A total of 1,041 Japanese university students (540 females) from five Tokyo metropolitan area universities participated in this study (Nihon University = 222, Ochanomizu University = 42, Tokyo Seitoku College = 313, Tokyo University of Agriculture = 365, Rissho University = 99). These universities were all of available universities for the authors at the date of survey.
Procedure and ethics
This study was approved by the Institutional Review Board of the National Center of Neurology and Psychiatry, Japan (Approved Number: A2010-028). A packet of anonymous questionnaires was administered after lectures at the universities. Before administering the survey, one of the authors or the instructor explained the purpose of the study and addressed any ethical issues. We also distributed documents describing the purpose of the study and related ethical issues before distributing the questionnaires. Participants gave informed consent by completing and submitting the questionnaires. Time One and Time Two data were matched by referring to the free key words written by each participant. No reward or course credit was given in exchange for participating in this study, which took approximately 20 minutes to complete.
The survey was conducted at two time points separated by one month. The participants from Nihon University and Ochanomizu University participated in the Time One but not the Time Two survey; answered demographic information questions; and completed the ASQ, the AAQ-II, the TAS, and the Brief COPE. Some participants from Tokyo Seitoku University, Tokyo University of Agriculture, and Rissho University participated in both, the Time One and Time Two surveys; other participated only in Time One or Time Two surveys. Participants answered demographic information questions, completed the ASQ (Time One, & Time Two), the ERQ (Time One), the SCS (Time One), the Rumination-Reflection Scale-shorter version (Time Two), and the Hospital Anxiety and Depression Scale (HADS) (Time Two).
The original validation study of the ASQ examined the relationship of the ASQ with other emotion regulation measures, such as the Emotion Regulation Questionnaire (ERQ) , Berkeley Expressive Questionnaire , Acceptance and Action Questionnaire-II (AAQ-II , Toronto Alexithymia Scale (TAS; , Brief COPE (, and Difficulties in Emotion Regulation Scale . Among them, we used the scales available in the Japanese language (i.e., ERQ, AAQ-II, TAS, Brief COPE) and Rumination and Reflection Questionnaire (Trapnel PD: RRQ shorter version, http://www.paultrapnell.com/measures/RRQ.pdf) that seemed conceptually related to ASQ.
The ASQ  is a 20-item scale, measured on a 5-point Likert scale. Factor analyses using two different samples of US university students showed three factors: concealing, adjusting, and tolerating. The internal consistency values of the ASQ subscales in the US samples were .84, .80 − .82, and .66 − .68 for concealing, adjusting, and tolerating, respectively. The study demonstrated the convergent and discriminant validity in terms of the patterns of relations between existing instruments that measured similar constructs.
We used a standard back translation procedure  to translate the ASQ into Japanese. First, one of the Japanese authors translated the ASQ into Japanese. Second, a bilingual Japanese clinical psychologist, who has a master’s degree in psychology and did not know the original ASQ items, back-translated the Japanese version into English. Third, one of the original authors of the ASQ (SGH) checked the back-translated items for concordance of meaning and expression, and provided comments that specified the minor adjustments and modifications that had to be made to the wording of the questionnaire items. Fourth, the Japanese author modified some items and the Japanese bilingual psychotherapist again back-translated the items. Finally, the original author confirmed accuracy of the items.
The ERQ  is a 10-item scale used to assess two types of emotion regulation: reappraisal and suppression. The items are scored on a 5-point Likert scale. Internal consistencies of the Japanese version were indexed by the Cronbach’s alpha values and were .77 and .78 for reappraisal and suppression, respectively . Confirmatory factor analysis revealed that the Japanese version had a two-factor structure with weak positive relationship between reappraisal and suppression .
The AAQ-II  is a 10-item scale used to assess emotional flexibility or experiential avoidance. Items are scored on a 5-point Likert scale. Sufficient internal consistency (Cronbach’s alpha = .86) and two week test-retest correlation (r = .62, p < .01) was reported in a study that used Japanese university students . The authors also found evidence of convergent validity in terms of the instrument’s correlations with the trait subscale of the State-Trait Anxiety Inventory (r = -.72, p < .01), Zung Self-Reporting Depression Scale (r = -.50, p < .01), and White Bear Suppression Inventory (r = .62, p < .01). Higher questionnaire scores indicate higher emotional flexibility and lower emotional avoidance.
The TAS  is a 20-item scale used to measure three aspects of alexithymia: difficulty identifying feelings, difficulty describing feelings, and externally oriented thinking. The reliability and validity of the TAS has been demonstrated with a sample of Japanese participants . Confirmatory factor analysis confirmed a three-factor structure with a Japanese sample. The Cronbach’s alpha values when used with a sample of Japanese university students were .85, .72, and .58 for difficulty identifying feelings, difficulty describing feelings, and externally oriented thinking, respectively.
Rumination and reflection questionnaire-shorter version
The Rumination and Reflection Questionnaire-Shorter Version (RRQ-S) is an 8-item measure, a short version of the original scale , used to assess rumination and reflection. The reliability and validity of the Japanese original version was confirmed . The internal consistency in this study ranged from .68 (for reflection) to .78 (for rumination).
The Brief COPE , an abbreviated version of the original scale , is a 28-item measure used to assess 14 types of stress-coping. Each subscale consists of two items, and the internal consistency (Cronbach’s alpha = .46–.80) of the subscales has been reported previously . Although some of the subscales could be improved, a previous confirmatory factor analysis with a sample of Japanese participants showed an acceptable fit with the data .
The SCS  is a 31-item measure of two aspects of self-construal: interdependent self-construal and independent self-construal. The Japanese version of the SCS was provided by the original author. It is assumed that people in Eastern cultures tend to exhibit interdependent self-construal, whereas those in Western cultures tend to exhibit independent self-construal. The index of internal consistency in this study was .78 for both interdependent and independent self-construal.
The HADS  is a 14-item scale used to assess the severity of anxiety and depression. A previous confirmatory factor analysis, which confirmed the two-factor structure with a sample of Japanese participants, suggested a sufficient fit with the data. The reliability and validity of the Japanese version has been reported previously . The internal consistency coefficients for the Japanese version were .76 and .81 for depression and anxiety, respectively .
First, we used the data obtained at Time One to conduct an exploratory factor analyses (EFA) to examine the factor structure of the ASQ. The original validation study  employed principal components extraction with varimax rotation. We used this method to determine whether the original three-factor structure could be replicated with the data from the present study. The number of appropriate factors was determined by examining the Eigen values, the scree test, and the interpretability of the factors. After the first EFA, we excluded the items that cross-loaded onto more than one factor (loadings > .35), and repeated the same EFA without these items. This factor analysis procedure was based on the recommendation provided by Costello and Osborne . Next, the data obtained at Time Two were used in a confirmatory factor analysis to determine and cross-validate the factor structure in this sample of Japanese participants. Goodness-of-fit indices, including the root mean square error of approximation (RMSEA), the Comparative Fit Index (CFI), and the Tucker–Lewis Index (TLI) were examined to determine how well the model fit the data (D’Avanzato et al.). Standardized factor loadings were used to assess the appropriateness of the measurement for the latent factor.
The reliability of the ASQ was determined by calculating Cronbach’s alpha and test-retest correlation coefficients. Means and standard deviations of the ASQ subscales were calculated for the scores obtained at Time One and Two. The correlations between the subscales of the ASQ and various measures (i.e., the ERQ, AAQ-II, TAS, COPE, RRQ-S, and SCS) were calculated to examine the ASQ’s convergent and discriminant validity. Then, we performed multiple regression analyses to examine the influence of the subscales of the ASQ and ERQ at Time one on depression and anxiety at Time two (i.e., one month after). We included the ERQ in the regression analysis because the majority of the studies of emotion regulation have been based on the process model of emotion regulation proposed by Gross  and used the ERQ. All p values were two-tailed. Statistical analyses were conducted using PASW Statistics for Windows, Version 18.0 (Chicago; SPSS Inc) and Amos 18.0 .