, TranS-C-Youth includes aspects of IPSRT deigned to stabilize bed and wake rhythms, as well as 
other social rhythms (eg, meal times, socializing, exercise etc), drawing from the treatment manual developed by Frank et 
al.29 This is because the sleep and circadian systems are surprisingly sensitive to non-photic cues, including physical activity 
and social interaction. Hence, stabilizing these daily rhythms help stabilize the sleep-wake schedule.   

13 
 
 
 
Table 2: CALCULATIONS OF SLEEP DIARY VARIABLES 
 
Sleep Diary variables 
Calculation 
Total sleep time (TST) 
time in bed – sleep onset latency - wake after sleep onset - terminal 
wakefulness. 
Time in bed 
time getting into bed – time getting out of bed 
Sleep onset latency 
time to fall asleep 
Wake after sleep onset 
sum of the duration of each awakening after sleep onset 
Terminal wakefulness 
time getting out of bed for the day - time of the final awakening 
Bedtime 
time getting into bed 
Wakeup time 
time of final awakening 
Discrepancy between 
weeknights and weekends 
for total sleep time, bedtime, 
and wakeup time 
Weeknight average - weekend average for total sleep time, bedtime, 
wakeup time 
Note. Definition derived based on Buysse et al. (2006) and Carney et al (2012) 
References: Carney, C. E., Buysse, D. J., Ancoli-Israel, S., Edinger, J. D., Krystal, A. D., Lichstein, K. L., & Morin, 
C. M. (2012). The consensus sleep diary: standardizing prospective sleep self-monitoring. Sleep, 35(2), 287-302. 
Buysse, D. J., Ancoli-Israel, S., Edinger, J. D., Lichstein, K. L., & Morin, C. M. (2006). Recommendations for a 
standard research assessment of insomnia. Sleep, 29(9), 1155–1173. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

14 
 
 
 
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