The Generalised Anxiety Disorder-7 (GAD-7) is a self-report scale used to assess general anxiety symptoms. Although the GAD-7 has been found to be a valid scale among adults, studies examining its psychometric properties among adolescents in high-income countries are notably limited and particularly non-existent in low- and middle-income countries. The current study addresses this lacuna by investigating the factorial validity, construct validity, internal consistency and discriminant accuracy of the GAD-7. Data were collected from 553 adolescents (boys = 231; average age = 16.85) recruited from a senior high school in Ghana, a sub-Saharan African country, using cross-sectional self-report methodology. The result supports a unidimensional structure of the GAD-7 that was invariant across gender. The GAD-7 correlates significantly with measures of anxiety, suicidal tendencies and mental well-being, suggesting construct validity. The internal consistency of the GAD-7, based on the mean inter-item correlation value of 0.24 and Cronbach’s
Adolescents are highly prone to developing a range of mental health problems, including generalised anxiety disorder (GAD) which is characterised by excessive, uncontrollable, irrational anxiety and worry (APA,
The foregoing notwithstanding, many adolescents with GAD, particularly in low- and middle-income countries (LMICs), are often undetected and untreated (Kroenke, Spitzer, Williams, Monahan, & Löwe,
Valid, reliable and easy-to-administer screening tests could help detect individuals at risk of GAD for early intervention, as well as for large-scale epidemiological studies on the prevalence, risk factors and protective factors of GAD. The Generalised Anxiety Disorder-7 (GAD-7) scale is a 7-item easy to administer tool developed to screen for probable cases of GAD based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria (Spitzer, Kroenke, Williams, & Löwe,
However, there are questions regarding the utility of the GAD-7 when administered on adolescent samples, given that studies investigating the psychometric properties of the GAD-7 among adolescents are emerging. To the best of our knowledge, only Tiirikainen et al. (
Cultural context significantly shapes behaviour, including how people feel, think and interact socially, as well as what constitute distress and the threshold for distress (Moleiro,
Because the psychometric properties of Western-based measures could be altered substantially when administered in SSA (Adjorlolo, Abdul-Nasiru, Chan, & Bentum Jr,
Consequently, the current study was designed to investigate the psychometric properties of the GAD among adolescents in Ghana to contribute to the emerging (cross-cultural) literature regarding the application of the GAD-7 in adolescents. In this regard, the study first and foremost examined the factorial validity of the GAD-7 and further determined whether the factorial validity is the same for boys and girls (i.e. invariant across gender). Gender invariance analysis examines the extent of similarity on the endorsement of the GAD-7 items for boys and girls, thereby helping to ensure that the GAD-7 scores are not biased (i.e. under or overestimated) for one group (Steinmetz, Schmidt, Tina-Booh, Wieczorek, & Schwartz,
The total student population at the time of data collection was 650. Of the 600 questionnaires administered, 555 were returned, representing a response rate of 92.5%. Two substantially uncompleted questionnaires were subsequently excluded.
Ghana’s educational system operates on a 6-3-3-4 system (i.e. primary school – 6 years, junior high school – 3 years, senior high school – 3 years and university bachelor’s degree – 4 years). The school was selected using a multi-stage sampling technique, involving a random selection of Eastern region out of the 10 regions in Ghana. This was followed by a random selection of a district in the region and one senior high school in the district. Information relating to the various schools in the selected district was obtained from the Ghana Education Service. English is the official language of instruction at the various levels of education (Adjorlolo,
A self-report methodology using a cross-sectional survey design was employed to gather data from senior high school students recruited from a school in the Eastern region of Ghana. A questionnaire consisting of a demographics section, the GAD-7, PHQ, WHO-5 and SBQ-R was used.
Generalised Anxiety Disorder-7 items are rated on a 4-point Likert scale, ranging from 0 (not at all) to 3 (nearly always). The seven items are summed to generate a total score that ranges from 0 to 20 in the present study. Higher scores indicate more severe symptoms of GAD.
Data were collected from the students in their respective classes. In each class, the research team briefed the participants on the purpose of the study and their responsibilities as participants. They were encouraged to ask questions to allay any fear and anxiety pertaining to participating in the study. Ethical issues, particularly those relating to confidentiality, anonymity and withdrawal from the study without being penalised, were communicated to the participants and ensured. To maintain anonymity, for instance, the questionnaires were devoid of identifying information of the participants such as name and student numbers. The participants were also informed that their responses will be treated strictly confidentially, and that they can withdraw from the study anytime without being penalised, or the research team can terminate their participation without their explicit consent. Those expressing interest and willing to participate in the study were handed a pack of questionnaires described previously. The questionnaires were handed over to the research team in each class upon competition. Data were collected from the second- and third-year students because the first-year students were yet to commence school at the time of data collection.
Missing data analysis revealed that less than 5% of cases have data points missing on the SBQ-R (2.4% – 3.1%), PHQ (2% – 3.3%), GAD-7 (1.3% – 2.7%) and WHO-5 (1.3% – 2.4%). Further analyses revealed that data were missing completely at random (Little’s chi-square > 0.05). Consequently, the missing data point was imputed using the expectation-maximisation algorithm (Adjorlolo & Watt,
Evidence of gender invariance was evaluated using the difference in comparative fit index (CFI; ΔCFI) and chi-square (
Zero-order correlations with measures of anxiety, mental well-being and suicidal tendencies were performed to examine construct validity of GAD-7, whereas internal consistency was investigated using Cronbach’s alpha (
The Ethics Committee for Humanities of the University of Ghana granted ethical approval for the study (Ethical clearance number: ECH 165/17-18). The school management granted institutional permission for the study.
Participants endorsing the highest response options on the items of the various measures were designated as high risk. Using this criterion, 4.2% (
The results of the factorial validity and gender invariance analyses of the GAD-7 are summarised in
Fit statistics for the Generalised Anxiety Disorder-7 scale in adolescents.
Model/fit indices | df | AGFI | TLI | CFI | RMSEA | D |
df | ΔCFI | ||
---|---|---|---|---|---|---|---|---|---|---|
Full sample | 22.79 | 14 | 1.63 | 0.98 | 0.97 | 0.98 | 0.03 | - | - | - |
Boys subsample | 18.52 | 14 | 1.32 | 0.96 | 0.97 | 0.98 | 0.04 | - | - | - |
Girls subsample | 19.13 | 14 | 1.37 | 0.96 | 0.96 | 0.98 | 0.03 | - | - | - |
Gender invariance | - | |||||||||
Unconstrained | 37.65 | 28 | 1.35 | 0.96 | 0.97 | 0.98 | 0.03 | - | - | - |
Constrained 1 | 44.70 | 34 | 1.32 | 0.96 | 0.97 | 0.98 | 0.02 | 7.05 |
6 | −0.002 |
Constrained 2 | 45.51 | 35 | 1.30 | 0.96 | 0.97 | 0.98 | 0.02 | 0.81 |
1 | 0.000 |
Constrained 3 | 52.33 | 42 | 1.25 | 0.97 | 0.98 | 0.98 | 0.02 | 6.82 |
7 | 0.001 |
Unconstrained = parameters freely estimated; Constrained 1 = factor loadings constrained; Constrained 2 = Factor variance constrained; Constrained 4 = Error variances constrained.
, not significant; df, degrees of freedom AGFI, adjusted goodness of fit index; TLI, Tucker–Lewis index; CFI, comparative fit index; RMSEA, root mean square error of approximation.
Characteristics of Generalised Anxiety Disorder-7 scale items (boys = 231, girls = 322).
No. | Scale item | Full sample |
Boys subsample |
Girls subsample |
|||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
M | s.d. | CIC | FL | M | s.d. | CIC | FL | M | s.d. | CIC | FL | ||
1 | Feeling nervous, anxious or on edge | 0.69 | 0.95 | 0.37 | 0.45 | 0.61 | 0.91 | 0.42 | 0.49 | 0.75 | 0.99 | 0.33 | 0.40 |
2 | Not being able to stop or control worrying | 0.95 | 1.00 | 0.43 | 0.54 | 0.86 | 1.00 | 0.46 | 0.56 | 1.00 | 0.99 | 0.41 | 0.52 |
3 | Worrying too much about different thing | 1.20 | 1.00 | 0.41 | 0.52 | 1.10 | 1.00 | 0.46 | 0.57 | 1.10 | 1.00 | 0.38 | 0.47 |
4 | Trouble relaxing | 0.63 | 0.93 | 0.33 | 0.41 | 0.62 | 0.92 | 0.32 | 0.38 | 0.64 | 0.94 | 0.34 | 0.44 |
5 | Being so restless that it is hard to sit at one place | 0.75 | 0.97 | 0.31 | 0.37 | 0.87 | 1.00 | 0.40 | 0.48 | 0.67 | 0.92 | 0.26 | 0.32 |
6 | Becoming easily annoyed or irritable | 0.94 | 1.10 | 0.44 | 0.55 | 0.90 | 1.00 | 0.50 | 0.60 | 0.97 | 1.10 | 0.40 | 0.50 |
7 | Feeling afraid as if something terrible or bad might happen | 1.10 | 1.10 | 0.45 | 0.56 | 0.95 | 1.10 | 0.42 | 0.51 | 1.20 | 1.10 | 0.47 | 0.61 |
M, mean; s.d., standard deviation; CIC, corrected item-total correlation; FL, factor loadings.
The GAD-7 correlated significantly and positively with measures of depression (
Likewise, the internal consistency of the GAD-7 for the full sample, based on the Cronbach’s alpha (
The GAD-7 significantly discriminated between participants designated as high and low or no risk for depression (AUC = 0.70;
The study primarily investigated the psychometric properties of the GAD-7 among adolescents in Ghana. In keeping with the findings of earlier multi-site, adult-based studies (Ito et al.,
The GAD-7 items loaded significantly onto the unidimensional factor structure, with all the factor loadings exceeding the conventional value of 0.30 (Nunnally,
Moreover, although the Cronbach’s alpha of the GAD-7 was comparatively low (i.e. 0.69), the MIC values, which are largely independent of the number of the item, are all in the recommended ranges (i.e. 0.15–0.50) to be considered adequate (Clark & Watson,
Firstly, the study did not include a gold standard measure of GAD, thereby making it impossible to assess the diagnostic properties (e.g. sensitivity and specificity) of the GAD-7 for GAD, in addition to depression and suicidal tendencies. The use of self-report measures provides no mechanism to verify the accuracy of the participants’ responses. Thus, inaccurate responses (underreporting or over-reporting) are possibilities. The generalisability of the study findings to adolescents with dissimilar background characteristics (e.g. those out of school) may be limited. Again, using a clinical sample would have provided an added layer of validity, and therefore it would be useful in future studies to examine adolescents diagnosed with GAD. Future studies addressing the limitations noted here will help to further illuminate the psychometric appropriateness and utility of the GAD-7 in adolescents in Ghana and other LMICs.
The results suggest that the GAD-7 is a reliable and valid measure to screen and identify adolescents at risk of GAD in Ghana, an SSA state. The findings have contributed to the repertoire of the cross-cultural literature on the assessment of psychopathologies or mental disorders. While the influence of cultural factors on psychopathological behaviours should not be discounted, it is equally important to acknowledge that measures developed to assess behaviours that supposedly have roots in Western, individualistic cultures could prove useful in non-Western, collectivists’ cultures.
The author declares that no competing interests exist.
I declare that I am the sole author of this research article.
This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.
Data is available upon request from the author.
The views expressed in this article are the author’s own and not the official position of his institution.