Table 2

Non-parametric Kruskal-Wallis tests and post hoc pairwise comparisons for parafoveal capillary density and per cent area deviated from normal distribution measurements in three study groups

Region of interestMean±SD%Kruskal-Wallis testsPost-hoc pairwise comparisons
ControlNP-SCRP-SCRControl vs NP-SCRControl vs P-SCRNP-SCR vs P-SCR
Parafoveal capillary density
Entire image41.45±1.9537.19±4.0036.43±3.46P<0.001*P<0.001*P<0.001*P=0.980
Temporal41.53±2.0336.28±5.5834.92±5.86P<0.001*P<0.001*P<0.001*P=1.000
Nasal41.79±2.1337.81±3.6537.65±2.84P<0.001*P<0.001*P<0.001*P=1.000
Superior41.38±2.1836.98±4.4335.95±3.93P<0.001*P<0.001*P<0.001*P=1.000
Inferior41.15±2.1637.46±4.3236.97±3.22P<0.001*P<0.001*P<0.001*P=1.000
Per cent yellow area
Entire image4.59±3.7515.94±14.9018.00±11.72P<0.001*P<0.001*P<0.001*P=0.833
Temporal4.31±4.5819.94±22.7124.07±20.18P<0.001*P<0.001*P<0.001*P=0.689
Nasal3.75±2.9613.49±12.4013.44±10.60P<0.001*P<0.001*P<0.001*P=1.000
Superior4.71±4.6116.56±16.0820.76±14.37P<0.001*P<0.001*P<0.001*P=0.614
Inferior5.59±4.3114.99±16.1315.12±11.74P=0.008*P=0.023*P=0.017*P=1.000
Per cent red area
Entire image0.76±0.925.96±9.656.92±6.62P<0.001*P=0.001*P<0.001*P=0.346
Temporal0.60±0.919.41±17.3912.65±15.51P<0.001*P=0.002*P<0.001*P=0.568
Nasal0.51±0.954.05±5.973.91±4.75P<0.001*P<0.001*P<0.001*P=1.000
Superior0.86±1.256.15±10.698.43±9.85P<0.001*P=0.004*P<0.001*P=0.178
Inferior0.99±1.275.47±12.444.44±5.38P=0.011*P=0.035*P=0.017*P=1.000
  • *P<0.05.

  • NP-SCR, non-proliferative sickle cell retinopathy; P-SCR, proliferative sickle cell retinopathy.