The objective of this study was to assess adaptation and feasibility of practice guidelines for thyroid nodule management. For one month physicians completed a self-administered semi-structured questionnaire concerning a draft version of the guidelines for each consecutive patient. A sample group of 20 endocrinologists, 20 surgeons and 120 general practitioners from all parts of France took part in this study. The main outcome measures were whether the case description was found by the physicians, and whether recommendations were found and agreement with these recommendations were assessed. We found that two hundred and fifty-three patients (of whom 85% were women) were included in the study: 52% were seen for a surgical decision; 20% for diagnosis or screening and 28% for follow-up. Four percent of the women were pregnant; 2% of the patients had a large nodule; and 2%, a retrosternal nodule. These last three situations had not been well identified in the draft guidelines. The patient's case description was appropriately identified in 75% of the responses. Most cases reported as being not found were, however, covered by the guidelines. Physicians in private practice were less likely than the others to identify their patient's cases. Physicians agreed with the recommendation in 77% of cases. General practitioners were more likely and endocrinologists less likely than surgeons to disagree. Most disagreements and alternative proposals were not evidence-based. Our conclusion is that this study shows that the draft guidelines were applicable, and allowed minor improvements of the final version. Adapting guidelines to practice could improve their use and, consequently, the quality of health care.