Anna Brouwer

Lower lid position Fornix position P-value A-wave* 0.3 24.2 21.8 0.054 1.0 19.6 19.3 0.904 3.0 17.7 15.7 0.014 10.0 15.5 14.5 0.202 B-wave* 0.3 21.2 19.7 0.187 1.0 20.5 19.3 0.267 3.0 36.0 33.7 0.239 10.0 32.7 30.8 0.259 30 Hz flicker* 21,8 20.5 0.256 Table 4: Coefficient of Variation of amplitudes of the two DTL positions CoV of amplitudes were calculated after data were transformed to fit a normal distribution of two DTL positions (lower lid position and fornix position). The R package cvequality (Version 0.1.3; Marwick and Krishnamoorthy 2018) was used to test for significant differences in CoV of the two DTL positions. Based on Bonferoni’s correction (more tests than shown in this table), p-values below < 0.006 were considered as statistically significant. *Results of different flash strengths in candela . seconds/meters squared of the light adapted ERG Abbreviations: ERG = electroretinogram, DTL = Dawson, Trick, Litzkov electrode, CI = confidence interval, CoV = coefficient of variation. ICC CI A-wave amplitude* 0.3* 0.584 0.494 0.658 1.0 0.654 0.578 0.715 3.0 0.678 0.608 0.736 10.0 0.716 0.655 0.767 A-wave implicit time* 0.3 0.788 0.742 0.826 1.0 0.830 0.793 0.860 3.0 0.856 0.825 0.882 10.0 0.857 0.826 0.883 B-wave amplitude* 0.3 0.865 0.836 0.889 1.0 0.900 0.878 0.918 3.0 0.885 0.860 0.905 10.0 0.842 0.807 0.870 B-wave implicit time* 0.3 0.946 0.934 0.955 1.0 0.973 0.967 0.978 3.0 0.954 0.944 0.962 10.0 0.982 0.978 0.985 30 Hz flicker Peak amplitude 0.897 0.874 0.915 implicit time 0.979 0.975 0.983 ICCs showing reliability between the ERG with two DTL positions: lower lid position and fornix position. *Results of different flash strengths in candela . seconds/meters squared of the light adapted ERG Abbreviations: ICC = Intraclass correlation coefficient, ERG = electroretinogram, DTL = Dawson, Trick, Litzkov electrode, CI = confidence interval. Table 3: Intraclass correlation coefficient between the two DTL positions 30 Hz flicker response. As is to be expected, the biggest variance between the two DTL positions is seen at lower stimulus strengths, because the signal is relatively low compared to the noise. The implicit time difference is evenly spread around zero in all measuring conditions. However, the amplitude ratio was in approximately 75% higher than 1.0. This implies that in approximately 75% of eyes the amplitude was higher in the LLP compared to the FP. 147 General introduction, aims and scope 7