title: Sensitivity and specificity of a new test for thermographic evaluation of the foot in the diagnosis of diabetic peripheral polyneuropathy.
abstract: OBJECTIVE
  This work determined the sensitivity, specificity, and predictive values of a test evaluating the thermal perception threshold to cold and heat and established a thermal interval with the participant's basal temperature in order to detect diabetic peripheral neuropathy in 172 people with diabetes, 86 with and 86 without diabetic neuropathy.
  
  
  METHODS
  This was a cross-sectional, diagnosis accuracy study.
  
  
  METHODS
  This research was performed from January 2010 to February 2012 in Seville, Spain, and Córdoba, Spain.
  
  
  METHODS
  One hundred seventy-two people with diabetes, 86 with and 86 without diabetic neuropathy, were recruited to participate in the study.
  
  
  METHODS
  The thermal sensitivity was examined in the participants' feet with an instrument designed to assess thermal discrimination and sensitivity based on the Peltier principle. The skin temperature was recorded, and it was performed the following tests: (1) determining the thermal discrimination threshold, used to identify the lowest noticeable temperature difference, and (2) examining the thermal sensitivity, used to determine the absolute thermal threshold. The receiver operating characteristic curve technique was used to calculate the sensitivity, specificity, and predictive values.
  
  
  RESULTS
  The area under the curve that showed the best sensitivities and specificities bilaterally was for the warm temperatures under the first and fifth metatarsal heads. In these zones, the temperature difference needed to predict whether a patient was neuropathic was 2°C. Sensitivities were greater than 75%, and the positive predictive values in all cases exceeded 60%.
  
  
  CONCLUSIONS
  This technique enabled the authors to quantify the degrees of colder or warmer temperature differences that participants with diabetes (with and without neuropathy) needed to be able to detect a difference, with acceptable sensitivity, specificity, and predictive values.
authors.affiliation: Raquel García-De-La-Peña, PhD, is an honorary assistant at the Department of Podiatry at the University of Seville, Seville, Spain. Salomón Benhamú, PhD, is a lecturer at the Department of Podiatry at the University of Seville, Seville, Spain. Pedro V. Munuera, PhD, is a lecturer and department director at the Department of Podiatry at the University of Seville, Seville, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: García-De-La-Peña
authors.forename: Salomón
authors.initials: S
authors.lastname: Benhamú
authors.forename: Pedro V
authors.initials: PV
authors.lastname: Munuera
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D003929:Diabetic Neuropathies / Q000175:diagnosis*; D005260:Female; D005528:Foot / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012684:Sensory Thresholds; D012881:Skin Temperature; D013817:Thermography / Q000379:methods*; D013697:Thermosensing