Factors influencing participation rates in clinical late effect studies
of childhood cancer survivors
Abstract
Introduction: Several studies on late effects of childhood cancer have
been conducted during the past decades. To ensure external validation of
a study population, the participation rate must be high. This study
investigated demographic data in late effect studies and potential
factors impacting on participation rates such as cancer type, time since
diagnosis and duration of clinical examinations. Procedure: By searching
the databases PubMed, Embase and Web of Science and by contacting
researchers and clinicians, we identified studies including an
invitation to a clinical examination for late effects after childhood
cancer. Studies conducted from January 2010 - March 2020 in the Nordic
countries were included. Results: We found 80 published studies
originating from 16 cohorts. The overall participation rates ranged
between 27 and 100%. The majority of studies (eleven studies) were
conducted more than ten years after the cancer diagnosis and primarily
on hematologic malignancies (seven studies). The highest participation
rates were seen in studies of survivors with solid tumors (92%) and the
lowest in survivors with hematologic malignancies (67%) and central
nervous system tumors (73%). Neither duration of the clinical
examination nor time since diagnosis seemed to affect the participation
rate. Conclusion: A trend of lower participation rates when recruiting
survivors of hematologic malignancies and central nervous system tumors
was found. We encourage future studies to describe the recruitment
process more thouroughly to improve understanding of the factors
influencing participation rates.