Inter-investigator variability and validity of stated hydrogel lens parameters

This study was designed to determine the variability and validity of various hydrogel contact lens parameters. The front vertex power of the contact lens was measured with the Nikon Projection Vertometer. The contact lens overall diameter, base curve, and center thickness were measured (for 59 hydrogel contact lenses) using the Hydro-Vue Soft Lens Analyzer, model 1100. These hydrogel lenses were measured by three investigators in a masked comparison. It was demonstrated that the inter-investigator variability was minimal for the measured lens parameters. However, the measured parameters differed significantly from those stated by the manufacturer.