[Telephone surveys for the study of catastrophic costs due to tuberculosis in Colombia: a novel toolPesquisas telefônicas para um estudo de custos catastróficos da tuberculose na Colômbia: uma ferramenta inovadora].

The study of catastrophic costs incurred by people affected by tuberculosis (TB), conducted in Colombia during the COVID-19 pandemic, provided the opportunity to implement telephone surveys for data collection. This constitutes a methodological innovation regarding the standards established by the World Health Organization (WHO) which, for this type of study, usually rely on face-to-face surveys of patients attending health facilities. The study design, objectives, and methodology were adapted from the WHO publication . A total of 1065 people affected by tuberculosis were selected as study participants and, by telephone, were administered a standard questionnaire adapted to the Colombian context. This allowed the collection of structured data on the direct and indirect costs faced by TB patients and their families. Greater than 80% completeness was achieved for all variables of interest, with an average survey duration of 40 minutes and a rejection rate of 8%. The described survey method to determine the baseline for further study of catastrophic costs in Colombia was novel because of its telephone-based format, which adheres to the information standards required to allow internationally comparable estimates. It is a useful means of generating standardized results in contexts in which the ability to conduct face-to-face surveys is limited.