Sleep deprivation scale for children and adolescents

Mehmet Kandemir1 , Edanur Bozdemir2 , Yunus Hayran1 , Zahide Tonga1 , Aslı Kandemir3 1 Kırıkkale University, Faculty of Education, Department of Guidance and Psychological Counseling, Kırıkkale, Turkey 2Kırıkkale University, Social Sciences Institute, Department of Guidance and Psychological Counseling, Kırıkkale, Turkey 3 Turkish Ministry of National Education, Kırıkkale, Turkey ABSTRACT ARTICLE INFO The aim of the study is to develop a scale that is capable of measuring to determine the sleep deprivation levels of children and adolescents. To study the validity and reliability of the Sleep Deprivation Scale for Children and Adolescents, two separate research groups were formed with the appropriate sampling method based on accessibility and availability. The first stage research group, in which the structure validity was determined, people of a total of 201, 77 (38.3%) male and 124 (61.7%) female. The second stage research group, in which the emerging structure was confirmed, of 254 people, 8 (34.6%) male and 166 (65.4%) female. As a result of the analyzes made for the sampling adequacy of the scale, while Kaiser-Meyer-Olkin (KMO) = .94; Bartlett Test result was found to be χ2 = 1833.03 (p <.00). As a result of the Explanatory Factor Analysis (EFA), It has been found that the scale has a single factor structure. In addition, it was found that the single factor structure of the scale explained 54.48% of the variance and the internal consistency reliability coefficient was .94. Then, the verification of the one-dimensional structure was started. As a result of the Confirmatory Factor Analysis (CFA), It was seen that the Chi-Square / Degrees of Freedom (254.94 / 65), 3.92; RMSEA values ​​was .07 and the RMR values ​​was .027. When the fit coefficients obtained for the tested model are examined, it is seen that CFI = .94, GF3 = .91, AGFI = .91, IFI = .96, NFI = .94 and TLI = .97. According to the data obtained, it can be said that a valid and reliable scale has been developed. Article History: Received: 06.02.2021 Received in revised form: 07.03.2021 Accepted: 10.03.2021 Available online: 06.01.2021 Article Type: Standard Paper Keywords: Sleep, sleep deprivation, sleep deprivation scale, child, adolescent © 2021 JIETP All rights reserved1 Extended Summary 1. Introduction Sleep, which is defined as a life phase that can occur spontaneously, where the organism can reverse its interaction with the outside world with different stimuli, creates a temporary unconscious (Guytun, 1996). It is known that it is one of the important factors affecting the learning and developmental processes of children in school age (Walker, 2005). In childhood and adolescence, when learning and developmental processes are very fast, it is very valuable and important to determine whether sleep, which has a high effect on these processes, is sufficient for children and adolescents. Therefore, an examination of the increasing sleep deprivation experienced by children and adolescents during the day and to analyze which variables it is related to. It is possible to say that there are limited measurement tools to determine how the increasing sleep deprivation affects 1 Corresponding author’s address: Kırıkkale University, Faculty of Education, Department of Guidance and Psychological Counseling, Kırıkkale, Turkey e-mail: zahidetonga@gmail.com DOI: https://doi.org/10.47157/jietp.875187 Kandemir, Bozdemir, Hayran, Tonga & Kandemir 49 children and adolescents during the day. Project, with this study, it was aimed to develop a valid and reliable scale for determining the sleep deprivation levels of children and adolescents. 2. Method Two separate research groups were formed with the appropriate sampling method in order to carry out the validity and reliability study of the Sleep Deprivation Scale for Children and Adolescents. The first stage, the construct validity was determined, where of a total of 201 people, 77 (38.3%) male and 124 (61.7%) female. The second stage research group, in which the structure was confirmed, of 254 people, 8 (34.6%) male and 166 (65.4%) female. It is seen that the average age of the first group from the study groups is 12.37, and the average age of the second group is 11.87. Before the analysis, Z scores were examined in terms of extreme values. As a result of the examination, it was determined that there were 3 data that were seen to be out of the +3 and -3 values ​​and they were removed from the data set. Then, Exploratory and Confirmatory Factor Analyzes were conducted on the data collected from the research group. One of the prerequisites of Exploratory Factor Analysis used to test construct validity in the scale development process is the absence of multiple and dual / uniqueness problems (Tabachnick & Fidel, 2001). Correlation analysis was performed to determine whether this problem existed. As a result of the test, it was determined that the correlation coefficients between items were between .15 and .69. According to the correlation analysis result, it was decided that there was no multi-linearity and singularity problem for the data set created for the validity and reliability analysis of the scale. 3. Findings As a result of the analysis for the sampling adequacy of the scale, Kaiser-Meyer-Olkin (KMO) was found as .94; Bartlett Test result was found to be χ2 = 1833.03 (p <.00). As a result of the Explanatory Factor Analysis (EFA), it has been found that the scale has a single factor structure. In addition, it was found that the single factor structure of the scale explained 54.48% of the variance and the internal consistency reliability coefficient was .94. Then, the verification of the one-dimensional structure was started. As a result of the Confirmatory Factor Analysis (CFA), It was seen that the Chi-Square / Degrees of Freedom (254.94 / 65), 3.92; RMSEA values ​​was .07 and the RMR values ​​was .027. When the fit coefficients obtained for the tested model are examined, it is seen that CFI = .94, GF3 = .91, AGFI = .91, IFI = .96, NFI = .94 and TLI = .97. 4. Discussion and Results The scale structure determined as a result of the research has been discussed by comparing it with different research results (Johns, 1991; Spilsbury, Drotar, Rosen & Redlin, 2007) in the literature. In the sleep deprivation scale prepared by Spilsbury et al. (2007), it is seen that there are four different structures: sleep in school, wakefulness in school, sleep after school and sleep during school journey. It is seen that the scale items and scope prepared by Spilsbury et al. (2007) are quite similar to the scale items and scope prepared by us. In the study, the results of eigenvalue, slope trend graph, structure validity showed the one-dimension structure of the scale clearly different from the study of Spilsbury et al. As a result of the Exploratory Factor Analysis, Cronbach’s alpha internal consistency analysis, item total correlation analysis, Confirmatory Factor Analysis and other analyzes used in the development of the Sleep Deprivation Scale for Children and Adolescents, it is possible to say that the measurement efficiency and reliability of the scale are quite good. Consequently, it is possible to say that a scale has been developed that can be studied with many concepts and issues related to the hypothesis that it may be related to the sleep deprivation and quality of children ands who continue their school life (success, problem solving, test and performance anxiety, fear, trauma, depression, self esteem, etc.), when the scope of the scale is considered in terms of its items and findings. It is considered important to determine the relationship between the Sleep Deprivation Scale for Children and Adolescents and the scales that determine sleep problems. Journal of Individual Differences in Education, 2021, 3(1), 48-61 © 2021 Journal of Interdisciplinary Education: Theory and Practice (JIETP) is an EDUGARDEN publication. Sleep Deprivation Scale for Children and Adolescents Mehmet Kandemir1 , Edanur Bozdemir2 , Yunus Hayran1 , Zahide Tonga2 1 , Aslı Kandemir3 1 Kırıkkale University, Faculty of Education, Department of Educational Sciences, Guidance and Psychological Counseling USA, Kırıkkale, Turkey 2Kırıkkale University, Institute of Social Sciences, Kırıkkale , Turkey 3 Turkish Ministry of National Education, Kırıkkale, Turkey ABSTRACT MAK ALE BİLGİ The purpose of the research is to develop a scale with measurement adequacy to determine the sleep deprivation levels of children and adolescents. For the validity and reliability study of the Sleep Deprivation Scale for Children and Adolescents, two separate research groups were formed with the convenience sampling method based on accessibility and convenience. The first stage research group, in which construct validity was determined, consisted of a total of 201 individuals, 77 (38.3%) male and 124 (61.7%) female; The second stage research group, in which the resulting structure was confirmed, consisted of a total of 254 people, 8 (34.6%) men and 166 (65.4%) women. As a result of the analyzes made for the sample adequacy of the scale, Kaiser-Meyer-Olkin (KMO) = .94; Bartlett Test result was found as χ2=1833.03 (p<.00). As a result of Exploratory Factor Analysis, it was found that the scale had a single factor structure. In addition, it was found that the single factor structure of the scale explained 54.48% of the variance and the internal consistency reliability coefficient was .94. Then, the verification of the one-dimensional structure was started. As a result of the Confirmatory Factor Analysis, Chi-Square/Degree of Freedom (254.94/ 65), 3.92; It is seen that the RMSEA values ​​are .07 and the RMR value is .027. When the fit coefficients for the tested model are examined, it is seen that CFI=.94, GF3=.91, AGFI= .91, IFI=.96, NFI=.94 and TLI= .97. According to the data obtained, it can be said that a valid and reliable scale has been developed. Article History: Retrieved: 06.02.2021 Revised: 07.03.2021 Accepted: 10.03.2021 Published online: 06.01.2021 Article Type: Research Article Keywords: Sleep, sleep deprivation, sleep deprivation scale, child, adolescent © 2021 JIETP All rights reserved 1. Introduction People have to meet their basic needs in order to continue their lives and maintain their quality of life. In addition to basic needs such as food and beverage, security and shelter, it can be said that sleep and sleep health is an important and basic need for the human organism in terms of physiological and psychological health. There are important researchers explaining that sleep is a basic need and that this need is a prerequisite for biological and psychological empowerment (Gerrig & Zimbardo, 2012; Glasser, 1989; Maslow, 1943). In particular, Maslow (1943) evaluated sleep within the basic biological needs in the hierarchy of self-actualization and specified biological needs as a prerequisite for other steps. Glasser (2989), on the other hand, emphasized the importance of sleep by stating that one of the five basic needs for psychological health is the need for survival, including sleep. Sleep, which is very important for human nature; It is defined as a life stage that can occur spontaneously, that the organism can reverse its interaction with the outside world with different stimuli, and that creates a temporary state of unconsciousness (Guyton, 1996). Çalıyurt (1998), on the other hand, considers sleep not as an inactivity that allows the organism to rest, but as a life stage that provides the necessary energy for the body to actively renew itself and continue its life. Although sleep has a holistic view, it consists of two main phases (Guyton & Hall, 2011). The first stage of sleep is defined as the REM stage and is known as the stage where rapid eye movements and muscles begin to relax and go to sleep. Second phase NONREM phase 1 Corresponding AuthorAddress: Kırıkkale University, Faculty of Education, Department of Educational Sciences, Department of Guidance and Psychological Counseling, Kırıkkale, Turkey e-mail: zahidetonga@gmail.com DOI: https://doi.org/1047157/jietp. It is defined as 875187 Kandemir, Bozdemir, Hayran, Tonga & Kandemir 51 (Owens & Witmans, 2004). The NONREM phase consists of slow eye movements. This stage constitutes almost 75-80% of the total sleep time and is divided into four stages in itself (Ismayilova, 2014). The first and second stages are called superficial slow sleep, and the third and fourth stages are called deep slow sleep. As you go from the first stage to the fourth stage, sleep deepens. Fatigue is seen when deep sleep is not slept. The first NONREM sleep lasts 70-100 minutes, and most of it passes in stage 3-4. During the night, the duration of REM sleep gradually decreases and stage 3-4 shortens. Morning sleep consists predominantly of REM and stage 2 NONREM. Likewise, as age progresses, the 3rd and 4th stages shorten. In the third and fourth phases, it is very difficult for the person to be awakened and it may take up to 5 minutes to become fully awake. During the night’s sleep of a normal healthy individual, these phases repeat successively 4-6 times. When the person first falls asleep, the first four phases of non-REM sleep are passed and REM sleep begins (Guyton 1996). Average night sleep, with NONREM phases; It is known that 2-5% of them are stage 1, 45-55% are stage 2, 20-25% are stage 3, and 20-25% are REM stages (Gerrig and Zimbardo, 2012; Owens and Witmans). , 2004). Sleep is seen as a basic requirement for maintaining a healthy lifestyle and it is stated that people have this need from birth (Gerrig & Zimbardo, 2012). Sleep, which constitutes one-third of human life, has a basic function for the growth and development of the individual from birth; It fulfills many important functions such as learning, memory, information processing, cognitive development, tissue regeneration, strengthening the immune system (Aydın & Karaca, 1998; Campbell, Elder, Galland, & McDowall, 2017; Daşdemir, 2012; Guyton, 1996; Kaplan, Liu, Liu, and Owens, 2005; Lillis, Prisecilla, and Taylor, 2001; Oginska and Pokorski, 2006). Sleep is a regular cycle that can affect individuals’ body systems in various ways. Every individual has a sleep need that must be met daily. These sleep durations/amounts vary according to age (Daşdemir, 2012). Considering the studies on sleep duration; 9-11 hours in children aged 6-13 years; 8-10 hours of sleep is recommended for adolescents (Albert, Alessi, Bruni, DonCarlos, Hirshkowitz, & Whiton, 2015). In some studies, it is stated that school-age children need about 9-10 hours of sleep per day. (Farney, Jensen, Walker, & Walker, 1986; Güleç, 2003; Thiedke, 2001). According to Lee, Rankin, and Ward (2007), sleep is the basic element of child development. Accordingly, one out of every four children has sleep problems (Meltzer & Mindell, 2004). More than 30% of primary school children and 70% of teenagers experience sleep deprivation (Keskin, 2016). This sleep deprivation problem; It has important consequences in many areas of the lives of children and young people. In the study conducted by Bülbül, Kurt, Ünlü, and Kırlı (2010), it was concluded that selective attention and decision-making mechanisms were weaker in children and adolescents who reported shorter sleep. Gruber, Raviv, and Sadeh (2002) stated in their study that sleep deprivation causes impairment in memory and information processing processes, along with the disruption of cognitive functions. Sleep problems that occur in children and adolescents reflect negatively on their learning processes and also manifest as problems/problems in behavior patterns in daily life (Aydın & Yetkin, 2014; Kelman, 1999). There are studies showing that sleep causes mood changes and feeling depressed in children and adolescents who cannot sleep adequately and have sleep deprivation (Kelman, 1999). The most important function of sleep is to restructure its emotion regulation capacity (Dahl & Lewin, 2002). When adequate amount of sleep is not met, it is concluded that there is low energy, anxiety, irritability, and difficulty in controlling emotions. (Blum and Carey, 1996; Dahl, 1996). In a study conducted with adolescents, results are expressed that insufficient sleep duration increases depressive mood and thoughts of self-harm. (Bautista, Foo, Shin, & YK, 2013). In another study by Fuligni and Hardway (2006); When the writings of children between the ages of 14-15 who keep a diary are examined; It is emphasized that children who sleep less describe their own emotional states more negatively. Journal of Interdisciplinary Education: Theory and Practice, 2021, 3(1), 48-61 52 Unlike sleep deprivation, sleep deprivation is a state of sleep deprivation that occurs as a result of the individual’s delaying the need for sleep during the day, either because of the circumstances or willingly. is expressed. (Terman and Terman, 2001). Sleep deprivation affects children’s physical growth, brain development, immune system and is known to play an important role in weight gain. Sleep deprivation causes a decrease in growth hormones (Akerstedt, Froberg, & Friberg, 1979; Akerstedt, Froberg, & Palmblad, 1979; Beck, 1981), which can cause problems such as slow growth and slow weight gain, especially in children. Research by Arlet, Jennifer, Kilkus, and Nedeltcheva (2009) concluded that appetite-controlling hormones (leptin-ghrelin hormones) may change due to sleep deprivation. Getting too little or too much sleep can be associated with abnormal weight gain. In a study conducted by Karaçal (2010), it was concluded that there is a link between not getting enough sleep and being overweight. In addition, in a longitudinal study conducted by Fredriksen, Reddy, Rhodes, and Way (2004) with 6th, 7th, and 8th grade students who reported short sleep duration, a decrease in students’ self-confidence was found. In addition, there are studies in the literature that children with sleep deprivation have negative body image and low self-esteem (Deane, Fallone, & Owens, 2002; Owens, 2001). There are important studies emphasizing the relationship between sleep processes (Carskadon 2002; Carskadon & Wolfson, 1998; Walker, 2005). Carskadon and Wolfson (1998) found that students with sufficient sleep time were more successful in difficult lessons than students with sleep deprivation, and that they were more likely to answer complex math questions than students with sleep deprivation. well understood, read They reported that their comprehension skills and motivation to learn were higher and they received higher grades. In the studies conducted by Blum and Carey (1996) and Garrity (2007), it was found that the sleep deprivation experienced by students caused attention and motivation problems, and it was stated that sleep loss in children reduced verbal creativity and abstract thinking ability. Bonnie, Findley and Levinson (1992) stated that sleep deprivation increases the risk of accidents and injuries during the day and emphasized attention and coordination problems in individuals who have sleep problems. In the literature on sleep processes of children and adolescents, differences in sleeping and waking times on weekdays and weekends, early school starts, social activities, high interaction with technology during the day, increased homework, decreased parental control are associated with sleep quality and deprivation of children and adolescents. It is stated that it is related (Carskadon 2002; Ward, Rankin, & Lee, 2007). In addition to these, there are also studies that have found that the affected sleep quality causes sleep deprivation during the day and that this may cause chronic fatigue that may affect school performance (Carskadon & Wolfson, 1998; Badia, Burduvali, Drake, Jefferson, Nickel, & Roth, 2003). . In the light of all these studies in the literature, it can be concluded that the effect of sleep on the lives and learning processes of school-age children and adolescents is quite important. Considering in terms of the above explanations, the sleep health of children and adolescents is not only for biological development; It is seen that it is also very important in terms of academic development such as learning, understanding, memory, attention, success, and sustainable motivation. Accordingly, it is thought that it will be valuable in terms of investigating the sleep experiences of children and adolescents, determining the effects of different living areas and protective studies. When the literature is examined, it is seen that there are scale studies to determine sleep and sleep deprivation (Önder, Masal, Demirhan, Horzum, & Beşoluk, 2016; İzci, Ardıç, Fırat, Şahin, Altınörs, & Karacan, 2008). It is seen that the sleep scale adapted to Turkish by İzci et al. (2008) can be used on adults. It has been observed that the scale items, developed by Meijer and Van Den Wittenboer (2004) and adapted into Turkish by Önder and Kandemir, Bozdemir, Hayran, Tonga & Kandemir 53 colleagues (2016), are not related to sleep deprivation that is increasingly experienced during the day and are related to not being able to sleep at night. It was observed that the sleep deprivation scale prepared by Spilsbury et al. (2007) to determine the increasing sleep deprivation in adolescents was for adolescents only and there were adolescents diagnosed with sleep problems in the study group. As a result, it is thought that a valid and reliable measurement tool with the ability and stability to measure is needed to determine the increasing sleep deprivation of children and adolescents during the day and the reflections of this deprivation on daily life. 2. Method 2.1. Research Group For the validity and reliability study of the Sleep Deprivation Scale for Children and Adolescents, two separate research groups were formed to be used in Exploratory and Confirmatory Factor Analysis with the convenient sampling method (Berg, 2001) based on accessibility and convenience. The research group formed in the first stage was formed to carry out the basic structure and reliability studies of the scale; The research group created in the second stage was formed to determine to what extent the structure obtained in the first stage was confirmed in a different data set by Confirmatory Factor Analysis. In the research group formed for the first stage, there are a total of 201 people, 77 (38.3%) men and 124 (61.7%) women. According to Bryman and Cramer (2001), in the scale development process, the number of scale items of the research group should be multiplied by 5 and 10. With a similar explanation, Kline (1994) states that it is sufficient for the sample size to be 10 times the number of items. According to these explanations, it is considered that the number of samples reached in this study is sufficient. The ages of the research group vary between 8 and 17, and the average age is 12.37. At the same time, some statistical data were collected from the children and adolescents in the research group on daily sleep times, sleeping hours and sleeping hours. According to this, 15 (7.5%) of the individuals in the research group were less than six hours, 78 (38.8%) between six and eight hours, 90 (44.8%) between eight and ten hours, and finally 18 (38.8%) of them. 9) have a daily sleep duration of ten hours or more; It is seen that 11 (5.5) of them started to sleep before 22:00, 84 (41.8%) started to sleep between 22:00 and 00:00, and 104 (51.7%) started to sleep after 00:00. In the research group formed for the second stage in the development of the scale, there were a total of 254 people, 88 (34.6%) male and 166 (65.4%) female. The ages of the research group vary between 8 and 17, and the average age is 11.87. At the same time, some statistical data were collected from the children and adolescents in the research group on daily sleep times, sleeping hours and sleeping hours. Accordingly, 12 (4.7%) of the individuals in the research group were less than six hours, 88 (34.6%) between six and eight hours, 134 (52.8%) between eight and ten hours, and finally 20 (7.9%) of them. ) have ten hours or more of daily sleep; It was determined that 22 (8.7) of them started to sleep before 22.00, 124 (48.8%) started to sleep between 22.00 and 00.00, and 108 (51.7%) started to sleep after 00.00. 2.2. Data Collection Tools Personal Information Form: Within the scope of the research, a Personal Information Form was created in order to evaluate children and adolescents in terms of demographics. In the prepared form, there are questions about the evaluation of the research group in terms of gender, age and sleep duration. Sleep Deprivation Scale for Children and Adolescents-Expert Opinion Form: In the context of the validity and reliability study of the Child and Adolescent Sleep Deprivation Scale, this form was created for experts to evaluate the item pool prepared for the sleep needs of school-going children. In the Expert Opinion Form, the experts are asked to score between 0 and 10 points regarding the suitability of the items created in the Journal of Interdisciplinary Education: Theory and Practice, 2021, 3(1), 48-61 54 and suggestions for each item. Sleep Deprivation Scale for Children and Adolescents-Application Form: This form was created for the application after the item pool prepared for the validity and reliability study of the Sleep Deprivation Scale for Children and Adolescents and the expert evaluation. In addition to the validity and reliability process of this form, the psychometric evaluation results are given in the findings section of the study. 2.3. Data Collection Process and Preparation of Data for Analysis The data collection process in the research was carried out online due to the Covid-19 Pandemic. After the data collected via Google Form were entered into IBM SPSS, the data were prepared for analysis. In this context, the z scores of the data were examined in terms of extreme values, it was determined that there were 3 data that were outside the +3 and -3 values, and they were removed from the data set. One of the prerequisites of Exploratory Factor Analysis, which is used to test construct validity in the scale development process, is the absence of multiple and dual/singularity problems (Tabachnick & Fidel, 2001). Correlation analysis was performed to determine whether this problem exists and as a result of the test, the correlation coefficients between the items were determined to be between .15 and .69. According to the correlation analysis result, it was decided that there was no problem of multicollinearity and singularity for the data set created for the validity and reliability analysis of the scale. 3. Findings In the process of developing the Sleep Deprivation Scale for Children and Adolescents, the theoretical foundations of sleep, sleep deprivation and sleep quality were primarily examined by researching the relevant literature. After the review, a 20-item “Sleep Deprivation Scale Item Pool for Children and Adolescents” was created within the scope of the sleep deprivation literature. At the same time, while creating the items, the rules of article writing were taken into consideration. Then, the item pool created for the scale was directed to 5 people working as experts in the field for their evaluation. In the context of the evaluations from the experts, 3 items were removed from the scale and 2 items were corrected. After the evaluations from the experts, the number of items before the implementation of the Sleep Deprivation Scale for Children and Adolescents decreased to 17. At the same time, when the scores given by the experts to the scale items were examined, it was seen that they varied between 7-10 points and the average score was found to be 8.7. After these procedures, the data collection process was started from the research group in order to determine the construct validity of the 17-item Likert scale, which was prepared as “strongly disagree”, “disagree”, “agree” and “strongly agree”. Information about the data collection process and the preparation of the data for analysis is explained in detail in the method section of the research. The Explanatory Factor Analysis process was started on the data collected by the application form of the Sleep Deprivation Scale for Children and Adolescents and prerequisite analyzes were made. Açımlayıcı Faktör Analizi, faktörler ile göstergeleri arasında tanımlanan ilişkileri açıklayan ölçme modellerini test etmek için kullanılan çok değişkenli istatistik yöntemidir (Çokluk, Şekercioğlu, Büyüköztürk, 2012). Jöreskog ve Sörbom (1993) ise, gözlenen ölçümlerdeki, varyansın ve kovaryansın gizli kaynaklarını belirleyerek ölçeğin yapı geçerliliğini belirlemek için kullanılan bir yöntem olarak Açımlayıcı Faktör Analizini açıklamaktadır. Ölçeğin, geçerlik ve güvenirlik analizleri için birinci araştırma grubundan toplanan verilerin analizi sonrasında, Kaiser-Meyer-Olkin (KMO) = .94 olarak bulunurken; Bartlett Testi sonucu χ2=1833.03 (p<.00) bulunmuştur. Araştırmada KMO değerinin oldukça yüksek olduğu, Bartlett testinin anlamlı olduğu bulunmuş ve bu sonuçlara göre, araştırmanın örneklem büyüklüğünün mükemmel olması anlamına geldiği, literatür bilgisi bağlamında değerlendirilmiştir (Sharma, 1996). Ölçek maddelerinin faktör yük değerlerini belirlemek için kesme noktası olarak .40 belirlenmiştir. Büyüköztürk (2007), faktör yük değerinin sosyal bilimler için .30’un alt sınır olarak kabul edilebileceğini belirtmiştir. Açıklayıcı Faktör Analizi sonucunda, ilk olarak maddelerin ortak Kandemir, Bozdemir, Hayran, Tonga & Kandemir 55 faktördeki varyansı birlikte açıklama düzeyleri incelenmiştir. Buna göre, 2 madde .40’ın altında olduğu belirlenmiş ve bu 2 madde veri setinden çıkartılarak analizler tekrarlanmıştır. Bu işlemin arkasından yapılan analiz sonucunda, ölçeğin kaç faktörlü olabileceğine ilişkin öz değerler incelenmiş ve 1’in üstünde tek faktörün olduğu bu inceleme sonrasında ortaya çıkmıştır. Öz değerlerin 1 ve üzerinde olması faktörün kararlığını göstermektedir (Çokluk, Şekerçioğlu, Büyüköztürk, 2012). Elde dilen tek faktörlü yapının öz değerinin 8.17 olduğu belirlenmiş ve dolayısıyla kararlılık gösteren tek bir faktörün olduğu değerlendirilmiştir. Tek faktörlü yapıyı görmek için aynı zamanda, Cattel’in yamaç eğim testi yapılmıştır. Kline’e (1994) göre bu test, en fazla anlamlı faktör sayısını belirgin hale getirmek amacıyla kullanılır. Yamaç eğilim analizi sonucunda, aşağıda verilen, Şekil 1’e ulaşılmıştır. Şekil 1. Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeği ile ilgili yamaç eğim grafiği Şekil 1’deki grafiğe göre, ölçeğin tek kırılma noktasının olduğu görülmektedir. Tabachnick ve Fidel’e (2001) göre, değerlendirmelerde faktörler arasında keskinliği, belirginliği ve anlamlılığı sağlamak için döndürme (rotation) yapılması gerekmekte, dolayısıyla tek faktörlü bir yapıda bu işleme gerek duyulmamaktadır. Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeğinin yapı geçerliliği çalışmasında tek faktörlü yapı açığa çıktığı için döndürme işlemlerine geçilmemiştir. Bu yüzden Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeği tek boyutlu yapı olarak raporlanmıştır. Tek boyutlu yapıdaki her bir maddeyle ilgili yük değerleri, öz değerleri ve toplam varyans değerleri Tablo 1’de gösterilmiştir. Tablo 1. Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeği açımlayıcı faktör analizi sonuçları Madde No Maddeler Faktör Yükleri Ortak Varyans Değerleri 1 Sabahları uyanırken güçlük çekerim. .842 .387 2 Daha fazla uyku uyuyabilmek için kahvaltı yapmadığım olur. .815 .411 3 Kahvaltı sırasında kendimi uykulu hissederim. .808 .542 4 Okula giderken kendimi uykulu hissederim. .790 .624 5 Dersleri dinlerken kendimi uykulu hissederim. .782 .664 6 Derslerde kendimi esnerken yakalarım. .781 .590 7 Ders sırasında zihnimi açık hissetmem. .768 .450 8 Teneffüslerde dışarı çıkmak yerine sınıfta uyurum. .757 .404 9 Okuldan eve gelir gelmez uyku ihtiyacı hissederim. .737 .474 10 Öğle yemeğinden sonra kendimi uykulu hissederim. .689 .470 11 Ödev yaparken uykum gelir. .685 .612 12 Gün içinde kendimi uyuşuk hissederim. .671 .610 13 Yeteri kadar uykumu alamadığım için kendimi gün içinde yorgun hissederim. .641 .653 14 Uykusuzluk nedeniyle günlük aktiviteleri unuttuğum olur. .635 .573 15 Uyku ile ilgili gün içinde şikâyetlerim olur. .622 .708 Açıklanan Varyans Değer: 54.48 Faktör Öz Değerleri: 8.17 Journal of Interdisciplinary Education: Theory and Practice, 2021, 3(1), 48-61 56 Tablo 1 incelendiğinde, Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeğinin her bir maddelerine ilişkin faktör yük değerlerinin .622 ile .842 arasında değiştiği görülmektedir. Aynı zamanda, Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeğinin tek faktörlü yapısının varyansın %54.48’ini açıkladığı ortaya çıkmıştır. Henson ve Roberts’a (2006) göre, açıklanan varyans oranının % 50’nin üstü olması, ölçeğin ölçme düzeyinin yüksek olması anlamına gelmektedir. Scherer, Wieb, Luther ve Adams’a (1988) göre ise %40 ile %60 arasında değişim gösteren açıklanan varyans düzeyleri oldukça yeterli bir düzeydir. Bu açıklamalara göre, Açımlayıcı Faktör Analizi sonucunda elde edilen varyans değerinin (%54.48) oldukça iyi olduğu ve ortaya çıkan tek faktörlü yapının ölçme yeteneğinin yeterli olduğu ifade edilebilir. Açımlayıcı Faktör Analizi sonrasında ortaya çıkan sonuçların, güvenilirliğini belirlemek amacıyla madde analiziyle yapılan, Cronbach alfa iç-tutarlılık değerleri incelenmiştir. Analiz sonrasında çıkan katsayı değerinin .94 olduğu belirlenmiştir. Özdamar (1999), .81 ile 100 arası güvenirlik katsayılarını yüksek düzeyde güvenirlik olarak tanımlamıştır. Buna göre, analiz sonrasında bulunan iç tutarlılık katsayısının oldukça yüksek bir değer olduğunu söylemek mümkündür. Aynı zamanda, güvenirlik çalışması yapılan “Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeği”nde yer alan maddelerin, madde istatistiği olarak madde toplam korelâsyonu hesaplanmıştır. Bu analiz ile, her bir maddeden elde edilen uyku yoksunluğu puanı ile toplam uyku yoksunluğu puanı arasındaki ilişki anlamında kullanılmakta olup her bir uyku yoksunluğu maddesinin korelasyon katsayısı hesaplanmıştır. Analiz sonrasında çıkan sonuçlar Tablo 2’de verilmiştir. Tablo 2. Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçek maddelerine ait istatistikler Madde ortalaması Madde standart sapması Madde Toplam Korelasyonu Madde Silme Güvenirlik Katsayısı Madde 1 2.593 1.045 .574 .938 Madde 2 1.954 1.078 .593 .938 Madde 3 2.129 1.032 .693 .935 Madde 4 2.293 1.101 .750 .934 Madde 5 2.237 1.045 .779 .933 Madde 6 2.299 1.034 .722 .934 Madde 7 2.072 .984 .622 .937 Madde 8 1.541 .858 .585 .938 Madde 9 1.871 .996 .637 .936 Madde 10 1.732 .965 .636 .936 Madde 11 2.216 1.045 .738 .934 Madde 12 1.948 .953 .735 .934 Madde 13 2.201 1.000 .764 .933 Madde 14 1.855 .970 .710 .935 Madde 15 2.056 1.029 .807 .932 Ölçeğin geliştirilmesi sürecindeki analizler sonrasında “Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeği”nin çocuk ve ergenlerin uyku yoksunluğunu ölçme yeteneğine sahip olduğunu söylemek mümkün olsa da, ölçekten elde edilen yapının farklı bir veri setinde doğrulanması amacıyla, araştırmanın ikinci aşaması için toplanan verilerle Doğrulayıcı Faktör Analizi çalışması y apılmıştır. Sümer’e (2000) göre, Doğrulayıcı Faktör Analizi ile boyutlar arasında oluşan ilişkiler, karşılaştırmalı hipotez modelleri test edilebilir ve modellerin iyilik derecesi belirlenmektedir. Doğrulayıcı Faktör Analiz çalışmaları, son zamanlarda ölçek geliştirme ve uyarlama temelli araştırmalarda yaygın bir şekilde kullanılmaktadır (Çapa, Çakıroğlu ve Sarıkaya, 2005). Açımlayıcı Faktör Analizi ile belirlenen tek boyutlu yapının 15 gözlenen değişkenden oluşan modelin analizi için Doğrulayıcı Faktör Analizine geçilmiştir. Buna göre, modelde ölçeğin temel yapısı Doğrulayıcı Faktör Analizine tabi tutularak uyum değerleri ortaya çıkmıştır. Elde edilen sonuçlara göre, KiKare/Serbestlik Derecesi (254.94/ 65), 3.92; RMSEA değerleri .07 ve RMR değerinin .027 olduğu görülmektedir. Test edilen modele ilişkin elde edilen uyum katsayıları incelendiğinde, CFI=.94, Kandemir, Bozdemir, Hayran, Tonga & Kandemir 57 GF3=.91, AGFI= .91, IFI=.96, NFI=.94 ve TLI= .97 olduğu görülmektedir. CFI, GFI, IFI, NFI, TLI gibi uyum değerlerinin .90 ve .90 yakın olduğu görülmektedir. Ki-Kare değerinin 5’ten, RMSEA ve RMR değerinin ise .08’den küçük olması önerilen modelin uyum iyiliğinin yeterli olduğu anlamına gelmektedir (Şimşek, 2007). Doğrulayıcı Faktör Analizi sonucunda uyum iyiliği puanlarının yeterli olmasından dolayı iyileştirme indeksleri incelenmemiş olup, analiz sonucunda, madde ve tek fakötörlü yapı arasındaki ilişki değerlerine ait standardize edilmiş katsayılarla ilgili bulgular Şekil 1’te verilmiştir. Şekil 2. Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeğinin doğrulayıcı faktör analiz sonuç diyagramı Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeğinin geliştirilmesi sürecinde kullanılan Açımlayıcı Faktör Analizi, Cronbach alfa iç-tutarlılık analizi, madde toplam korelasyon analizi, Doğrulayıcı Faktör Analizi ve diğer analizler sonucunda, ölçeğin ölçme yeterliliğinin ve güvenirliğinin oldukça iyi olduğunu söylemek mümkünüdür. 4. Sonuç, Tartışma ve Öneriler Çocuk ve ergenlerin gün içinde yaşadıkları uyku yoksunluğunu belirlemek amacıyla hazırlanan Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeğinin geçerlilik ve güvenirlik çalışması sonucunda, tek boyutlu bir yapı ortaya çıkmıştır. Açımlayıcı faktör analizi sonrasında ortaya çıkan tek boyutlu yapı doğrulayıcı faktör analizi ve farklı güvenirlik hesaplamaları ile de doğrulanmıştır. Bulgular açısından düşünüldüğünde, ölçeğin ölçme yeteneğinin ve duyarlılığının oldukça iyi olduğunu söylemek mümkündür. Alan yazın incelendiğinde, araştırmada açığa çıkan yapının desteklendiğini gösteren Journal of Interdisciplinary Education: Theory and Practice, 2021, 3(1), 48-61 58 sınırlı düzeyde araştırmalar olduğunu söylemek mümkündür (Johns,1991; İzci ve diğ.,2008; Önder ve diğ., 2016). Fakat bu araştırmacıların hazırlamış ya da uyarlamış olduğu uyku kalitesi ile ilgili ölçekler gün içinde artarak yaşanan uyku yoksunluğu ve ihtiyacından çok, gece uykusuna geçememekle ilgili olduğu söylenebilir. Ergenlerde, gün içinde artan uyku yoksunluğunu belirlemek için Spilsbury ve arkadaşları (2007) tarafından hazırlanan uyku yoksunluğu ölçeğinde ise, okul içinde uyku, okul içinde uyanıklık, okul sonrası uyku ve okul yolculuğunda uyku olmak üzere dört farklı yapının olduğu görülmektedir. Spilsbury ve arkadaşlarının (2007) hazırlamış olduğu ölçek maddeleri ve kapsamı, tarafımızdan hazırlanan ölçek maddeleri ve kapsamı ile oldukça benzer olduğu görülmektedir. Araştırmada, öz değer, yamaç eğilim grafiği, yapı geçerlilik sonuçları ölçeğin tek boyutu yapısını Spilsbury ve arkadaşlarının çalışmasına göre, belirgin bir şekilde göstermiştir. Aynı zamanda, Spilsbury ve arkadaşlarının hazırlamış olduğu ölçeğin araştırma grubunu sadece 11 yaş ve üstü ergenler oluşturmuş olup, araştırma grubundaki ergenlerin 62’si uyku sorunu tanısını aldıkları raporlanmıştır. Hazırlanan bu ölçeğin geçerlilik güvenirlik çalışmasında örneklem olarak sadece ergenler değil, çocuklar da bulunmaktadır. Sonuçta, okul yaşamına devam eden çocuk ve ergenlerin uyku yoksunluğu ve kalitesi ile ilişkili olabileceği hipotezi ile ilgili pek çok kavram ve konuyla (başarı, problem çözme, sınav ve performans kaygısı, korku, travma, depresyon, benlik saygısı vb.) çalışılabilecek bir ölçeğin geliştirildiği, ölçeğin kapsamı, maddeleri ve bulgular bağlamında söylenmesi mümkündür. Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeğinin geçerlilik ve güvenirlik çalışması yapılırken bazı sınırlılıkların olduğunu belirtmek gerekir. Araştırma, Covid-19 Pandemisi döneminde yapılmıştır. Birey ve ailelerin bütün yaşam alanlarının etkilendiği ve değişim gösterdiği bu süreçte araştırma verileri toplanmıştır. Bazı öğrencelerin kısmen de olsa okul ve kurslara devam ettiği, uykuyla ilişkili döngülerin değiştiği, ekran karşısında normalden daha fazla kalmak zorunda olduğu, stres kaynaklarının değişim gösterdiği, belirsizliklerin artığı bir dönem olarak bu dönem açıklanabilir. Bu dönemde toplanan veriler ölçek yapısını ve sonuç değerlerini etkileyip etkilemediğinin pandemi sonrasındaki yeni araştırmalarda test edilmesi gerekmektedir. Çocuk ve Ergenler İçin Uyku Yoksunluğu Ölçeğinin, uyku sorunlarını belirleyen ölçeklerle de ilişkilerinin belirlenmesi, ölçeğin psikopatolojik anlamda uyku sorunlarını belirlerken yardımcı bir ölçek olmasına ya da çocuk ve ergenlere yapılacak müdahale programlarını etkililiğini görme açısından yardımcı bir araç olarak ölçeğin kullanılabileceği düşünülmektedir. Kaynakça Akerstedt, T. ,Froberg, JE, & Friberg, Y. (1979). 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