Long COVID can affect adults, young people, and children, and now for the first time, in a landmark study accepted for publication in the Archives of Disease in Childhood, formal agreement has been made on a research definition for post–acute COVID-19, or “long COVID” as it is commonly known, in children and young people.
The researchers charged themselves with a single objective – to derive a research definition for long COVID (post–acute COVID-19) in children and young people to allow comparisons between research studies. Specifically, so studies on prevalence, course, and outcome of long COVID in this age group can be reliably compared, because to date there has been no consensus. In fact, the authors pointed out how the “slew of definitions” currently used all differ in number, type, and duration of symptoms, which hampers research efforts. In addition, the lack of definition consensus has contributed to very wide reported variations in the estimated prevalence of long COVID in children of 1%-51%, with the authors saying that a “consistently applied definition of long COVID will help reduce the variability of prevalence estimates.”
Statements sequentially whittled down
“Using robust consensus methodology,” the authors said, “we derived a research definition for long COVID in children and young people.”
To achieve the definition consensus, a three-phase online Delphi process was used, followed by a virtual consensus meeting. The 123 participants registered to take part in the study included 23 people (19%) in a lived experience panel, 50 (42%) in the researcher or researcher/service delivery combined panel and 47 (39%) in the service delivery panel. Of 120 registered participants, 105 (88%) completed phase 1, 86 eligible participants (82% of those completing phase 1) completed phase 2 and 77 eligible participants (90% of those completing phase 2) completed phase 3. Seventeen participants attended and voted at the consensus meeting – 4 (23%) from the service delivery panel, 11 (65%) from the researcher panel, and 2 (12%) from the lived experience panel.
Presented with 49 statements in each phase, participants scored these from 1-9 based on how important they were perceived to be with regards inclusion in the research definition of long COVID in children and young people. Having been sequentially whittled down in three phases, 10 statements were discussed at the consensus meeting, and a panel of eight 11- to 17-year-olds affected by long COVID also reviewed the statements to reach a final agreement.
Five of the statements were agreed to be included in the definition, which stated that long COVID in children and young people is a condition in which a child or young person has symptoms (at least one of which is a physical symptom) that have continued or developed after a diagnosis of COVID-19 (confirmed with one or more positive COVID tests); impact their physical, mental, or social well-being; are interfering with some aspect of daily living (for example, school, work, home, or relationships); and persist for a minimum duration of 12 weeks after initial testing for COVID-19 (even if symptoms have waxed and waned over that period).
David Strain, MBChB, MD, chair of the BMA board of science and clinical senior lecturer and honorary consultant, University of Exeter (England), told the Science Media Centre: “A Delphi study builds a consensus from the world’s experts by presenting a series of statements and continuing to refine them until there is agreement as to what the definition of pediatric long COVID should be.” He added: “This is vitally important in order to align the global research effort into long COVID.”