To what extent does severity of loneliness vary among different mental health diagnostic groups: A cross-sectional study.

The study was cross-sectional, so it cannot show whether loneliness caused discrimination, stigma, or diagnosis differences, or the other way round. Participants were recruited from only two London NHS trusts, so the results may not apply to other areas. Participants were adults already receiving secondary mental health care and had at least one previous hospital admission or community crisis care, so it may not apply to people treated only in primary care or first-contact services. Some people who were referred did not participate, so volunteer bias may have affected who was included. The diagnostic groups were broad, so differences within psychosis, common mental disorders, or personality disorder subtypes were not examined. Social isolation was measured with only two items, which may not capture the complexity of social networks. The loneliness scale was developed in a general population sample and may not be ideal for people with severe mental illness.

The authors declared no conflict of interest. The parent SInQUE study is described as nationally funded, but the paper does not name the funder.

Do not conclude that reducing discrimination or stigma will lower loneliness. This study shows an association at one time point, not a treatment effect.