A new study suggests that the mental health impact of Covid-19 on the general population may not have been as significant as previously thought. Researchers at McGill University in Canada reviewed 137 studies from around the world and found minimal changes in mental health symptoms among most people during the pandemic. However, experts have disputed this, pointing out that the impact on specific groups such as children, women, and people with low incomes or pre-existing mental health problems cannot be overlooked.

The senior author of the study, Brett Thombs, said that some of the public narrative around the mental health impacts of Covid-19 was based on poor-quality studies and anecdotes that became self-fulfilling prophecies. He added that there was a need for more rigorous science in this area. The researchers at McGill found their findings consistent with the largest study on suicide during the pandemic, which found no increase, and applied to most groups, including different ages, sexes, genders, and those with pre-existing conditions.

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However, the researchers acknowledged that women had experienced worsening anxiety, depression, or general mental health symptoms during the pandemic, possibly due to juggling more family responsibilities, working in health or social care, or domestic abuse. The team also noted that depression symptoms had worsened by “minimal to small amounts” for older adults, university students, people who self-identified as belonging to a sexual or gender minority group, and parents.

The study’s authors concluded that governments and health agencies need to produce better quality and more timely mental health data to better target resources and that governments should continue to properly fund services, especially for the groups worst affected by the pandemic. However, other research has suggested that the mental health impact of the pandemic has been much more severe.

Commenting on the study, Gemma Knowles from the Centre for Society and Mental Health at King’s College London said that the findings echoed other research showing that some people’s mental health improved and others’ deteriorated during the pandemic, which could mean no overall increase. She added that the study risks obscuring important effects among the most affected and disadvantaged groups and, from that, obscuring possible widening of inequalities in mental distress that occurred because of the pandemic.