Assessment of the cortisol awakening response: Expert consensus guidelines

Adam, 2006, Transactions among adolescent trait and state emotion and diurnal and momentary cortisol activity in naturalistic settings, Psychoneuroendocrinology, 31, 664, 10.1016/j.psyneuen.2006.01.010

Adam, 2006, Day-to-day dynamics of experience-cortisol associations in a population-based sample of older adults, Proc. Natl. Acad. Sci. U. S. A., 103, 17058, 10.1073/pnas.0605053103

Adam, 2009, Assessing salivary cortisol in large-scale, epidemiological research, Psychoneuroendocrinology, 34, 1423, 10.1016/j.psyneuen.2009.06.011

Almeida, 2009, Interindividual differences and intraindividual variability in the cortisol awakening response: an examination of age and gender, Psychol. Aging, 24, 819, 10.1037/a0017910

Badrick, 2007, The relationship between smoking status and cortisol secretion, J. Clin. Endocrinol. Metab., 92, 819, 10.1210/jc.2006-2155

Badrick, 2008, The relationship between alcohol consumption and cortisol secretion in an aging cohort, J. Clin. Endocrinol. Metab., 93, 750, 10.1210/jc.2007-0737

Bäumler, 2013, The cortisol awakening response in toddlers and young children, Psychoneuroendocrinology, 38, 2485, 10.1016/j.psyneuen.2013.05.008

Bäumler, 2014, Effect of a naturalistic prospective memory-related task on the cortisol awakening response in young children, Biol. Psychol., 103, 24, 10.1016/j.biopsycho.2014.08.005

Bäumler, 2014, The relation of the cortisol awakening response and prospective memory functioning in young children, Biol. Psychol., 99, 41, 10.1016/j.biopsycho.2014.02.011

Bhake, 2013, Automated 24h sampling of subcutaneous tissue free cortisol in humans, J. Med. Eng. Technol., 37, 180, 10.3109/03091902.2013.773096

Bouma, 2009, Adolescents’ cortisol responses to awakening and social stress; effects of gender, menstrual phase and oral contraceptives. The TRAILS study, Psychoneuroendocrinology, 34, 884, 10.1016/j.psyneuen.2009.01.003

Broderick, 2004, Salivary cortisol sampling compliance: comparison of patients and healthy volunteers, Psychoneuroendocrinology, 29, 636, 10.1016/S0306-4530(03)00093-3

Buchanan, 2004, Circadian regulation of cortisol after hippocampal damage in humans, Biol. Psychiatry, 56, 651, 10.1016/j.biopsych.2004.08.014

Buijs, 2003, The biological clock tunes the organs of the body: timing by hormones and the automatic nervous system, J. Endocrinol., 177, 17, 10.1677/joe.0.1770017

Buss, 2009, The maternal cortisol awakening response in human pregnancy is associated with the length of gestation, Am. J. Obstet. Gynecol., 201, 10.1016/j.ajog.2009.06.063

Chida, 2009, Cortisol awakening response and psychosocial factors: a systematic review and meta-analysis, Biol. Psychol., 80, 265, 10.1016/j.biopsycho.2008.10.004

Chrousos, 2009, Stress and disorders of the stress system, Nat. Rev. Endocrinol., 5, 374, 10.1038/nrendo.2009.106

Clements, 1998, The relationship between salivary cortisol concentrations in frozen versus mailed samples, Psychoneuroendocrinology, 23, 613, 10.1016/S0306-4530(98)00031-6

Clow, 2004, The awakening cortisol response: methodological issues and significance, Stress, 7, 29, 10.1080/10253890410001667205

Clow, 2010, The cortisol awakening response: more than a measure of HPA axis function, Neurosci. Biobehav. Rev., 35, 97, 10.1016/j.neubiorev.2009.12.011

Cole, 1992, Automatic sleep wake identification from wrist activity, Sleep, 15, 461, 10.1093/sleep/15.5.461

Coste, 1994, Reliability of hormonal levels for assessing the hypothalamic-pituitary-adrenocortical system in clinical-pharmacology, Br. J. Clin. Pharmacol., 38, 474, 10.1111/j.1365-2125.1994.tb04386.x

De Weerth, 2005, Cortisol awakening response in pregnant women, Psychoneuroendocrinology, 30, 902, 10.1016/j.psyneuen.2005.05.003

DeSantis, 2010, Concordance between self-reported and objective wakeup times in ambulatory salivary cortisol research, Int. J. Behav. Med., 17, 74, 10.1007/s12529-009-9053-5

DiMatteo, 2000, Depression is a risk factor for noncompliance with medical treatment, Arch. Intern. Med., 160, 2101, 10.1001/archinte.160.14.2101

DiMatteo, 2004, Social support and patient adherence to medical treatment: a meta-analysis, Health Psychol., 23, 207, 10.1037/0278-6133.23.2.207

Doane, 2010, Loneliness and cortisol: momentary, day-to-day, and trait associations, Psychoneuroendocrinology, 35, 430, 10.1016/j.psyneuen.2009.08.005

Doane, 2010, Associations between jet lag and cortisol diurnal rhythms after domestic travel, Health Psychol., 29, 117, 10.1037/a0017865

Doane, 2015, Latent trait cortisol (LTC) levels: reliability, validity, and stability, Psychoneuroendocrinology, 55, 21, 10.1016/j.psyneuen.2015.01.017

Dockray, 2008, The cortisol awakening response in relation to objective and subjective measures of waking in the morning, Psychoneuroendocrinology, 33, 77, 10.1016/j.psyneuen.2007.10.001

Edwards, 2001, Exploration of the awakening cortisol response in relation to diurnal cortisol secretory activity, Life Sci., 68, 2093, 10.1016/S0024-3205(01)00996-1

Edwards, 2001, Association between time of awakening and diurnal cortisol secretory activity, Psychoneuroendocrinology, 26, 613, 10.1016/S0306-4530(01)00015-4

Elder, 2014, The cortisol awakening response-applications and implications for sleep medicine, Sleep Med. Rev., 18, 195, 10.1016/j.smrv.2013.05.001

Evans, 2011, The diurnal cortisol cycle and cognitive performance in the healthy old, Int. J. Psychophysiol., 79, 371, 10.1016/j.ijpsycho.2010.12.006

Evans, 2012, The cortisol awakening response is related to executive function in older age, Int. J. Psychophysiol., 84, 201, 10.1016/j.ijpsycho.2012.02.008

Federenko, 2004, Free cortisol awakening responses are influenced by awakening time, Psychoneuroendocrinology, 29, 174, 10.1016/S0306-4530(03)00021-0

Fekedulegn, 2007, Area under the curve and other summary indicators of repeated waking cortisol measurements, Psychosom. Med., 69, 651, 10.1097/PSY.0b013e31814c405c

Figueiro, 2012, Short-wavelength light enhances cortisol awakening response in sleep-restricted adolescents, Int. J. Endocrinol., 2012, 10.1155/2012/301935

Figueiro, 2012, Comparisons of three practical field devices used to measure personal light exposures and activity levels, Light. Res. Technol., 45, 421, 10.1177/1477153512450453

Franz, 2013, Adult cognitive ability and socioeconomic status as mediators of the effects of childhood disadvantage on salivary cortisol in aging adults, Psychoneuroendocrinology, 38, 2127, 10.1016/j.psyneuen.2013.04.001

Fries, 2009, The cortisol awakening response (CAR): facts and future directions, Int. J. Psychophysiol., 72, 67, 10.1016/j.ijpsycho.2008.03.014

Frost, 2000, Correcting for regression dilution bias: comparison of methods for a single predictor variable, J. R. Stat. Soc. Ser. A, 163, 173, 10.1111/1467-985X.00164

Gaab, 2005, Reduced reactivity and enhanced negative feedback sensitivity of the hypothalamus-pituitary-adrenal axis in chronic whiplash-associated disorder, Pain, 119, 219, 10.1016/j.pain.2005.10.001

Gao, 2015, Quantitative analysis of estradiol and six other steroid hormones in human saliva using a high throughput liquid chromatography-tandem mass spectrometry assay, Talanta, 143, 353, 10.1016/j.talanta.2015.05.004

Garcia-Banda, 2014, Neuroticism and cortisol: pinning down an expected effect, Int. J. Psychophysiol., 91, 132, 10.1016/j.ijpsycho.2013.12.005

Gibson, 1999, Increased salivary cortisol reliably induced by a protein-rich midday meal, Psychosom. Med., 61, 214, 10.1097/00006842-199903000-00014

Golden, 2014, Salivary cortisol protocol adherence and reliability by socio-demographic features: the multi-ethnic study of atherosclerosis, Psychoneuroendocrinology, 43, 30, 10.1016/j.psyneuen.2014.01.025

Granger, 2007, Blood contamination in children's saliva: prevalence, stability, and impact on the measurement of salivary cortisol, testosterone, and dehydroepiandrosterone, Psychoneuroendocrinology, 32, 724, 10.1016/j.psyneuen.2007.05.003

Granger, 2009, Medication effects on salivary cortisol: tactics and strategy to minimize impact in behavioral and developmental science, Psychoneuroendocrinology, 34, 1437, 10.1016/j.psyneuen.2009.06.017

Gribbin, 2012, The cortisol awakening response (CAR) in 2- to 4-year-old children: effects of acute nighttime sleep restriction, wake time, and daytime napping, Dev. Psychobiol., 54, 412, 10.1002/dev.20599

Griefahn, 2010, The normalization of the cortisol awakening response and of the cortisol shift profile across consecutive night shifts—an experimental study, Psychoneuroendocrinology, 35, 1501, 10.1016/j.psyneuen.2010.05.002

Griefahn, 2011, Cortisol awakening response—are sampling delays of 15minutes acceptable?, Int. J. Psychophysiol., 82, 202, 10.1016/j.ijpsycho.2011.08.005

Gröschl, 2001, Stability of salivary steroids: the influences of storage, food and dental care, Steroids, 66, 737, 10.1016/S0039-128X(01)00111-8

Hajat, 2010, Socioeconomic and race/ethnic differences in daily salivary cortisol profiles: the multi-ethnic study of atherosclerosis, Psychoneuroendocrinology, 35, 932, 10.1016/j.psyneuen.2009.12.009

Harris, 2007, Coffee, stress and cortisol in nursing staff, Psychoneuroendocrinology, 32, 322, 10.1016/j.psyneuen.2007.01.003

Harris, 2010, Cortisol, reaction time test and health among offshore shift workers, Psychoneuroendocrinology, 35, 1339, 10.1016/j.psyneuen.2010.03.006

Hellhammer, 2007, Several daily measurements are necessary to reliably assess the cortisol rise after awakening: state- and trait components, Psychoneuroendocrinology, 32, 80, 10.1016/j.psyneuen.2006.10.005

Hellhammer, 2009, Salivary cortisol as a biomarker in stress research, Psychoneuroendocrinology, 34, 163, 10.1016/j.psyneuen.2008.10.026

Hill, 2008, Exercise and circulating cortisol levels: the intensity threshold effect, J. Endocrinol. Invest., 31, 587, 10.1007/BF03345606

Hruschka, 2005, Estimating between- and within-individual variation in cortisol levels using multilevel models, Psychoneuroendocrinology, 30, 698, 10.1016/j.psyneuen.2005.03.002

Huber, 2006, The cortisol awakening response is blunted in psychotherapy inpatients suffering from depression, Psychoneuroendocrinology, 31, 900, 10.1016/j.psyneuen.2006.03.005

Hucklebridge, 2002, The awakening cortisol response—no evidence for an influence of body posture, Life Sci., 71, 639, 10.1016/S0024-3205(02)01726-5

Huikuri, 1994, Circadian rhythms of frequency domain measures of heart rate variability in healthy subjects and patients with coronary artery disease. Effects of arousal and upright posture, Circulation, 90, 121, 10.1161/01.CIR.90.1.121

Jönsson, 2003, Determination of cortisol in human saliva using liquid chromatography-electrospray tandem mass spectrometry, J. Chromatogr. B., 10.1016/S1570-0232(02)00753-5

Kelly, 2012, Recent developments in home sleep-monitoring devices, ISRN Neurol., 10.5402/2012/768794

Khoury, 2015, Summary cortisol reactivity indicators: interrelations and meaning, Neurobiol. Stress, 2, 34, 10.1016/j.ynstr.2015.04.002

Kirschbaum, 1989, Salivary cortisol in psychobiological research—an overview, Neuropsychobiology, 22, 150, 10.1159/000118611

Kirschbaum, 1994, Salivary cortisol in psychoneuroendocrine research: recent developments and applications, Psychoneuroendocrinology, 19, 313, 10.1016/0306-4530(94)90013-2

Kivlighan, 2004, Quantifying blood leakage into the oral mucosa and its effects on the measurement of cortisol, dehydroepiandrosterone, and testosterone in saliva, Horm. Behav., 46, 39, 10.1016/j.yhbeh.2004.01.006

Kondratova, 2012, The circadian clock and pathology of the ageing brain, Nat. Rev. Neurosci., 13, 325, 10.1038/nrn3208

Kudielka, 2003, Compliance with saliva sampling protocols: electronic monitoring reveals invalid cortisol daytime profiles in noncompliant subjects, Psychosom. Med., 313, 10.1097/01.PSY.0000058374.50240.BF

Kudielka, 2007, Circadian cortisol profiles and psychological self-reports in shift workers with and without recent change in the shift rotation system, Biol. Psychol., 74, 92, 10.1016/j.biopsycho.2006.08.008

Kudielka, 2007, Compliance with ambulatory saliva sampling in the Chicago health, aging, and social relations study and associations with social support, Ann. Behav. Med., 34, 209, 10.1007/BF02872675

Kudielka, 2009, Why do we respond so differently? Reviewing determinants of human salivary cortisol responses to challenge, Psychoneuroendocrinology, 34, 2, 10.1016/j.psyneuen.2008.10.004

Kudielka, 2012, Salivary cortisol in ambulatory assessment-some dos, some don'ts, and some open questions, Psychosom. Med., 74, 418, 10.1097/PSY.0b013e31825434c7

Kudielka, 2003, Awakening cortisol responses are influenced by health status and awakening time but not by menstrual cycle phase, Psychoneuroendocrinology, 28, 35, 10.1016/S0306-4530(02)00008-2

Kudielka, 2010, Human models in acute and chronic stress: assessing determinants of individual hypothalamus-pituitary-adrenal axis activity and reactivity, Stress, 13, 1, 10.3109/10253890902874913

Kumari, 2009, Self-reported sleep duration and sleep disturbance are independently associated with cortisol secretion in the Whitehall II study, J. Clin. Endocrinol. Metab., 94, 4801, 10.1210/jc.2009-0555

Kunz-Ebrecht, 2004, Differences in cortisol awakening response on work days and weekends in women and men from the Whitehall II cohort, Psychoneuroendocrinology, 29, 516, 10.1016/S0306-4530(03)00072-6

Kunz-Ebrecht, 2004, Work stress, socioeconomic status and neuroendocrine activation over the working day, Soc. Sci. Med., 58, 1523, 10.1016/S0277-9536(03)00347-2

Kupper, 2005, Familial influences on basal salivary cortisol in an adult population, Psychoneuroendocrinology, 30, 857, 10.1016/j.psyneuen.2005.04.003

Lasikiewicz, 2008, Exploration of basal diurnal salivary cortisol profiles in middle-aged adults: associations with sleep quality and metabolic parameters, Psychoneuroendocrinology, 33, 143, 10.1016/j.psyneuen.2007.10.013

Law, 2013, State variation in the cortisol awakening response, Stress, 16, 483, 10.3109/10253890.2013.817552

Lichstein, 2006, Actigraphy validation with insomnia, Sleep, 29, 232

Llabre, 2004, Applying latent growth curve modeling to the investigation of individual differences in cardiovascular recovery from stress, Psychosom. Med., 66, 10.1097/01.PSY.0000107886.51781.9C

Lopez-Duran, 2014, Modeling neuroendocrine stress reactivity in salivary cortisol: adjusting for peak latency variability, Stress, 3890, 1

Maina, 2009, Salivary cortisol and psychosocial hazards at work, Am. J. Ind. Med., 52, 251, 10.1002/ajim.20659

Masharani, 2005, Impact of exogenous glucocorticoid use on salivary cortisol measurements among adults with asthma and rhinitis, Psychoneuroendocrinology, 30, 744, 10.1016/j.psyneuen.2005.03.003

Meltzer, 2015, Comparison of a commercial accelerometer with polysomnography and actigraphy in children and adolescents, Sleep, 38, 1323, 10.5665/sleep.4918

Menet, 2011, When brain clocks lose track of time: cause or consequence of neuropsychiatric disorders, Curr. Opin. Neurobiol., 21, 849, 10.1016/j.conb.2011.06.008

Miller, 2013, Transformation techniques for cross-sectional and longitudinal endocrine data: application to salivary cortisol concentrations, Psychoneuroendocrinology, 38, 941, 10.1016/j.psyneuen.2012.09.013

Miller, 2013, Classification criteria for distinguishing cortisol responders from nonresponders to psychosocial stress: evaluation of salivary cortisol pulse detection in panel designs, Psychosom. Med., 40

Miller, 2013, Comparison of salivary cortisol as measured by different immunoassays and tandem mass spectrometry, Psychoneuroendocrinology, 38, 50, 10.1016/j.psyneuen.2012.04.019

Nader, 2010, Interactions of the circadian CLOCK system and the HPA axis, Trends Endocrinol. Metab., 21, 277, 10.1016/j.tem.2009.12.011

Nicolson, 2000, Salivary cortisol patterns in vital exhaustion, J. Psychosom. Res., 49, 335, 10.1016/S0022-3999(00)00166-5

Okun, 2010, What constitutes too long of a delay? Determining the cortisol awakening response (CAR) using self-report and PSG-assessed wake time, Psychoneuroendocrinology, 35, 460, 10.1016/j.psyneuen.2009.08.017

Oskis, 2009, Diurnal patterns of salivary cortisol across the adolescent period in healthy females, Psychoneuroendocrinology, 34, 307, 10.1016/j.psyneuen.2008.09.009

Perogamvros, 2010, Salivary cortisone is a potential biomarker for serum free cortisol, J. Clin. Endocrinol. Metab., 95, 4951, 10.1210/jc.2010-1215

Polk, 2005, State and trait affect as predictors of salivary cortisol in healthy adults, Psychoneuroendocrinology, 30, 261, 10.1016/j.psyneuen.2004.08.004

Pruessner, 1997, Free cortisol levels after awakening: a reliable biological marker for the assessment of adrenocortical activity, Life Sci., 61, 2539, 10.1016/S0024-3205(97)01008-4

Pruessner, 2003, Two formulas for computation of the area under the curve represent measures of total hormone concentration versus time-dependent change, Psychoneuroendocrinology, 28, 916, 10.1016/S0306-4530(02)00108-7

Raudenbush, 2002

Roa, 2013, The cortisol awakening response is blunted in patients with active Cushing’s disease, Eur. J. Endocrinol., 168, 657, 10.1530/EJE-12-0982

Roberts, 2004, Salivary cortisol response to awakening in chronic fatigue syndrome, Br. J. Psychiatry, 184, 136, 10.1192/bjp.184.2.136

Rohleder, 2007, Effects of nutrition on neuro-endocrine stress responses, Curr. Opin. Clin. Nutr. Metab. Care, 10, 504, 10.1097/MCO.0b013e3281e38808

Rosmond, 2000, Food-induced cortisol secretion in relation to anthropometric, metabolic and haemodynamic variables in men, Int. J. Obes. Relat. Metab. Disord., 24, 416, 10.1038/sj.ijo.0801173

Schafer, 2002, Missing data: our view of the state of the art, Psychol. Methods, 7, 147, 10.1037/1082-989X.7.2.147

Scheer, 1999, Light affects morning salivary cortisol in humans, J. Clin. Endocrinol. Metab., 84, 3395, 10.1210/jcem.84.9.6102

Schlotz, 2011, Ambulatory psychoneuroendocrinology: assessing salivary cortisol and other hormones in daily life, 193

Schlotz, 2004, Perceived work overload and chronic worrying predict weekend-weekday differences in the cortisol awakening response, Psychosom. Med., 66, 207, 10.1097/01.psy.0000116715.78238.56

Schlotz, 2011, Individual differences in the cortisol response to stress in young healthy men: testing the roles of perceived stress reactivity and threat appraisal using multiphase latent growth curve modeling, Biol. Psychol., 87, 257, 10.1016/j.biopsycho.2011.03.005

Schmidt-Reinwald, 1999, The cortisol response to awakening in relation to different challenge tests and a 12h cortisol rhythm, Life Sci., 64, 1653, 10.1016/S0024-3205(99)00103-4

Schulz, 1994, Biological uniqueness and the definition of normality. Part 2–the endocrine ‘fingerprint’ of healthy adults, Med. Hypotheses, 42, 63, 10.1016/0306-9877(94)90038-8

Smith, 2014, Noisy spit: parental noncompliance with child salivary cortisol sampling, Dev. Psychobiol., 56, 647, 10.1002/dev.21133

Smyth, 2013, Delays of 5–15min between awakening and the start of saliva sampling matter in assessment of the cortisol awakening response, Psychoneuroendocrinology, 38, 1476, 10.1016/j.psyneuen.2012.12.013

Smyth, 2015, Detailed time course of the cortisol awakening response in healthy participants, Psychoneuroendocrinology, 10.1016/j.psyneuen.2015.08.011

Steptoe, 2004, Central adiposity and cortisol responses to waking in middle-aged men and women, Int. J. Obes. Relat. Metab. Disord., 28, 1168, 10.1038/sj.ijo.0802715

Stalder, 2009, Use of a single case study design to examine state variation in the cortisol awakening response: Relationship with time of awakening, Psychoneuroendocrinology, 34, 607, 10.1016/j.psyneuen.2008.10.023

Stalder, 2010, Associations between psychosocial state variables and the cortisol awakening response in a single case study, Psychoneuroendocrinology, 35, 209, 10.1016/j.psyneuen.2009.06.006

Stalder, 2010, State associations with the cortisol awakening response in healthy females, Psychoneuroendocrinology, 35, 1245, 10.1016/j.psyneuen.2010.02.014

Stalder, 2011, Associations between the cortisol awakening response and heart rate variability, Psychoneuroendocrinology, 36, 454, 10.1016/j.psyneuen.2010.07.020

Stalder, 2013, The cortisol awakening response in infants: ontogeny and associations with development-related variables, Psychoneuroendocrinology, 38, 552, 10.1016/j.psyneuen.2012.07.015

Steptoe, 2006, Smoking, cortisol and nicotine, Int. J. Psychophysiol., 59, 228, 10.1016/j.ijpsycho.2005.10.011

Tassi, 2000, Sleep inertia, Sleep Med. Rev., 4, 341, 10.1053/smrv.2000.0098

Therrien, 2007, Awakening cortisol response in lean, obese, and reduced obese individuals: effect of gender and fat distribution, Obesity, 15, 377, 10.1038/oby.2007.509

Thorn, 2004, The effect of dawn simulation on the cortisol response to awakening in healthy participants, Psychoneuroendocrinology, 29, 925, 10.1016/j.psyneuen.2003.08.005

Thorn, 2011, Seasonal differences in the diurnal pattern of cortisol secretion in healthy participants and those with self-assessed seasonal affective disorder, Psychoneuroendocrinology, 36, 816, 10.1016/j.psyneuen.2010.11.003

Thorn, 2006, Suspected non-adherence and weekend versus week day differences in the awakening cortisol response, Psychoneuroendocrinology, 31, 1009, 10.1016/j.psyneuen.2006.05.012

Trinder, 2001, Cardiac and respiratory activity at arousal from sleep under controlled ventilation conditions, J. Appl. Physiol., 90, 1455, 10.1152/jappl.2001.90.4.1455

Trinder, 2003, On the nature of cardiovascular activation at an arousal from sleep, Sleep, 26, 543

Van de Water, 2011, Objective measurements of sleep for non-laboratory settings as alternatives to polysomnography—a systematic review, J. Sleep Res., 20, 183, 10.1111/j.1365-2869.2009.00814.x

Veldhuis, 1989, Amplitude modulation of a burstlike mode of cortisol secretion subserves the circadian glucocorticoid rhythm, Am. J. Physiol., 257, E6

Vreeburg, 2009, Associations between sociodemographic, sampling and health factors and various salivary cortisol indicators in a large sample without psychopathology, Psychoneuroendocrinology, 34, 1109, 10.1016/j.psyneuen.2009.04.024

Weitzman, 1971, Twenty-four hour pattern of episodic secretion of cortisol in normal subjects, J. Clin. Endocrinol. Metab., 33, 14, 10.1210/jcem-33-1-14

Wetherell, 2015, The effects of an anticipated challenge on diurnal cortisol secretion, Stress, 18, 42, 10.3109/10253890.2014.993967

Whembolua, 2006, Bacteria in the oral mucosa and its effects on the measurement of cortisol, dehydroepiandrosterone, and testosterone in saliva, Horm. Behav., 49, 478, 10.1016/j.yhbeh.2005.10.005

Wilder, 1962, Basimetric approach (law of initial value) to biological rhythms, Ann. N. Y. Acad. Sci., 98, 1211, 10.1111/j.1749-6632.1962.tb30629.x

Wilhelm, 2007, Is the cortisol awakening rise a response to awakening?, Psychoneuroendocrinology, 32, 358, 10.1016/j.psyneuen.2007.01.008

Williams, 2005, The impact of time of waking and concurrent subjective stress on the cortisol response to awakening, Psychoneuroendocrinology, 30, 139, 10.1016/j.psyneuen.2004.06.006

Willoughby, 2007, A structural equation modeling approach for the analysis of cortisol data collected using pre–post–post designs, Struct. Equ. Model. A Multidiscip. J., 14, 125

Wolf, 2005, No morning cortisol response in patients with severe global amnesia, Psychoneuroendocrinology, 30, 101, 10.1016/j.psyneuen.2004.05.001

Wolfram, 2011, The cortisol awakening response (CAR) across the female menstrual cycle, Psychoneuroendocrinology, 36, 905, 10.1016/j.psyneuen.2010.12.006

Wright, 2005, Subjective socioeconomic position, gender and cortisol responses to waking in an elderly population, Psychoneuroendocrinology, 30, 582, 10.1016/j.psyneuen.2005.01.007

Wüst, 2000, Genetic factors, perceived chronic stress, and the free cortisol response to awakening, Psychoneuroendocrinology, 25, 707, 10.1016/S0306-4530(00)00021-4

Wüst, 2000, The cortisol awakening response—normal values and confounds, Noise Health, 2, 79

Zeiders, 2011, Reciprocal relations between objectively measured sleep patterns and diurnal cortisol rhythms in late adolescence, J. Adolesc. Heal., 48, 566, 10.1016/j.jadohealth.2010.08.012