title: Monitoring young people with type 1 diabetes for diabetic nephropathy: potential errors of annual ACR testing.
abstract: OBJECTIVE
  Type 1 diabetes guidelines recommend annual monitoring of albumin-creatinine ratio (ACR) to detect nephropathy. Annual monitoring for conditions such as dyslipidemia leads to high rates of false-positive diagnoses. We estimated rates of false-positive and false-negative diagnoses under annual, biennial and triennial monitoring.
  
  
  METHODS
  Using Oxford Regional Prospective Study (ORPS) data we modelled ACR over time. Using simulation we estimated numbers of positive and negative diagnoses and the proportion that are false, over 6 years of monitoring, when assessment intervals are 1, 2 or 3 years.
  
  
  RESULTS
  Average increase per year (95%C.I.) in ACR was 3,5% (2,0-5,0%) for males and 4,8% (3,2-6,5%) for females. By 6 years, annual monitoring would lead to 56 (49-63) false-positive diagnoses for every 100 positive diagnoses of micro-albuminuria, biennial to 49 (42-57) false-positives and triennial to 46 (39-53). For every 100 negative diagnoses, annual monitoring would lead to 1,2 (0,8-1,5) false-negatives, biennial to 2,3 (1,7-3,0) and triennial to 3,0 (2,2-3,8).
  
  
  CONCLUSIONS
  Less frequent monitoring would result in fewer false-positive diagnoses, but increased false negatives, or missed diagnoses. The clinical implications of these scenarios need further investigation through cost-benefit analysis.
authors: Department of Primary Health Care Sciences, University of Oxford and School of Primary Care Research, National Institute for Healthcare Research, United Kingdom. jason.oke@phc.ox.ac.uk
authors: Jason
authors: J
authors: Oke
authors: Andrew
authors: A
authors: Farmer
authors: Andrew
authors: A
authors: Neil
authors: R Neil
authors: RN
authors: Dalton
authors: David
authors: D
authors: Dunger
authors: Richard
authors: R
authors: Stevens
mesh_terms: D000419:Albuminuria / Q000175:diagnosis* / Q000652:urine; D002648:Child; D003404:Creatinine / Q000652:urine*; D003922:Diabetes Mellitus, Type 1 / Q000150:complications*; D003928:Diabetic Nephropathies / Q000175:diagnosis*; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008297:Male
chemical_list: D003404:Creatinine