The use of statistical methodology to determine the accuracy of grading within a diabetic retinopathy screening programme

Oke, J L, Stratton, I M, Aldington, S J, Stevens, R J and Scanlon, Peter H ORCID: 0000-0001-8513-710X (2016) The use of statistical methodology to determine the accuracy of grading within a diabetic retinopathy screening programme. Diabetic Medicine, 33 (7). pp. 896-903. doi:10.1111/dme.13053

Text (Wiley Online Open Article)
The use of statistical methodology.pdf - Published Version
Available under License Creative Commons Attribution Non-commercial 4.0.

Download (132kB) | Preview


AIMS: We aimed to use longitudinal data from an established screening programme with good quality assurance and quality control procedures and a stable well-trained workforce to determine the accuracy of grading in diabetic retinopathy screening. METHODS: We used a continuous time-hidden Markov model with five states to estimate the probability of true progression or regression of retinopathy and the conditional probability of an observed grade given the true grade (misclassification). The true stage of retinopathy was modelled as a function of the duration of diabetes and HbA1c . RESULTS: The modelling dataset consisted of 65 839 grades from 14 187 people. The median number [interquartile range (IQR)] of examinations was 5 (3, 6) and the median (IQR) interval between examinations was 1.04 (0.99, 1.17) years. In total, 14 227 grades (21.6%) were estimated as being misclassified, 10 592 (16.1%) represented over-grading and 3635 (5.5%) represented under-grading. There were 1935 (2.9%) misclassified referrals, 1305 were false-positive results (2.2%) and 630 were false-negative results (11.0%). Misclassification of background diabetic retinopathy as no detectable retinopathy was common (3.4% of all grades) but rarely preceded referable maculopathy or retinopathy. CONCLUSION: Misclassification between lower grades of retinopathy is not uncommon but is unlikely to lead to significant delays in referring people for sight-threatening retinopathy.

Item Type: Article
Article Type: Article
Related URLs:
Subjects: R Medicine > RA Public aspects of medicine > RA645.A-Z Individual diseases or groups of diseases, A-Z > RA645.D54 Diabetes
R Medicine > RE Ophthalmology
Divisions: Schools and Research Institutes > School of Education and Science
Research Priority Areas: Health, Life Sciences, Sport and Wellbeing
Depositing User: Anne Pengelly
Date Deposited: 16 Mar 2016 10:00
Last Modified: 31 Aug 2023 09:09

University Staff: Request a correction | Repository Editors: Update this record

University Of Gloucestershire

Bookmark and Share

Find Us On Social Media:

Social Media Icons Facebook Twitter Google+ YouTube Pinterest Linkedin

Other University Web Sites

University of Gloucestershire, The Park, Cheltenham, Gloucestershire, GL50 2RH. Telephone +44 (0)844 8010001.