Table 6

 Incidence and relative risk of non-severe and severe keratitis with various threshold clinical severity scores

Wearing modalityLens typeThreshold score* = 4Threshold score = 6Threshold score = 8Threshold score = 10Threshold score = 12
Non-severe keratitisSevere keratitisNon-severe keratitisSevere keratitisNon-severe keratitisSevere keratitisNon-severe keratitisSevere keratitisNon-severe keratitisSevere keratitis
AI†RR‡AIRRAIRRAIRRAIRRAIRRAIRRAIRRAIRRAIRR
*A score equal to or less than the threshold score is classified as non-severe keratitis.
†Annual incidence, expressed as the number of cases per 10 000 wearers per year.
‡Relative risk, calculated independently for non-severe and severe keratitis, taking “daily wear hydrogel” as the referent in each case.
§Indeterminable because of an annual incidence of zero.
Daily wearRigid1.41.17.10.42.90.35.70.55.70.42.90.47.10.41.40.58.60.40.0§
Hydrogel daily disposable2.41.811.60.63.70.410.40.99.10.74.90.810.40.63.71.213.40.70.60.6
Hydrogel1.31.019.11.09.41.011.01.014.11.06.41.017.41.03.01.019.41.01.01.0
Silicone hydrogel0.0§55.92.955.96.00.0§55.94.00.0§55.93.20.0§55.92.90.0§
Extended wearRigid0.0§0.0§0.0§0.0§0.0§0.0§0.0§0.0§0.0§0.0§
Hydrogel0.0§144.67.624.12.6120.510.948.23.496.415.296.45.548.216.0120.56.224.124.0
Silicone hydrogel13.29.8105.45.565.97.052.74.898.87.019.83.1105.46.113.24.4112.05.86.66.6