April 2011
Volume 52, Issue 14
ARVO Annual Meeting Abstract  |   April 2011
Validation of a Composite Scoring System for the Prediction of Advanced Age-related Macular Degeneration
Author Affiliations & Notes
  • Chung-Jung Chiu
    Human Nutrition Res Ctr, Tufts University, Boston, Massachusetts
  • Paul Mitchell
    Centre for Vision Research,, University of Sydney, Westmead Hospital,, Sydney, Australia
  • Allen Taylor
    Human Nutrition Res Ctr, Tufts University, Boston, Massachusetts
  • Footnotes
    Commercial Relationships  Chung-Jung Chiu, None; Paul Mitchell, None; Allen Taylor, None
  • Footnotes
    Support  USDA under agreements 1950-5100-060-01A, Ross Aging Initiative
Investigative Ophthalmology & Visual Science April 2011, Vol.52, 90. doi:
  • Views
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Chung-Jung Chiu, Paul Mitchell, Allen Taylor; Validation of a Composite Scoring System for the Prediction of Advanced Age-related Macular Degeneration. Invest. Ophthalmol. Vis. Sci. 2011;52(14):90.

      Download citation file:

      © ARVO (1962-2015); The Authors (2016-present)

  • Supplements

Using 5 demographic and 3 ophthalmic predictors in a logistic regression to model result-specific likelihood ratios in the American Age-Related Eye Disease Study (AREDS) dataset (8-y follow-up), we devised a composite (C) scoring system (CAREDS scoring system: CAREDS = -4.48 + ΣCj, AREDS) that permits the prediction of advanced age-related macular degeneration (AMD) (AREDS model in Table 2). The objective of this study is to validate this AREDS model in the Australian Blue Mountains Eye Study (BMES) cohort (10-y follow-up).


To evaluate the performance of the CAREDS scoring system, we first assigned CAREDS score to all eligible eyes in the BMES cohort (Fig 1). Then, at various C score cutoff points each eye was classified into "positive" or "negative" according to its CAREDS score. Next, through frequency table analysis of this classification vs. the actual status of progression to advanced AMD, we calculated the empirical sensitivities/specificities and measured the area under the receiver operating characteristic (ROC) curve (c-indexBMES/AREDS). To explore the deviation of the BMES dataset from the AREDS model, we developed a prediction model (CBMES scoring system) using the BMES dataset as the training sample and compared it to the CAREDS scoring system (Table 2).


The c-indexBMES/AREDS (= 0.921) implies an excellent performance of the CAREDS scoring system in the BMES cohort. However, the empirical sensitivities/specificities deviate from the expected values (Table 1). Although both CAREDS (c-indexAREDS = 0.877) and CBMES (CBMES = -16.26 + ΣCj, BMES, c-indexBMES = 0.953; Fig 2) scoring systems have excellent internal validity, further analysis implies that the deviation is due to the differences in baseline risk factor profile and duration of follow-up between the two cohorts.


These results suggest that, while the methodology of the C scoring system is valid, it will be optimal to use long-term follow-up data from multiple cohorts in order to develop a widely applicable model for the prediction of advanced AMD.  

Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: risk factor assessment • clinical research methodology 

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.