Cross-cultural detection of depression from nonverbal behaviour

Millions of people worldwide suffer from depression. Do commonalities exist in their nonverbal behavior that would enable cross-culturally viable screening and assessment of severity? We investigated the generalisability of an approach to detect depression severity cross-culturally using video-recorded clinical interviews from Australia, the USA and Germany. The material varied in type of interview, subtypes of depression and inclusion healthy control subjects, cultural background, and recording environment. The analysis focussed on temporal features of participants' eye gaze and head pose. Several approaches to training and testing within and between datasets were evaluated. The strongest results were found for training across all datasets and testing across datasets using leave-one-subject-out cross-validation. In contrast, generalisability was attenuated when training on only one or two of the three datasets and testing on subjects from the dataset(s) not used in training. These findings highlight the importance of using training data exhibiting the expected range of variability.

I. Introduction

Clinical depression is a mood disorder with high prevalence worldwide, which can result in unbearable pain and disabling conditions that impair an individual's ability to cope with daily life. The World Health Organization (WHO) lists depression as the fourth most significant cause of suffering and disability worldwide and predicts it to be the leading cause in 2020 [1], [2]. The WHO estimates that 350 million people worldwide are affected by depression [2]. Although clinical depression is one of the most common mental disorders, it is often difficult to diagnose because it manifests itself in different ways and because clinical opinion and self-assessment are currently the only ways of diagnosis. This risks a range of subjective biases. According to the WHO [2], the barriers to effective diagnosis of depression include a lack of resources and trained health care providers. Moreover, evaluations by clinicians vary depending on their expertise and the depression screening instrument used (e.g. Quick Inventory of Depressive Symptoms-Self Report (QIDS-SR) [3], Hamilton Rating Scale for Depression (HRSD) [4], Beck Depression Inventory (BDI) [5]).