Relationship between self-rated health and depression risk among children: Promoting school–medical care cooperation for child suicide prevention

Participants

We selected schools located in seven cities in A, B, and C prefectures in Japan, each with a population of 30,000. We believe these were the most representative schools in Japan with regard to school courses, scale, student sex ratio, and academic ability. A questionnaire survey was conducted with a total of 6,421 (3,262 male, 3,159 female) students: 1,962 (1,031 male, 931 female) from four elementary schools, 2,097 (1,079 male, 1,018 female) from five junior high schools, and 2,362 (1,152 male, 1,210 female) from four senior high schools. Subsequently, responses from 5,641 students (2,824 male, 2,817 female), of whom 1,592 (830 male, 762 female) belonged to elementary schools, 1,875 (958 male, 917 female) to junior high schools, and 2,174 (1,036 male, 1,138 female) to senior high schools, who were present on the day of the survey and completed the entire questionnaire correctly, were analyzed (valid response rate: 87.9%).

Study period and procedure

A period between late November 2018 and early June 2019, when neither in-school events nor regular tests took place, was chosen for each school. The survey was conducted during a short morning homeroom session or at lunchtime by homeroom teachers and their assistants on a school-wide basis.

Study items

To assess self-rated health, the Comprehensive Survey of Living Conditions presents the following question: “What is your current health condition? Please mark the most appropriate number with a circle,” with response options of “1: Good,” “2: Relatively good,” “3: Normal,” “4: Relatively bad,” and “5: Bad.” Answers were quantified by scoring “Good” as 5 and “Bad” as 1. However, solely textual response options may not be easy for children, especially elementary school students, to understand. Therefore, upon deliberation, we created original questions by combining words and illustrations that utilized the concept of weather to facilitate understanding (Figs. 1 and 2).

[Figures 1 and 2 around here]

Additionally, considering the necessity of asking about physical health symptoms such as recurring headaches, abdominal pain, and vomiting [24–27], along with mental health symptoms, we classified these questions into two domains and presented them separately, as follows: “If your body were the weather, how would it feel?” and “If your heart were the weather, how would it feel?” (self-rated health assessment tool). We further classified the questions according to the duration of each symptom—“not persisting for two weeks” and “persisting for two weeks or longer”—based on the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition depression criteria [28], where five or more symptoms, including depressive mood or loss of interest or pleasure, persisting for two weeks or longer, are required for diagnosis. Furthermore, in the domain of self-rated physical health, we asked the children to describe the body part responsible for and the reason for their condition. In the domain of self-rated mental health, we asked them to identify the cause by circling “school,” “home,” or “other” and to describe the reason for the marked cause.

Depression assessment was based on Murata et al.’s [17] Japanese version of the Depression Self-Rating Scale for Children (DSRS-C) originally developed by Birleson [29]. The 18 statements, designed to examine students’ tendencies related to spiritlessness and depression over the past week, were rated on a three-point scale: “Most of the time” (2), “Sometimes” (1), and “Never” (0). The full score is 36, and the cutoff score is 16. Higher scores indicate more markedly depressive states. Firth and Chaplin [30] demonstrated that the DSRS-C is useful for screening for depressive states. As there are only 18 statements, the scale does not take much time to complete; therefore, there is not much of a burden on elementary and junior/senior high school students. Statements are easy to understand, with soft expressions to avoid causing mental conflict in participating children.

Ethical considerations

We visited each of the 13 schools and explained the study objective, methods, and privacy protection measures to receive their consent individually. We asked the school principals to provide parents with this explanation and seek their approval. Subsequently, we asked the homeroom teachers and assistants in charge of distributing the questionnaire to orally explain certain measures to the students to obtain their consent prior to the study. Students were informed that they would not be at any disadvantage for refusing to participate or being unable to complete the questionnaire. It was clarified that all information would be anonymized to prevent the identification of individuals; there would be no pressure on students, the teacher, assistant teacher-in-charge, or others when filling out the questionnaire; students did not need to fill out the questionnaire in front of the teacher; and the statistical processing of all survey results and their use was for this study only. Submitting a questionnaire was regarded as consent from a child. The study was approved by the Medical Ethics Committee of our institution.

Analysis

To clarify overall associations regarding self-rated health and mean DSRS-C score, we performed an ANOVA based on sex and school type. Subsequently, to clarify the relationship between self-rated health and depressive states, we calculated correlation coefficients adjusted for school type and sex.

For the questionnaire, we regarded “Normal” as a positive answer, thus dividing all answers into two choices: “Good/Relatively good/Normal” and “Relatively bad/Bad” [31]. We then divided the children’s ratings of their physical health condition as “Relatively bad/Bad” into two groups based on duration, “not persisting for two weeks” and “persisting for two weeks or longer,” and performed an ANOVA. We similarly analyzed data for the domain of self-rated mental health. We performed all analyses using SPSS ver. 26 (IBM Japan, Ltd.).

Children’s self-rated health

The results of the sex- and school type-based analysis of the self-rated physical and mental health of elementary, junior high, and senior high school students are shown in Tables 1 and 2.

The overall mean ± standard deviation score for self-rated physical health was 3.60 ± 1.06, and males had significantly higher scores than females. Sex based differences were not observed for any school type. Elementary school students had significantly higher scores than junior and senior high school students, and scores of junior high school students were significantly higher than those of senior high school students. Similarly, the overall mean ± standard deviation score for self-rated mental health was 3.65 ± 1.11, and males had significantly higher scores than females. As for sex based differences at each type of school, males had significantly higher scores than females at junior high schools. Elementary school students had significantly higher scores than junior and senior high school students, and the scores of junior high school students were significantly higher than those of senior high school students.

Depression

The total DSRS-C scores, representing depression, and the results of the sex- and school type-based analysis of responses to the DSRS-C are shown in Table 3.

The overall mean ± standard deviation DSRS-C score was 11.82 ± 6.24, and females had significantly higher scores than males. As for sex based differences for each type of school, females had significantly higher scores than males in junior high schools. Senior high school students had significantly higher scores than elementary and junior high school students.

Relationship between self-rated health and depression

Children’s depressive states may vary depending on their self-rated health levels. Therefore, to examine the relationships of self-rated physical and mental health scores with total DSRS-C score, we calculated Pearson’s and partial correlation coefficients (Table 4). The correlation coefficients in all cases were significant, ranging from 0.40 to 0.60.

DSRS-C, Depression Self-Rating Scale for Children

Effective use of the tool and the relationship between self-rated health and depression risk

To provide a basis for the effective use of the self-rated health assessment tool, we compared the three groups of children based on their physical/mental conditions together with the duration of those conditions (Favorable Health: rating their physical/mental health condition as “Good/Relatively good/Normal”; Temporarily Poor Health: “Relatively bad/Bad” + “not persisting for two weeks”; and Persistently Poor Health: “Relatively bad/Bad” + “persisting for two weeks or longer”).

In the domain of self-rated physical health, 85.3% of all children belonged to the Favorable Health group, whereas those belonging to the Temporarily and Persistently Poor Health groups accounted for 8.1% and 6.6%, respectively. There were significant differences related to school type, but no sex based differences were observed. In the domain of self-rated mental health, 85.7% of all children belonged to the Favorable Health group, whereas those belonging to the Temporarily and Persistently Poor Health groups accounted for 5.4% and 8.9%, respectively. There were significant differences related to both sex and school type (Table 5).

Next, we compared the prevalence of depression among the three groups. In the domain of self-rated physical health, the mean DSRS-C score for each group was as follows: Favorable Health: 11.11 ± 5.92, Temporarily Poor Health: 14.71 ± 6.12, and Persistently Poor Health: 17.36 ± 6.68. The Persistently Poor Health group had significantly higher DSRS-C scores than the Temporarily Poor and Favorable Health groups, while the scores for the Temporarily Poor Health group were significantly higher than those for the Favorable Health group. Similarly, in the domain of self-rated mental health, the mean DSRS-C score for each group was as follows: Favorable Health: 10.77 ± 5.61, Temporarily Poor Health: 16.50 ± 5.81, and Persistently Poor Health: 19.09 ± 6.12. The Persistently Poor Health group had significantly higher scores than the Temporarily Poor and Favorable Health groups, while the scores for the Temporarily Poor Health group were significantly higher than those for the Favorable Health group. As for the DSRS-C cutoff (16), the Persistently Poor Health group had higher self-rated physical health scores, and the Temporarily Poor Health and Persistently Poor Health groups had higher self-rated mental health scores (Tables 6 and 7).

All data are presented as mean ± SD; one-way ANOVA with post hoc Tukey test was applied for significance testing.

p value is significant at < 0.05

Variance analysis (one factor and three levels) was performed, and Tukey's method was used for multiple comparisons. All data are presented as mean ± SD; one-way ANOVA with post hoc Tukey test was applied for significance testing.

p value is significant at < 0.05

When asked about their physical health conditions, many children in the Persistently Poor Health group answered that the body part responsible was their “head” (17.7%), “abdomen, stomach, intestines” (11.8%), or “low back, shoulder, neck, whole body (25.1%).” Common reasons included: “I have abdominal pain,” “I have a headache,” “I can’t sleep,” “I have a stiff neck and shoulders,” “I often vomit,” and “I get tired easily.” The leading cause of poor mental health in this group was “school” (58.9%), followed by “home” (15.8%), and “other” (including N/A) (25.3%). The most common reasons included: “I feel tired,” “I feel gloomy,” “There are many things to worry about,” “I care about what other people think,” “Stress,” “Anxiety,” “No fun at all,” “Bullying,” and “I don’t understand what I study.” “School” (59.8%) was the leading cause in the Temporarily Poor Health group as well, followed by “home” (10.8%), and “other” (including N/A) (29.5%). There were no significant differences between these groups (Table 8).

Moreover, to assess the self-rated health screening tool, we calculated sensitivity, specificity, false positive fraction, false negative fraction, prevalence rate, positive predictive value, and negative predictive value by matching with DSRS-C cutoff values (Tables 9 and 10).

Regarding the results of self-rated physical health measurements obtained by matching with DSRS-C cutoff values, sensitivity was 14.5%, while false negative fraction was 85.5%; however, specificity was 96.4% and false positive fraction was 3.6%. Therefore, positive results indicated definite depressive states.

Regarding the results of self-rated mental health measurements obtained by matching with DSRS-C cutoff values, sensitivity was 34.1%, false negative fraction was 65.9%, specificity was 93.3%, and false positive fraction was 6.7%. Therefore, positive results indicated definite depressive states.

Relationship between children’s self-rated physical/mental health and depression

In this study, we used an original self-rated health assessment tool for children. In both domains, males’ scores were higher than females’, and self-rated health levels decreased with age. Depressive states were more prevalent among females than males, and this worsened with age.

Comparisons between the three groups of children—the Favorable, Temporarily Poor, and Persistently Poor Health groups—revealed that the majority of elementary, junior high, and senior high school students lead a physically and mentally healthy school life, as more than 85% of all children belonged to the Favorable Health group. However, approximately 15% belonged to the Temporarily or Persistently Poor Health groups, which included those with mania/manic-depressive states, as a symptom of bipolar affective disorder or cyclothymia. Thus, some children may have been experiencing poor mental and physical health.

In the domain of self-rated physical health, children belonging to the Persistently Poor Health group had DSRS-C scores higher than 16, which is the DSRS-C cutoff, and the “head” and “abdomen, stomach, intestines” were the most common body parts responsible for their poor physical health conditions. Their poor mental health may have been caused by poor physical health; however, the reverse may also be possible. Furthermore, 60% of them selected “school” as the cause of their poor mental health conditions, suggesting a significant correlation between their psychophysiological symptoms and difficult relationships with school friends, worries about academic achievement, study pressure, and conflicts with parents and teachers [24]. The presence of chronic headaches may also suggest a typical psychophysiological disorder strongly correlated with school dislike [27]. In the domain of self-rated mental health, it should be noted that not only the Persistently Poor Health group but also the Temporarily Poor Health group had scores higher than the DSRS-C cutoff of 16. Specifically, the mean DSRS-C score in the Persistently Poor Health group was 19, significantly exceeding the cutoff value and indicating the necessity of early intervention. Furthermore, as more than half of the children selected “school” as the cause of their poor condition, the possibility of schools, where children spend most of their time, causing psychophysiological and depressive symptoms owing to difficulties related to studies, conflict in interpersonal relationships, and poor adaptation to school culture, is undeniable.

Younger children are particularly subject to physical deconditioning. In this study, the reasons for poor physical health conditions such as “I can’t sleep” and “I get tired easily” suggest sleeplessness and fatigue. Sleeplessness may indicate depression symptoms and pain such as headaches and stomachaches, whereas general malaise suggests the presence of psychophysiological disorders [25]. These conditions are difficult to screen for only through self-rated mental health assessment. Therefore, when assessing children, it may be necessary to address both physical and mental health.

Effective use of the self-rated health assessment tool to promote collaboration between medical and educational organizations

When using the self-rated health assessment tool, it may be effective to focus on the Persistently Poor Health group in the domain of physical health and both the Temporarily and Persistently Poor Health groups in the domain of mental health, and provide early intervention to prevent suicide.

By matching with the DSRS-C, it was determined that both the physical and mental health assessments had high specificity and low sensitivity. Generally, screening tests with high sensitivity and specificity are desirable. Tests with high sensitivity are of particular significance to diagnoses of exclusion.

Based on our analyses, we emphasize the need for screening tests with a high degree of specificity. First, trusting, cooperative relationships between those involved in education and medical care are indispensable. Medical and educational professionals are extremely busy. Therefore, when attempting to form a seamless connection between educational and medical care, for adequate treatment to be a possibility, there should be no room for doubt about a child’s symptoms. If sensitivity of a test is high and false positives are very common, there is no guarantee that adequate treatment will be received. Moreover, even if a child receives the necessary treatment, false positives may cause those involved in medical care to lose trust in educational institutions.

Second, when connecting children from educational institutions to medical care, it is necessary to have a relationship of trust with parents. If a test with high sensitivity results in false positives and children are consequently connected to medical care, parents will lose trust in teachers. Therefore, it is considered necessary to communicate the screening test results to the concerned individual and his/her guardian with confidence, and to be very certain about the decision to connect to medical care. A survey on the mental health conditions of elementary and junior high school students revealed a gap between the results of an assessment conducted by homeroom teachers and children’s actual mental health conditions [7]. As many children selected “school” as the cause of their poor conditions in the present study, the self-rated health assessment tool may be useful for teachers to objectively identify children with an increased risk of suicide and to make a definitive decision about connecting them to medical treatment.

In addition, the tool helps children to objectively understand themselves. Conceptualization of their body/heart as the weather may help them develop objective insight into their physical and mental conditions. With a growing number of people showing signs of depression, there are currently global concerns over increased suicide risk. In such a situation, the tool may be useful not only for teachers and other people around children to recognize their physical and mental conditions but also for children to objectively understand themselves.

Limitations

Despite the abovementioned strengths, this study has some limitations. The participants were limited to students from elementary, junior high, and senior high schools in three prefectures, rather than throughout Japan. Assessment methods other than a questionnaire survey, such as interviews, could have been considered. We could also have considered the possible influence of assessment time on disorders with diurnal variations, represented by depression and orthostatic disturbance. A future challenge is to further examine methods to effectively use the self-rated health assessment tool and promote organic collaboration with external support institutions. It is especially important to promptly develop systems for appropriate and organic collaboration between educational settings and medical or welfare services.