Subjects and methods
A questionnaire survey was conducted in June 1996 on 168 first-grade students [males: 58 (34.5%); females: 110 (65.5%)] enrolled in April 1996 at the Tokyo Municipal Vocational High School A.
The reasons for using the first-grade students as the subjects were because: their health education and instruction should be started soon after their admission from the viewpoint of primary prevention; the first-grade students are likely to have more subjective symptoms than the second- or third-grade students; and understanding the factors is necessary to help them effectively.20
The survey conducted in June 1996 was in the form of group surveys using questionnaires filled in by the students themselves with the cooperation of the home-room teacher. The students were asked to enter their names on the questionnaires for the purpose of data matching.
The survey contents consisted of the following items: (i) 30 items about psychosomatic complaints; (ii) 6 items each about their cognition to fathers, mothers, friends, teachers and friends; (iii) 5 items about their cognition to the schoolwork; and (iv) items about their lifestyle habits (ingestion conditions, sleeping hours etc.). Although Minnesota Multiphasic Personality Inventory (MMPI),21 the Cornell Medical Index (CMI)22 and so forth are used for questionnaires relating to psychosomatic complaints, both of these have many questions. Moreover, they are not used that frequently for Japanese high school students. It was therefore decided to use 30 items pertaining to somatic and psychological complaints currently mentioned most frequently by students with reference to Nippon Hoso Kyokai (NHK) public opinion surveys23 and surveys of the Tokyo Metropolitan Board of Education24 that are used nationwide in Japan for junior high school and senior high school students (Table 1).
Table 1. Mean and factor analysis of psychosomatic complaint items
|Depressive symptoms (α = 0.91)|
|Lack tenacity||1.36 (1.06)||0.78||0.12||0.02||0.13||0.21|
|Get distracted||1.39 (1.05)||0.76||0.21||0.14||0.14||0.11|
|Irritated without any reasons||1.27 (1.18)||0.75||0.04||0.18||0.14||0.08|
|Somehow feel sick||1.06 (1.02)||0.73||0.28||− 0.02||0.10||0.02|
|Tired of talking with other people||1.29 (1.12)||0.72||0.16||0.13||0.07||0.06|
|Get in no mood to do anything||1.78 (1.16)||0.68||0.28||0.21||0.17||− 0.09|
|Feel gloomy||1.48 (1.06)||0.64||0.33||0.07||− 0.05||− 0.07|
|Difficulty in putting my thoughts together||1.46 (1.10)||0.63||0.35||0.18||− 0.02||− 0.01|
|Relationship between me and my friends gets bad||0.99 (0.94)||0.63||0.09||0.19||− 0.20||0.12|
|Like shouting||1.54 (1.17)||0.60||0.18||0.07||0.08||0.07|
|Physical symptoms (α = 0.83)|
|Catch a cold||0.93 (1.00)||0.08||0.67||− 0.09||− 0.04||0.20|
|Tired easily||1.57 (0.99)||0.37||0.65||− 0.06||− 0.04||0.05|
|Headache||0.83 (0.90)||0.17||0.63||0.30||0.07||− 0.01|
|Stiffness in the shoulder||1.29 (1.15)||0.21||0.58||0.11||0.18||− 0.01|
|Dizziness when I stand up||1.48 (1.09)||0.13||0.57||0.23||0.23||0.14|
|Heavy in the head||1.05 (0.98)||0.31||0.56||0.35||0.04||− 0.08|
|Heavy in the stomach or nausea||0.72 (0.95)||0.04||0.55||0.19||0.21||− 0.09|
|Pain in the chest||0.62 (0.86)||0.18||0.47||0.34||− 0.16||0.33|
|Like lying||1.79 (1.12)||0.28||0.46||0.15||0.13||− 0.06|
|Sleep badly||1.04 (1.08)||0.28||0.41||− 0.01||0.12||− 0.05|
|Neurotic symptoms (α = 0.65)|
|Palpitation without any reasons||0.55 (0.87)||0.06||0.28||0.71||0.02||0.04|
|Numbness or trembles in the arms or legs||0.33 (0.65)||0.14||0.05||0.62||0.25||0.09|
|Tic||0.86 (0.97)||0.13||0.17||0.52||− 0.02||− 0.05|
|Suddenly feel difficulty in breathing||0.44 (0.78)||0.19||0.44||0.51||− 0.19||0.37|
|Eat too much when I have some uneasiness||0.39 (0.77)||0.44||− 0.13||0.49||0.08||− 0.12|
|Digestive symptoms (α = 0.69)|
|Stomach ache||0.75 (0.88)||0.19||0.36||0.16||0.71||− 0.02|
|Allergic symptoms (α = 0.32)|
|Allergic rhinitis||0.73 (1.14)||0.06||0.01||− 0.11||− 0.01||0.76|
|Atopic dermatitis||0.27 (0.72)||0.01||− 0.09||0.23||0.34||0.63|
|Asthma attack||0.26 (0.67)||0.21||0.15||− 0.01||− 0.21||0.33|
|Factor contribution rate|| ||29.60||7.60||5.20||5.00||4.40|
The items about their cognition to their friends and teachers, and schoolwork were decided with reference to the study by Okayasu et al.25 Okayasu's survey targets junior high school students. This report covers students in the first grade of senior high school. Most of the students are 15 years old at the time of the first survey (June). As teachers, we know that the development of children is being arrested year by year. Therefore, I consider junior high school students, especially those who are in the third grade in Okayasu's research, are on the equivalent level of development as the first-grade senior high school students targeted in this report. For the current study I have referenced the items used from the report by Okayasu.
The items about their cognition to their fathers and mothers were cited from the survey carried out by Tokyo Metropolitan Living Culture Bureau.26 Each item has four scale levels, and the respondents were asked to select the most appropriate frequency.
Assessment of each item was scored from 0 to 3 points for replies consisting of ‘never’, ‘rarely’, ‘sometimes’, and ‘frequently’. The score with respect to psychosomatic complaints was shown as the higher the score, the more their complaints. The scale in 30 items about psychosomatic complaints was based on a principal factor analysis with varimax rotation. In order to analyse the relationships between extracted factors and cognition to their fathers, mothers, friends, teachers and awareness of schoolwork, I conducted Pearson's product moment correlation by the sexes. The cognition score showed that the higher the score, the more their cognition was positive.
With respect to the relationship between extracted factors and the items about lifestyle habits, I conducted Pearson's product moment correlation by the sexes. For analyses, the statistical package SPSS was used (SPSS 9.05 for Windows, SPSS Co., Chicago, USA).
The number of valid answers was 168 (100% of the collection rate, 58 males and 110 females).
(1) Scale for 30 items of psychosomatic complaints.
The content validity of the 30 psychosomatic complaints was confirmed by specialists (one doctor and one psychologist). As for the surface validity, I asked five non-target students to respond to the questions to get their opinions on difficulty of expression of questions and the length of the time for responding, and they did not indicate any problems.
I studied the construct validity by principal factor analysis. The communality estimation was established by squared multiple correlation. The rotation was performed on factors with eigenvalues ≥1.0. Consequently, five factors were extracted. The five factors, Factors 1, 2, 3, 4, and 5, were named factors of depressive symptoms, physical symptoms, neurotic symptoms, digestive symptoms, and allergic symptoms, respectively. The Cronbach's alpha coefficient indicating internal consistency in each factor was 0.32–0.91. The alpha coefficient was 0.91 for 30 psychosomatic complaints (Table 1).
Because the alpha coefficient for factors of allergic symptoms was low, the three items belonging to the factors were excluded and the analyses of factors were conducted with 27 items again. Four factors were extracted as was the case for 30 items. Moreover, as for the correlation coefficients of 30 items, the three items classified into those of allergic symptoms have such small correlation with the other items that its relation was not found. Thus, the factors of allergic symptoms were excluded in the analyses, and their psychosomatic complaints were analysed with the four factors. The alpha coefficient was 0.91 for 27 items.
In the items about their cognition to their fathers, mothers, friends, and teachers, and schoolwork, the alpha coefficient was 0.69, 0.70, 0.87, 0.79, and 0.51, respectively.
(2) Comparison of psychosomatic complaints between the males and females.
The female students had significantly higher scores for depressive symptoms, physical symptoms, and neurotic symptoms, as shown in Table 2.
Table 2. Mean of the scores for the factors of psychosomatic complaints
|Depressive symptoms (0–30)||11.28 (7.65)||15.66 (7.84)||3.48***|
|Physical symptoms (0–30)||9.48 (6.29)||12.27 (6.21)||2.76**|
|Neurotic symptoms (0–15)||1.84 (2.32)||2.95 (2.71)||2.63*|
|Digestive symptoms (0–6)||1.03 (1.68)||1.20 (1.24)||0.73 n.s.|
(3) The relationship between their psychosomatic complaints and their cognition to their fathers, mothers, friends, teachers, and schoolwork.
It is concluded that male and female students who negatively recognize their fathers, mothers, teachers and schoolwork often have psychosomatic complaints (Table 3).
Table 3. Correlation between psychosomatic complaints scale score and students' cognition
|Depressive symptoms||− 0.36**||− 0.11||− 0.20||− 0.33**||− 0.47***|
|Physical symptoms||− 0.22||− 0.14||− 0.01||− 0.27*||− 0.29*|
|Neurotic symptoms||− 0.18||− 0.30*||− 0.13||− 0.14||− 0.30*|
|Digestive symptoms||− 0.04||− 0.16||− 0.09||− 0.36**||− 0.41***|
|Depressive symptoms||− 0.18||− 0.31**||− 0.12||0.07||− 0.28**|
|Physical symptoms||− 0.25*||− 0.20||− 0.01||− 0.13||− 0.06|
|Neurotic symptoms||− 0.10||− 0.17||− 0.05||− 0.22*||− 0.02|
|Digestive symptoms||− 0.05||− 0.07||− 0.20||− 0.16||− 0.05|
(4) The relationship between psychosomatic complaints and ingestion or sleep.
For the males, the correlation between the scores for various neurotic symptoms and those of meals is shown in Table 4. For the females, the correlation between the scores for various depressive symptoms and sleeping hours is shown in Table 4.
Table 4. Correlation between psychosomatic complaints scale score and students' lifestyle habits
|Depressive symptoms||0.05||0.32||− 0.15||− 0.26|
|Physical symptoms||0.09||0.22||− 0.17||− 0.18|
|Neurotic symptoms||− 0.26||0.38**||0.01||− 0.12|
|Digestive symptoms||0.01||0.04||− 0.08||− 0.22|
|Depressive symptoms||0.02||0.08||− 0.04||− 0.28**|
|Physical symptoms||0.05||0.23||− 0.04||− 0.22|
|Neurotic symptoms||− 0.07||− 0.01||0.10||− 0.01|
|Digestive symptoms||0.17||− 0.01||0.10||− 0.19|