“…PSG is often conducted in a controlled environment, such as a hospital or a specialised sleep centre. It combines a variety of modalities, including electroencephalogram, electromyography, electrooculography, and electrocardiogram, and requires a specialist to interpret (Guillodo et al, 2020;Markun & Sampat, 2020;Smits, 2021). A population study on insomnia among 1042 members of the general adult population showed that by using polysomnography, sleeping difficulties were identified in 32% of the cases, compared to 15% based on self-reports (Castro et al, 2013).…”