A pilot intervention management program for students of secondary education

Φωτογραφία από την Daria Shevtsova στο Pexels


Puberty constitutes a crucial period which foresees future health problems but is also open to interventions and changes. It is characterized by physical and psychosocial changes, which are affected by genetic, hormonal and environmental factors (Chulani VL, 2014).

Adolescence is defined as “the period in which secondary sexual characteristics are formed and reproductive capacity is developed” (Dunkel and Quinton, 2014). The beginning of adolescence depends on the hypothalamus-pituitary-gonadal axis (HPG) (Ojeda and Lomniczi, 2014).

During puberty, the increased concentration of sex steroids stimulates the activation of the GH (Growth Hormone) axis via the increased secretion of growth hormone; also, insulin levels are increased (Sizonenko and Paunier, 1975).

Neuroendocrinological control of puberty involves many genes, which dispose multidimensional functions. The responsible genes for puberty control are organized into networks which are necessary for the generation of reproductive function and genes which contribute to the beginning of puberty (Ojeda et al., 2010a).

Furthermore, there are not only observed gonadal changes, but also cerebellar. The maturation periods of the brain regions vary by age. It is reported for human sample that subcortical structures which are associated with thymic and reward system, note a faster maturation compared to the development of cognitive functions; this chronical differentiation is enhanced during the period of puberty (Mills et al., 2014).

From childhood to adolescence is observed an increase in the sense of demand and in the adoption of risky behaviors, whose dynamic is declined strongly in adulthood (Steinberg et al., 2008, Casey et al., 2008). However, the pre-frontal cortex, which is responsible for controlling impulsions and for decision-making, is developing continuously (Casey et al., 2008).

An important feature of the transition of childhood into adolescence is the change of appearance. The development of secondary sexual characteristics constitutes a milestone of adolescence (Gasser et al., 2013). The first exterior signs of puberty are observed in girls by breast growth and in boys by testicular enlargement (Marshall and M Tanner, 1969; Marshall and Tanner, 1970).

Over the years, from the mid-19th century to the middle of the 20th century, it has been observed that the age which was marking puberty, was gradually decreased both in boys and girls especially in industrial areas due to socio-economic stability and in expansion the improvement of hygiene and nutrition; the last two characteristics of society have greatly contributed to the proper development of children. The first signs of puberty appear on average on 10 for girls and 12 on boys (Sørensen et al., 2010, Sorensen et al., 2012, Dunkel and Quinton, 2014). However, the normal age of puberty is observed from 8 to13 for girls and 9 to14 for boys.

Based on the Sexually Maturity Ratings or otherwise called “Tanner’s Stages”, the stages of maturation of secondary sexual characteristics from pre-adolescence to adulthood are indicated. Stages should be assessed separately, for instance, a stage for pubic hair and one for the chest development for women, a stage for pubic hair and one for genitals for men (Tanner, 1962).

In contrast to the SMR, some studies do not classify pubic hair as a mark of puberty as it may be the result of adrenal maturation (Dunkel and Quinton, 2014).

The body changes during adolescence. According to contemporary data, body constitutes a basic element for the individual (Lu et al., 2015). Appearance highly influences the individual’s perception about his/her image and if there is a hidden psychopathology, it is highly possible to develop psychological and physical problems such as eating disorder (Peat et al., 2008), depression (Stice et al., 2000) and psychological stress (Johnson and Wardle, 2005).

The exploration of personal identity comes to the foreground (Collier et al., 2013, Tornello et al., 2014). The need of searching for their sexual identity originates from the transformation of their physical form and the maturation of reproductive system, which lead to the enhancement of sexual mood (Welon, 1982).

Except for internal struggles which are hidden and cultivated due to the adolescent’s development, the interpersonal relationships (siblings, peers, classmates) (McHale, 2005), the systems/environments which surround the individual, such as family (Foxman et al., 1989) and school (Judi Kidger, May 2012), play an important role.

The adolescents-students have to face daily demands and obligations; their judgment, perception and skills reflect their coping skills. From one hand, certain individuals perceive these challenges as constructive stressful events which enhance eustress (Chrousos, 2009). However, each one disposes different perception about stress; other individuals think that stress functions like a negative force and they perceive stressful situations as threats; then they “adopt” distress, namely lack of coping skills oppose to stress (Ridner, 2004) (Chrousos, 2009).

Miscellaneous stressors can affect students’ psychosynthesis and their academic performance. The mood and the socio-economic level are related to subjective well-being and constitute key pillars by influencing academic image (Manstead, 2018). It has been proven that even unhealthy nutrition in the school and family environment deteriorate academic performance (Correa-Burrows et al., 2015).

Over the last few decades, and especially in recent years, there has been a tendency to penetrate stress management techniques into education, particularly the “mindfulness” technique, which focuses on the present moment (Kuyken et al., 2018, Bostic et al., 2015).

Achieving a meaningful and fruitful intervention which will focus on improving academic achievement, self-esteem and student happiness, will be accomplished through an innovative technique, the Pythagorean Self-Awareness. This technique aims to the holistical improvement of person’s life. It teaches the sharpening of critical thinking, the objective assessment of actions, and sets new goals for self-improvement.


1st Hypothesis: According to the structure of this innovative technique, we posit that it will be positively evaluated and it will be established in school context.

2nd Hypothesis: According to bibliography stress can affect academic performance. As a result, if stress would be reduced, academic performance would be ameliorated.

3rd Hypothesis: Pythagorean Self-Awareness Technique aims to enhance self-esteem, health locus of control, positive emotions, well-being, level of satisfaction; to ameliorate daily routine, quality of sleep, heart rate during stressful events, academic performance, to change perception about stressors and to reduce psychological distress and anxiety.

Material and Methods

The sample of the study was 31 individuals (N=31). According to Table 1 the sample consisted of 18 girls (49.1%). During the follow-up was observed 1 drop out (N=30). The age average is 12 years old. The most of them have siblings and their parents are married. All sample derives from a private school of Attica, North suburbs. The research was addressed only to 1st Gymnasium.

The necessary criterion for admission to the survey was that the participants should be students, both female and male, of secondary education, in the first grade of Gymnasium. Necessary condition was the written and oral knowledge of Greek language and permanent residency in Attica. The integration into the research was completed by giving the consent form signed by students’ guardian to the researcher.

The exclusion criteria were based on individual’s health; the study was referred to a healthy population. If a teen was taking medication for mental diseases, he/she was not eligible to participate into the survey. Furthermore, applicants taking chronic systemic corticosteroid therapy would not be able to take part. The participants who would not complete the required number of meetings or changed school would not be included in the survey.

Self-report questionnaires were given before and after intervention. There was a mathematic trial and measurement by biofeedback the same periods. During follow-up measuring self-report questionnaires were repeated. All grades of semesters and final exams were taken into consideration.

The used questionnaires were sociodemographic, Health Indicators – Medical Background – Routine – Quality and Lifestyle ». It consists 42 items. The daily routine is estimated by 20 questions.

There are also sociodemographic and medical characteristics via 33 questions, 8 items measuring satisfaction and 4 related to stress. Medical School of Athens has the right of this scale. Daily Hassles Microsystem Scale derives from Daily Hassles Questionnaire of Rowlison and Felner (1988) (Rowlison and Felner, 1988) which is modified form of Hassles Scale of Kanner (1981) (Kanner et al., 1981). Items are referred to the family, peers, and perceived discomforts arising from residence. The items are 28. Answers are closed-ended, yes or no, whether the event has taken place in the last month; if the answer is positive, the respondent completes a 4 scale which reflects the tendency (Kanner et al., 1981).

Moreover, Beck Anxiety Inventory investigates the bothering rate of 21 reported symptoms on a scale from 0 to 3, where 0 = none, 1 = low (not bothered much), 2 = moderate (it was very unpleasant but could to endure it), 3 = strong (I could hardly endure) (Steer et al., 1993).

Adolescent Stress Questionnaire examines 58 subjects, 10 dimensions that can cause stress within 12 months: i) family stress, ii) school performance, iii) school attendance, iv) love relationships, v) peer pressure , vi) interaction with the teacher, vii) uncertainty of the future, viii) school / leisure time, ix) financial pressure, and x) emerging adult obligations (Byrne et al., 2007). The scale has been adapted to the Greek language with satisfactory cross-term validity and seems to bring high internal credibility (Darviri C, 2014).

Culture-free Self-esteem Inventory is a self-referencing questionnaire, which contains 30 items that measure the personal perception of self. It is the short version of CFSEI-A (60 questions). Scale proposals / questions evaluate their attitudes, their values which are associated with teenagers’ intelligence, school, and academic capabilities. The studied elements are divided into two groups, which reveal high and low self-esteem. The questions are closed-ended, yes or no. It has 5 sub-scales, General Self-esteem, Academic Self-esteem, Parent Self-esteem, Social Self-esteem, and Scale of Lying (J., 2002, Brunsman, 2003, Community-University Partnership for the Study of Children, 2011).

Oxford Happiness Scale refers to the happiness experienced by every person on various sides. It is a multidimensional questionnaire. It contains 29 elements, presented in four factors, satisfaction with life, energy, positive emotion and sociability (Peter Hills, 2002). Multidimensional Health Locus of Control (MHLC) is derived from the Health Locus of Control scale (Panagiotopoulos et al., 2015, Wallston et al., 1976). It reflects three dimensions that need to be considered: the internal control center, the important others and the fate (Wallston et al., 1978).

PANAS (Positive and Negative Affect Schedule) constitutes a scale which consists 20 adjectives, 10 positive and 10 negative (Watson et al., 1988). Pittsburgh Hellenic Sleep Quality Index (GR-PSQI) is a scale that calculates the quality of sleep. It differentiates the “poor” from “good” sleep quality by measuring 7 different elements: subjective sleep quality, sleep inactivity, sleep duration, normal sleep performance, sleep disorders, sleep medication and daytime dysfunction in the last month. The 6 questions (Buysse et al., 1989). It has high reliability and validity. It is adapted in Greek (Kotronoulas et al., 2011). Last, Rosenberg Self-Esteem Scale estimates the value of self through 10 elements with positive and negative meaning (Rosenberg, 1979).

The intervention lasted two months. During the meetings, participants learned Pythagorean Self-Awareness Technique and Diaphragmatic breathing. The first technique was based in twelve virtues, charity and spirituality, temperance, cleanliness, decent behavior, courage, contribution to the general good, respect to laws, industriousness and activity, truthfulness, collaboration, order and accuracy and justice, which were teached via interactive way. The participants had to complete a recording diary of doing the technique. Based on this diary the participants were separated in three compliance groups, high (4-7 times), low (3-1 times) and zero.

The data are summarized in the form of frequency tables based on descriptive statistical analysis. Categorical variables are presented with frequencies and percentages. Continuous variables are presented with descriptive statistics (number of patients, mean and median, standard deviation, range). The statistical analysis is completed by SPSS v22.0.


As mentioned above, the sample of the survey is N = 31 (see Table 1). Participants are divided into three subgroups, high (N = 19, 61.3%), low (N = 8, 25.8%) and zero compliance (N = 4, 12.9%).

According to Table 2 the highest average values belonged to the group with no obedience. A larger difference in the mean values before and after intervention was observed in the low obedience group, as the high obedience group had a better response to the mathematical test from the outset. Although there was no statistically significant relationship between the initial and final measurements of Heart rate during stress scenes, its mean decreased from 87.35 to 85.84 for the high obedience group. The low-compliance group showed a slight improvement, while the group of low obedience was deteriorated.

According to Table 3, higher rankings tended to be of the high compliance group. It was observed that they had the highest average values in all semesters and their performance in the final writing examinations was better than the other groups. Correspondingly is observed for academic performance in the 1st and 2nd Gymnasium. The lower scores in both semesters and promotional tests were brought by the group that did not practice at all. The low compliance group improved semesters’ grades and final examinations.

Table 4 presents the results of psychological measurements. The scale of the daily routine showed little improvement for the teams involved in the technique, while the scoring of the team of zero compliance to the technique was diminished, ie from 51.5 total scoring after the intervention was reduced to 45.25.

Satisfaction levels tended to be higher in follow-up, but after the intervention, the low-compliance group experienced a slight improvement. However, the scoring of the high compliance group had the highest prices compared to the other groups in all measurements.

Typical improvement was observed for the high compliance group in sleep scale; the initial measurement was 3.68 and after the intervention was decreased to 0.58.

Small improvements were observed in all subscales of Adolescent Stress Questionnaire for high and low compliance groups in the PST. The group of low compliance failed to note the same results, on the contrary some prices got worse.

On the scale of positive and negative emotions (PANAS) there was a positive decrease in negative emotions and an increase in positive for the three groups. Greater increase in positive emotions was recorded by the low compliance group, from 32.38 to 35.25.

The MHLC scale indicated that the highest averages were scored in internal control sub-scale, followed by the external control sub-scale (important others), and then luck. Small differences were noted, but the average of the internal control remains on the first place for the three groups.

The subscales of the OHS questionnaire showed small differences before and after the intervention. A characteristic difference was observed in the follow-up measurement as the values of all groups were improved.

In Beck Anxiety Questionnaire, a marked positive decrease was observed in the low compliance group from 16 to 11.63, but the other groups noted a decrease. A significant increase was recorded in the follow-up values in all groups.


Pythagorean Self-Awareness Technique constitutes an innovative technique, and there are not yet plentiful researches to compare with these findings, but so far it has tended to make a significant contribution to improve stress management and quality of life (Darviri, 2016, Callianta Maria-Despina, 2017, Bitchava Ioanna C., 2017, Foteini Chatzikonstantinou, 2018).

The participants in the survey and especially those who belonged in the high compliance group succeed to improve both their academic performance and the mathematical trial. The semester grades were improved and the high compliance group disposed the highest average. In addition, the academic self-esteem of the high obedience group has increased. Researches have shown that reinforcement of self and self-awareness contribute positively to academic achievement and to the general well-being of the individual (Widlund, 2018, Green et al., 2012). Pythagorean Self-Awareness Technique contributes to enhance the pre-announced features.

Moreover, heart rate was improved during stressful scenes. We can not prove linear causality, although it was observed that Pythagorean Self-Awareness Technique might affect the sympathetic nervous system, from the moment it has been proven that stress can increase heart rate and respiratory system; in general stress management techniques affect the nervous system. (Schubert et al. – 2009, Bluth et al. – 2017)

A strong change was also observed in sleeping rates as there was a significant improvement. It constitutes another proof that the technique can affect the parasympathetic nervous system and sleep; as stress affects the quality of sleep (Drake et al., 2014). According to studies on adolescent sleep have been carried out with different interventional techniques, such as Cognitive Behavior Therapy, but not with this kind of technique. (Brand and Kirov – 2011, Gradisar et al. – 2011)

The daily routine was ameliorated for the high compliance group, although the intensity of daily hassles was increased. According to previous surveys based on Pythagorean Self-Awareness, the improvement of the quality of everyday life has been observed (Bitchava Ioanna C., 2017, Schubert et al., 2009).

Changes were observed in psychological well-being and stress scales. Certain variables have been improved and others remained stable or may have been mildly declined. The low compliance group was tending to improve most variables. In general, stress influences not only the self and the well-being of individual, but also the surrounding “systems” may be responsible for the development of a psychopathology (Martin Rod et al., 1993, Woody et al. 2018).

Important observation was also the reduction of negative emotions and the enhancement of positive ones. Although puberty is a period of hormonal changes that affect the psychology of the individual, the technique proved that it can contribute positively to the enhancement of the individual (Lougheed et al., 2016).

Learning the adolescents to improve their daily routine and generally to adopt a healthy lifestyle that includes proper nutrition, good sleep quality, exercise, and abstain from continuous employment with electronics, their performance and image for themselves will be in the desired levels; as a result, it will be ensured a better and healthier future away from the modern scourge of society (panic attacks, anxiety disorders, depression, metabolic syndrome).


The observed limitations were the following: 1) the research was a pilot study because the number of participants and there was heterogeneity since the number of boys and girls was unequal in the groups of obedience, 2) the questionnaires were self-report and therefore there was the element, 3) the participants were in groups of 20 students. Also 4) the research was non-blind and 5) the duration of the intervention program was short.


  • CHULANI VL, G. L. 2014. Adolescent growth and development. Primary care. 41(3):465-87.
  • DUNKEL, L. & QUINTON, R. 2014. Transition in endocrinology: induction of puberty. Eur J Endocrinol, 170, R229-39.
  • OJEDA, S. R. & LOMNICZI, A. 2014. Puberty in 2013: Unravelling the mystery of puberty. Nat Rev Endocrinol, 10, 67-9.
  • SIZONENKO, P. C. & PAUNIER, L. 1975. Hormonal changes in puberty III: Correlation of plasma dehydroepiandrosterone, testosterone, FSH, and LH with stages of puberty and bone age in normal boys and girls and in patients with Addison’s disease or hypogonadism or with premature or late adrenarche. J Clin Endocrinol Metab, 41, 894-904.
  • OJEDA, S. R., LOMNICZI, A., LOCHE, A., MATAGNE, V., KAIDAR, G., SANDAU, U. S. & DISSEN, G. A. 2010a. The Transcriptional Control of Female Puberty. Brain research, 1364, 164-174.
  • OJEDA, S. R., LOMNICZI, A. & SANDAU, U. 2010b. Contribution of Glial-Neuronal Interac-tions to the Neuroendocrine Control of Female Puberty. The European journal of neuro-science, 32, 2003-2010.
  • MILLS, K. L., GODDINGS, A. L., CLASEN, L. S., GIEDD, J. N. & BLAKEMORE, S. J. 2014. The developmental mismatch in structural brain maturation during adolescence. Dev Neurosci, 36, 147-60.
  • STEINBERG, L., ALBERT, D., CAUFFMAN, E., BANICH, M., GRAHAM, S. & WOOLARD, J. 2008. Age differences in sensation seeking and impulsivity as indexed by behavior and self-report: evidence for a dual systems model. Dev Psychol, 44, 1764-78.
  • CASEY, B. J., GETZ, S. & GALVAN, A. 2008. The adolescent brain. Dev Rev, 28, 62-77.
  • GASSER, T., MOLINARI, L. & LARGO, R. 2013. A comparison of pubertal maturity and growth. Ann Hum Biol, 40, 341-7.
  • MARSHALL, W. A. & M TANNER, J. 1969. Marshall WA, Tanner JM. Variations in pattern of pubertal changes in girls. Arch Dis Child 44, 291-303.
  • MARSHALL, W. A. & TANNER, J. M. 1970. Variations in the Pattern of Pubertal Changes in Boys. Archives of Disease in Childhood, 45, 13-23.
  • SØRENSEN, K., AKSGLAEDE, L., PETERSEN, J. H. & JUUL, A. 2010. Recent Changes in Pubertal Timing in Healthy Danish Boys: Associations with Body Mass Index. The Jour-nal of Clinical Endocrinology & Metabolism, 95, 263-270.
  • SORENSEN, K., MOURITSEN, A., AKSGLAEDE, L., HAGEN, C. P., MOGENSEN, S. S. & JUUL, A. 2012. Recent secular trends in pubertal timing: implications for evaluation and diagnosis of precocious puberty. Horm Res Paediatr, 77, 137-45.
  • DUNKEL, L. & QUINTON, R. 2014. Transition in endocrinology: induction of puberty. Eur J Endocrinol, 170, R229-39.
  • TANNER, J. M. 1962. Growth at adolescence, Oxford, Blackwell Scientific Publications.
  • LU, A., HONG, X., YU, Y., LING, H., TIAN, H., YU, Z. & CHANG, L. 2015. Perceived physical appearance and life satisfaction: a moderated mediation model of self-esteem and life experience of deaf and hearing adolescents. J Adolesc, 39, 1-9.
  • PEAT, C. M., PEYERL, N. L. & MUEHLENKAMP, J. J. 2008. Body image and eating disorders in older adults: a review. J Gen Psychol, 135, 343-58.
  • STICE, E., HAYWARD, C., CAMERON, R. P., KILLEN, J. D. & TAYLOR, C. B. 2000. Body-image and eating disturbances predict onset of depression among female adolescents: a longitudinal study. J Abnorm Psychol, 109, 438-44.
  • JOHNSON, F. & WARDLE, J. 2005. Dietary restraint, body dissatisfaction, and psychological distress: a prospective analysis. J Abnorm Psychol, 114, 119-25.
  • COLLIER, K. L., VAN BEUSEKOM, G., BOS, H. M. W. & SANDFORT, T. G. M. 2013. Sexual Orientation and Gender Identity/Expression Related Peer Victimization in Adolescence: A Systematic Review of Associated Psychosocial and Health Outcomes. Journal of sex research, 50, 299-317.
  • TORNELLO, S. L., RISKIND, R. G. & PATTERSON, C. J. 2014. Sexual orientation and sexual and reproductive health among adolescent young women in the United States. J Adolescence Health, 54, 160-8.
  • WELON, T. B. Z. 1982. Growth data as indicators of social inequalities: The case of Poland. American Journal of Physical Anthropology, 153-167.
  • MCHALE, K. A. U. S. M. T. S. D. W. D. J. D. S. M. 2005. Relational Aggression in Adolescents’ Sibling Relationships: Links to Sibling and Parent‐Adolescent Relationship Quality. Interdisciplinary Journal of Applied Family Science, 4.
  • FOXMAN, E. R., TANSUHAJ, P. S. & EKSTROM, K. M. 1989. Adolescents’ influence in family purchase decisions: A socialization perspective. Journal of Business Research, 18, 159-172.
  • JUDI KIDGER, R. A., JENNY DONOVAN, DAVID GUNNELL May 2012. The Effect of the School Environment on the Emotional Health of Adolescents: A Systematic Review. Pediatrics, 129.
  • CHROUSOS, G. P. 2009. Stress and disorders of the stress system. Nat Rev Endocrinol, 5, 374-81.
  • RIDNER, S. H. 2004. Psychological distress: concept analysis. J Adv Nurs, 45, 536-45.
  • MANSTEAD, A. S. R. 2018. The psychology of social class: How socioeconomic status impacts thought, feelings, and behaviour. The British journal of social psychology, 57, 267-291.
  • CORREA-BURROWS, P., BURROWS, R., ORELLANA, Y. & IVANOVIC, D. 2015. The relationship between unhealthy snacking at school and academic outcomes: a population study in Chilean schoolchildren. Public Health Nutr, 18, 2022-30.
  • BOSTIC, J. Q., NEVAREZ, M. D., POTTER, M. P., PRINCE, J. B., BENNINGFIELD, M. M. & AGUIRRE, B. A. 2015. Being Present at School. Child and Adolescent Psychiatric Clinics, 24, 245-259.
  • KUYKEN, W., WEARE, K., UKOUMUNNE, O. C., VICARY, R., MOTTON, N., BUR-NETT, R., CULLEN, C., HENNELLY, S. & HUPPERT, F. 2018. Effectiveness of the Mindfulness in Schools Programme: non-randomised controlled feasibility study. British Journal of Psychiatry, 203, 126-131.
  • ROWLISON, R. T. & FELNER, R. D. 1988. Major life events, hassles, and adaptation in adolescence: confounding in the conceptualization and measurement of life stress and adjustment revisited. J Pers Soc Psychol, 55, 432-44.
  • KANNER, A. D., COYNE, J. C., SCHAEFER, C. & LAZARUS, R. S. 1981. Comparison of two modes of stress measurement: daily hassles and uplifts versus major life events. J Behav Med, 4, 1-39.
  • STEER, R. A., RANIERI, W. F., BECK, A. T. & CLARK, D. A. 1993. Further evidence for the validity of the beck anxiety inventory with psychiatric outpatients. Journal of Anxiety Disorders, 7, 195-205.
  • DARVIRI C, L. P., CHATZIOANNIDOU P, GNARDELLIS C, KRANIOTOU C, TIGANI X, ET AL. 2014. Adolescent Stress Questionnaire: reliability and validity of the Greek version and its description in a sample of high school (lyceum) students. Journal of adolescence, 37, 1373-7.
  • BRUNSMAN, B. A. 2003. Review of the Culture-Free Self-Esteem Inventories, third edition.
  • COMMUNITY-UNIVERSITY PARTNERSHIP FOR THE STUDY OF CHILDREN, Y., AND FAMILIES 2011. Review of the Culture-Free Self-Esteem Inventories, Third Edition (CFSEI-3), Edmonton, Alberta, Canada
  • PETER HILLS, M. A. 2002. The Oxford Happiness Questionnaire: a compact scale for the measurement of psychological well-being. Personality and Individual Differences 33, 1073-1082.
  • PANAGIOTOPOULOS, G., GALANAKIS, M., VARVOGLI, L., CHROUSOS, G. & DARVIRI, C. 2015. Validation of the Greek version of Mini Tinnitus Questionnaire as a Brief Screening Test for Assessment of Tinnitus-related Distress: our experience in 301 adult patients. Clin Otolaryngol, 40, 363-9.
  • WALLSTON, B. S., WALLSTON, K. A., KAPLAN, G. D. & MAIDES, S. A. 1976. Development and validation of the health locus of control (HLC) scale. J Consult Clin Psychol, 44, 580-5.
  • WALLSTON, K. A., WALLSTON, B. S. & DEVELLIS, R. 1978. Development of the Multi-dimensional Health Locus of Control (MHLC) Scales. Health Educ Monogr, 6, 160-70.
  • WATSON, D., CLARK, L. A. & TELLEGEN, A. 1988. Development and validation of brief measures of positive and negative affect: the PANAS scales. J Pers Soc Psychol, 54, 1063-70.
  • BUYSSE, D. J., REYNOLDS, C. F., MONK, T. H., BERMAN, S. R. & KUPFER, D. J. 1989. The Pittsburgh sleep quality index: A new instrument for psychiatric practice and re-search. Psychiatry Research, 28, 193-213.
  • KOTRONOULAS, G. C., PAPADOPOULOU, C. N., PAPAPETROU, A. & PATIRAKI, E. 2011. Psychometric evaluation and feasibility of the Greek Pittsburgh Sleep Quality Index (GR-PSQI) in patients with cancer receiving chemotherapy. Support Care Cancer, 19, 1831-40.
  • ROSENBERG, M. 1979. Conceiving the Self., New York.
  • WIDLUND, A. T., HETA & KORHONEN, JOHAN. (2018) 2018. Academic Well-Being, Mathematics Performance, and Educational Aspirations in Lower Secondary Education: Changes Within a School Year. Frontiers in Psychology.
  • GREEN, J., LIEM, G. A., MARTIN, A. J., COLMAR, S., MARSH, H. W. & MCINERNEY, D. 2012. Academic motivation, self-concept, engagement, and performance in high school: key processes from a longitudinal perspective. J Adolesc, 35, 1111-22.
  • SCHUBERT, C., LAMBERTZ, M., NELESEN, R. A., BARDWELL, W., CHOI, J. B. & DIMSDALE, J. E. 2009. Effects of stress on heart rate complexity–a comparison be-tween short-term and chronic stress. Biological psychology, 80, 325-332.
  • BLUTH, K., ROBERSON, P. N. E. & GIRDLER, S. S. 2017. Adolescent Sex Differences in Response to a Mindfulness Intervention: A Call for Research. Journal of child and family studies, 26, 1900-1914.
  • DRAKE, C. L., PILLAI, V. & ROTH, T. 2014. Stress and sleep reactivity: a prospective investigation of the stress-diathesis model of insomnia. Sleep, 37, 1295-1304.
  • BRAND, S. & KIROV, R. 2011. Sleep and its importance in adolescence and in common adolescent somatic and psychiatric conditions. International journal of general medicine, 4, 425-442.
  • GRADISAR, M., DOHNT, H., GARDNER, G., PAINE, S., STARKEY, K., MENNE, A., SLATER, A., WRIGHT, H., HUDSON, J. L., WEAVER, E. & TRENOWDEN, S. 2011. A randomized controlled trial of cognitive-behavior therapy plus bright light therapy for adolescent delayed sleep phase disorder. Sleep, 34, 1671-1680.
  • BITCHAVA IOANNA C., P. A.-M. P., CHROUSOS GEORGE P., ARTEMIADIS ARTE-MIOS K., CHRISTINA DARVIRI 2017. Pythagorean Self-Awareness serves effectively for Stress Management on Freshmen: A quasi-experimental study. SOCRATES, 5, 15-37.
  • SCHUBERT, C., LAMBERTZ, M., NELESEN, R. A., BARDWELL, W., CHOI, J. B. & DIMSDALE, J. E. 2009. Effects of stress on heart rate complexity–a comparison be-tween short-term and chronic stress. Biological psychology, 80, 325-332.
  • MARTIN ROD, A., KUIPER NICHOLAS, A., OLINGER L, J. & DANCE KATHRYN, A. 1993. Humor, coping with stress, self-concept, and psychological well-being. Humor – International Journal of Humor Research.
  • WOODY, M. L., ROSEN, D., ALLEN, K. B., PRICE, R. B., HUTCHINSON, E., AMOLE, M. C. & SILK, J. S. 2018. Looking for the negative: Depressive symptoms in adolescent girls are associated with sustained attention to a potentially critical judge during in vivo social evaluation. J Exp Child Psychol, 179, 90-102.
  • LOUGHEED, J. P., CRAIG, W. M., PEPLER, D., CONNOLLY, J., O’HARA, A., GRANIC, I. & HOLLENSTEIN, T. 2016. Maternal and Peer Regulation of Adolescent Emotion: Associations with Depressive Symptoms. J Abnorm Child Psychol, 44, 963-74.

Αφήστε μια απάντηση

Η ηλ. διεύθυνση σας δεν δημοσιεύεται. Τα υποχρεωτικά πεδία σημειώνονται με *