The Patient Health Questionnaire-9 (PHQ-9) is commonly used to screen for depressive disorder and for monitoring depressive symptoms. However, there are mixed findings regarding its factor structure (i.e., whether it has a unidimensional, two-dimensional, or bi-factor structure). Furthermore, its measurement invariance between non-clinical and clinical populations and that between patients with major depressive disorder (MDD) and MDD with comorbid anxiety disorder (AD) is unknown. Japanese adults with MDD (n = 406), MDD with AD (n = 636), and no psychiatric disorders (non-clinical population; n = 1,163) answered this questionnaire on the Internet. Confirmatory factor analyses showed that the bi-factor model had a better fit than the unidimensional and two-dimensional factor models did. The results of a multi-group confirmatory factor analysis indicated scalar invariance between the non-clinical and only MDD groups, and that between the only MDD and MDD with AD groups. In conclusion, the bi-factor model with two specific factors was supported among the non-clinical, only MDD, and MDD with AD groups. The scalar measurement invariance model was supported between the groups, which indicated the total or sub-scale scores were comparable between groups.

The 7-item Generalized Anxiety Disorder Scale (GAD-7) is commonly used to monitor anxiety symptoms. However, its factor structure has been inconsistent among competing models: unidimensional, two-dimensional, or higher order models. Additionally, it is unknown whether the scale has measurement invariance between populations with and without self-reported psychiatric diagnostic status. Participants were Japanese adults with self-reported anxiety disorder (AD; n = 479), self-reported AD and major depressive disorder (MDD; n = 314), or without self-reported psychiatric diagnostic status (self-reported non-MDD/AD; n = 654), who completed this questionnaire on the Internet. Confirmatory factor analyses showed the higher order model had similar fit indices to the unidimensional and two-dimensional factor models. For the higher order model of GAD-7, metric invariance was supported between the self-reported non-MDD/AD and self-reported AD status groups, and scalar invariance was supported between the self-reported AD status and self-reported AD with MDD status groups. Moreover, convergent and discriminant validity were consistent with previous findings in Western cultures. These results suggest that factor loadings are equivalent and the construct has the same meaning between the self-reported non-MDD/AD and self-reported AD status groups, and the total or sub-scale scores were comparable between self-reported AD status and self-reported AD with MDD status groups. The major limitation of this study is that the participants’ diagnoses were self-reported, not confirmed by clinical structured interview. Further studies that incorporate clinical structured interviews are needed.

The aim of this study is to examine the association between maternal adverse childhood experiences (ACEs) and mental health problems in adolescent offspring. Data were obtained from the population-based Kochi Child Health Impact of Living Difficulty (K-CHILD) study in 2016, and participants were 10,810 children in the fifth grade (3,144 pairs), eighth grade (3,497 pairs), and eleventh grade (4,169 pairs) living in Kochi Prefecture, Japan. Mothers of participating children were asked about their ACEs, childhood social economic status, current mental and physical health, current social economic status, positive parenting behaviors, child maltreatment, marital status, and child behavior problems using the Strength and Difficulty Questionnaire. Children reported their depressive symptoms using the Depression Self-Rating Scale. Children of mothers with a larger number of ACEs showed higher levels of behavior problems (p for trend <.001) and depressive symptoms (p for trend <.001), adjusting for potential confounders. In particular, maternal psychological distress mediated the association between maternal ACEs and child mental health. The adverse effects of maternal ACEs may have a direct intergenerational impact on behavior problems and depressive symptoms in adolescent offspring. Further studies to elucidate possible mediators are needed.

Childhood maltreatment history has known relationships with various mental and physical diseases; however, little is known about its association with premenstrual syndrome (PMS). In this study, we investigated the association between childhood maltreatment history and PMS among young women in Japan. In a Japanese city, we approached 3815 women aged 10–60 years who visited a gynecology clinic and one general practice clinic. A questionnaire on childhood maltreatment history and PMS was administered to them. We observed that women with histories of childhood maltreatment demonstrated a significantly increased risk of PMS compared with those without such histories (odds ratio: 1.47, 95% confidence interval: 1.20–1.81). Particularly, women with childhood physical or emotional abuse demonstrated a stronger association with PMS, whereas other forms of childhood maltreatment (emotional neglect, witnessing of intimate-partner violence, or sexual abuse) were not associated with PMS. Our results illustrate that childhood maltreatment may be a risk factor for PMS.