Introduction:

The diabetic foot is a complication of diabetes mellitus and every 20 seconds an amputation by this cause is performed. The adequate stratification of the patient with diabetic foot allows timely actions to avoid, in a high percentage of cases, amputations.

Objective:

To validate a predictive model for amputation risk in patients with diabetic foot.

Methods:

Prospective longitudinal study. The sample consisted of 280 patients divided into two groups. The variables used to prepare the model were: age, hematocrit, leukocytes, lymphocytes, neutrophils, albumin, neutrophil/lymphocyte index, platelets, creatinine, lesion size and lesion grade. A predictive model was applied whose score allowed each patient to be individually stratified.

Results:

An internal validation was performed with 60 % of the sample, which showed good discriminatory capacity for 96.0 % with a sensitivity of 57.69 %, a positive predictive value of 95.4 % and a Cronbach's Alpha of 0.71. In the final test and debugging of the model, 40% of the sample was worked with and external validation was carried out using Cronbach's Alpha statistic = 0.85. The test group had a specificity of 97.40% and a positive predictive value of 96.65, which was higher than the training group.

Conclusions:

The predictive model proved to be a useful tool for the stratification of patients with diabetic foot and allowed to apply an appropriate behavior in each patient.