Validation of Hospital Anxiety and Depression Scale in an Indonesian population: a scale adaptation study

Objective: This study aims to adapt the English-language Hospital Anxiety and Depression Scale (HADS) to the Indonesian language and evaluate the validity and reliability of the adapted version (ie, HADS-Indonesia).

Design: A cross-sectional study was conducted between June and November 2018. First, a translation and back-translation process was conducted by a committee consisting of the researchers, a psychiatrist, a methodology consultant and two translators. Face and convergent validity and test-retest reliability evaluations were conducted. Next, structural validity and internal consistency analyses were performed. An intraclass correlation coefficient (ICC) test evaluated the scale's test-retest reliability. A Spearman's rank correlation coefficient was calculated to evaluate the correlation between HADS-Indonesia and Zung's Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS) for convergent validity evidence. Next, a structural validity analysis using exploratory factor analysis (EFA) and an internal consistency evaluation based on Cronbach's alpha was conducted.

Setting: This study was conducted in three villages in Jatinangor subdistrict, Sumedang Regency, West Java province, Indonesia; the villages were chosen based on their profiles.

Participants: A total of 200 participants (male: n=91, 45.50% and female: n=109, 54.50%), with a mean age of 42.41 (14.25) years, were enrolled in this study using a convenience sampling method. The inclusion criteria were age ≥18 years old with basic Indonesian language literacy.

Results: The overall HADS-Indonesia's ICC value was 0.98. There was a significant positive correlation between HADS-Indonesia's anxiety subscale and Zung's SAS (r_s=0.45, p=0.030) and between the depression subscale of HADS-Indonesia and Zung's SDS (r_s=0.58, p<0.001). The Kaiser-Meyer-Olkin statistics (KMO) (KMO=0.89) and Bartlett's test of sphericity (χ²(91, N=200)=1052.38, p<0.001)) indicated an adequate number of samples for EFA. All items' commonality was >0.40 and the average inter-item correlation was 0.36. EFA yielded a 2-factor solution explaining 50.80% (40.40%+10.40%) of the total variance. All items from the original HADS were retained, including its original subscales. The adapted HADS-Anxiety subscale consisted of seven items (alpha=0.85), and the HADS-Depression subscale consisted of seven items (alpha=0.80).

Conclusions: HADS-Indonesia is a valid and reliable instrument for use in the general population of Indonesia. However, further studies are warranted to provide more sophisticated validity and reliability evidence.