Need more info.
How many people were tested. Age of the test group. LCD or tube monitor. Refresh rate used. Office or private use. Were there wanking on loli or MILF porn. Ventilated or unventilated room. Sizes of the monitors. Levels of radiation emitted by the monitors. Age of the monitors. City or countryside. Levels of pollution in the area. Coffee or tea.
'...the widespread use of computers is at unprecedented levels and it is reasonable to expect some effect on the visual system.' - what kind of scientific research is this.