highly significantP <0.0001
Results There was a highly significant Kendall rank order correlation between cataract scores for the two eyes (Kendall τ = 0.48, P <0.0001), this score was significantly repeatable ( R = 0.72 (SE = 0.02), F = 6.09, d.f. = 1077, 1144, r 2 = 0.85, P <0.0001), and, we used the mean score in subsequent analyses.