Table 2

Summary statistics per eye and per patient for point-of-care image evaluation for identification of DR and referable DR

ATA category 1 evaluation (no or minimal DR vs. more than minimal DR)Referable DR*
Per eye
(n = 3,978)Per patient
(n = 1,989)Per eye
(n = 3,978)Per patient
(n = 1,989)
Total gradable images3,799 (95.5)1,944 (97.7)§3,758 (94.5)1,926 (96.4)
Sensitivity0.95 (0.94–0.97)0.96 (0.94–0.98)0.99 (0.97–0.99)0.99 (0.97–1.00)
Specificity0.84 (0.82–0.85)0.77 (0.75–0.80)0.76 (0.75–0.78)0.69 (0.66–0.71)
PPV0.66 (0.63–0.68)0.63 (0.60–0.66)0.43 (0.33–0.37)0.40 (0.37–0.44)
NPV0.98 (0.98–0.99)0.98 (0.97–0.99)1.00 (0.99–1.00)1.00 (0.99–1.00)
FDR0.34 (0.32–0.37)0.37 (0.34–0.40)0.57 (0.54–0.60)0.59 (0.55–0.63)
FOR0.02 (0.01–0.02)0.02 (0.01–0.03)0.002 (0.00–0.01)0.002 (0.00–0.01)
FPR0.16 (0.15–0.18)0.22 (0.20–0.24)0.24 (0.22–0.25)0.31 (0.29–0.33)
FNR0.05 (0.04–0.07)0.04 (0.03–0.06)0.01 (0.01–0.03)0.01 (0.00–0.03)
  • Data are n (%) or n (95% CI); FDR, false-discovery rate; FNR, false-negative rate; FOR, false-omission rate; FPR, false-positive rate; NPV, negative predictive value; PPV, positive predictive value.

  • *Referable DR is defined as moderate NPDR or worse, PDR, or presence of DME.

  • †When DR severity was evaluated per patient rather than per eye, the more severe level of DR and DME present in either eye was used as the severity present in the patient. If one eye was ungradable, the level of DR and DME present in the gradable eye was considered the level of DR and DME present in the patient.

  • ‡Images gradable at both the point-of-care evaluation by retina imagers and the reading center.

  • §In 41 eyes, the presence of DR was gradable, but the severity of DR could not be determined (e.g., definite signs of DR such as H/MA, but the disc and/or macula were obscured or the image quality in one or more quadrants did not allow for assessment of retinal lesions).

  • ∥In eight patients, the presence of DR was gradable, but the severity of DR could not be determined (e.g., definite signs of DR such as H/MA, but the disc and/or macula were obscured or image quality in one or more quadrants did not allow for assessment of retinal lesions).