The shortened version of the Adolescent Stress Questionnaire (ASQ-S; Sweden): a validation study in United Kingdom adolescents

Introduction

The deleterious effect of stress in adolescence has been well documented (1-3), and for that reason continued scrutiny of the measurement of stress in this developmental period is essential to public health. One measurement tool with considerable promise is the Adolescent Stress Questionnaire (ASQ; [4]). Results of variable-centred studies on the structural validity of ASQ scores have been unequivocal: the ASQ yields multivariate scores structured by the domain-specificity of stressors in adolescence (e.g.4-6). Specifically, the structural validity of ASQ scores has been substantiated by confirmatory factor analysis (CFA), intercorrelations that indicated related but distinctly different constructs, and convergent validity analyses. Nevertheless, on-going inquiries into psychometric properties of ASQ scores warrant our attention.

Byrne et al. (4) developed the 56-item Adolescent Stress Questionnaire as an index of stress consisting of items forming 10 different stress components or domains. The specific domains examined are the stress of: home life; school attendance; school performance; peer pressure; emerging adult responsibility; school/leisure conflict; romantic relationships; teacher interaction; future uncertainty; and financial pressures. Psychometric studies examining the properties of ASQ scores have reported mixed results with some supportive (4,7), and others reporting problems with both structural validity and internal consistency (8), test-retest reliability (9), and problematic factor loadings (6). Although (6) reported adequate fit indices among Northern Irish adolescents (CFI = 0.95; RMSEA = 0.08), these authors also reported concerns about the reliability (a= 0.50) and validity of ‘emerging adult responsibility’ scores specifically.

One drawback of using the ASQ is its length, particularly in studies where larger batteries of questionnaires are required to be administered. A shorter version of the ASQ might also be useful for mental health professionals who engage in screening adolescents in schools and other large agencies, such as the juvenile justice system. Accordingly, a number of researchers have proposed short versions of the ASQ, and results of these studies were in keeping with studies on the full version (10,11). One such abbreviated version of the ASQ was recently piloted in Sweden using a Swedish translation (11). Results of this study (11) indicated valid and reliable ASQ-S scores. In the present study, we aimed to use the same ASQ items selected therein (11), but retain the English version in a study among adolescents in Northern Ireland. This approach allowed us to determine whether or not the psychometrics of Anniko et al. (11) proposed model were sensitive to translation in language and, or, difference in European culture. The data we used were data previously used to examine the properties of the full ASQ (6).

The specific purpose of the present study is to examine the model fit, internal consistency, and construct validity of the ASQ-S (11). Specifically, ASQ-S scores were subjected to confirmatory factor analysis (CFA), and invariance testing by gender, stage of school of participants (junior versus middle high school), and type of school attended by participants (grammar [a more academic setting] versus secondary [a more vocational setting]). Further, construct validity was assessed by examining correlations between ASQ-S scores, and scores on four self-concept measures. Finally, construct validity included an analysis of the relationship between alcohol use scores and scores on ASQ-S domains, adjusted for other variables of interest.

Methods

Measures

The 27-items of the ASQ-S (11) were used for analyses. The scale measures stress in nine of the original ten ASQ domains: home life, school attendance, school performance, romantic relationships, peer pressure, school-leisure conflict, teacher interaction, future uncertainty, and finance. For each item, participants are asked, ‘How stressful do you find’ (e.g. going to school). Participants rate the level of stress experienced on a five-point Likert-type scale (1 = not stressful at all to 5 = very stressful).

The Adolescent Alcohol Involvement Scale (AAIS): the AAIS (12) is a 14-item self-report screening measure for alcohol abuse in adolescents. It is a compilation of previously verified indicators of alcohol misuse. It functions as a research tool, which helps identify adolescents whose alcohol use impacts adversely on psychological functioning, social relations, and/or family life. Questions are answered on a scale allowing for a highest possible score of 79. The psychometric properties of the AAIS have been demonstrated to be acceptable (13).

The Rosenberg Self-Esteem Scale (RSES; 14) is a 10-item self-report measure of global self-esteem. It consists of 10 statements related to overall feelings of self-worth or self-acceptance. The scale has demonstrated good reliability and validity across a large number of different sample groups (15). The RSES has been validated for use with substance users and other clinical groups, and is regularly used in treatment outcome studies. The scale has been validated for use with both male and female adolescent, adult and elderly populations (16).

The Self-Efficacy Questionnaire for Children (SEQ-C; 17) contains 21 items assessing three domains of self-efficacy: (a) academic self-efficacy; (b) emotional self-efficacy; and (c) social self-efficacy. Each subscale consists of seven items, and respondents rate their competence in each self-efficacy domain on a five-point Likert scale (1 = not at all; 5 = very well). SEQ-C subscale scores have been found to be structurally valid and internally consistent (a< 0.80) in Dutch-speaking, Belgian-speaking, and English-speaking populations (17,18).

Consent and procedure

Each participating school was supplied with parental consent forms. A form of ‘opt out’ consent was approved so that parents received detailed information on the study and were only required to respond if they were unhappy about their child’s participation. On the day of the study, each participating pupil was also asked to give their own informed consent, indicating their willingness to take part. Data were gathered under examination-like conditions with all participants from a given school completing the questionnaires simultaneously. Participants were issued with a set of response sheets, and all questionnaires were administered verbally by the researcher, allowing pupils with literacy difficulties to take part and also to help maximise the number of fully completed response sheets. Data collection took approximately 30 min in each school.

Statistical analyses

Confirmatory factor analyses (CFA) were performed using Mplus (version 8; 19). All additional analyses were conducted using SPSS v23. A number of statistical recommendations were used to determine model fit: (a) CFI ≥ 0.90, (b) TLI ≥ 0.90, (c) RMSEA =0.05 (good) to 0.08 (acceptable), and (d) SRMR ≤ 0.08 (20-23). Measurement invariance was determined by reductions in the comparative fit indexes across increasingly restrictive models: ΔCFI ≤ 0.01 and ΔTLI ≤ 0.02 (24). Invariance was tested by factor structure (configural), factor loadings (metric), and indicator/item intercepts (scalar). To aid the interpretation of variance explained we were guided by Ferguson’s (25) recommendations for ‘practical’ effect sizes, where 0.20 is the minimal value for interpretation, and 0.50 and 0.80 demark moderate and strong effects, respectively, forβand correlation coefficients (r). Ferguson (2009) suggested that for Hedge’sg, values of 0.41, 1.15, and 2.70 demark small, moderate, and strong effects, respectively.

Results

Of the 610 completed questionnaires, 238 (39%) were completed by males, 337 (55.2%) were completed by attendees of Grammar schools, and 361 (59.2%) were completed by pupils in Junior High school. CFA results in Tables1to3provide summaries of the fit indices for a baseline model as well as tests of gender, school stage, and school-type invariance. Results showed that ASQ-S scores fit the models well (total sample:χ^2s-b(288) = 751.60, CFI = 0.958, TLI = 0.948, SRMR = 0.040, RMSEA = 0.051 [90% CI = 0.047, 0.056]), and that scores were gender, school-type (i.e. Grammar or Secondary), and age groups (i.e. Junior versus Middle High school) invariant. Table4displays the results of independent samplest-tests for gender and stress domains for both the ASQ-S, and the corresponding nine factors from the full ASQ, as well as internal consistency (Cronbach’sa), and mean inter-item correlations for each stress factor. In keeping with the stress literature, females scored significantly higher on most stress domains than males. However, none of the Hedge’sgvalues for the ASQ-S scores reached the recommended practical effect size (g< 0.41). Regarding the full ASQ comparisons, there was only one Hedge’sgvalue that attained the recommended minimal effect size, and that was for the stress of peer pressure. Further, theavalues for the ASQ-S suggest that stress domain scores were broadly internally consistent, although four did fail to achieve a value of 0.7, albeit by a small margin. In contrast, theavalues for all but one of the full ASQ factors were all < 0.70. Mean inter-item correlations pointed to satisfactory internal consistency for both scale versions.