We thank Chantelau for his thoughtful comments (1) on our study (2), and we recognize his pioneering work on the influence of patient compliance on the effectiveness of diabetic footwear. We characterized his 1990 and 1994 studies (3,4) as descriptive studies of footwear in the text and in Table 3 of our article on the basis of whether additional interventions were provided to patients. The 1994 study was characterized as a footwear study instead of a multifactorial study because the study had “no regular planning of visits” (4) as a study provision. If foot care had been scheduled at regular intervals in the intervention protocol, Chantelau and Haage’s study would have been classified as a multifactorial descriptive study.
We made our internal validity assessment of Busch and Chantelau’s 2003 study (5) and all other studies based on the information in the published literature in the English language. We did not contact any authors for additional information because all relevant information for the assessment of study validity should be available in the publications. Treatment allocation in Busch and Chantelau’s 2003 study was based on the determination of the insurance provider, an inappropriate strategy for ensuring randomization and balance in observed covariates across treatment arms. This approach to treatment allocation reduced internal validity and did not merit classification as a randomized trial. Finally, we agree that the footwear used in Busch and Chantelau’s 2003 study (5) reflects advances in therapeutic footwear design. We hope that this dialogue furthers reulceration prevention research and care for patients with a history of foot ulcers.
