The survey, as a research instrument, is vital for collecting and obtaining data in an orderly and effective manner. The objective of the study was to validate an instrument for collecting reliable and valid data on the knowledge, behavior and perception of patients with tuberculosis. The study was descriptive and cross-sectional with a design that included validation in two stages. First, consensus was reached among six experts regarding a 21-item questionnaire, which evaluated three dimensions: knowledge (12 items), behavior (3 items) and perception (6 items). Second, a pilot test was conducted with a sample of 30 patients to assess the categories of sufficiency, clarity, coherence and relevance. As to the values of sufficiency and relevance, 19 out of 21 items (90.5 %) matched, indicating a high level of adequacy and relevance, with an Aiken’s V value of 0.981429. At the clarity lev...