VHI, Laya, Irish Life (and HSF Cash Plans) are all forms of private medical health insurance and if you are part of a company health scheme you may see these premiums appear on your payslip.
If a value appears in your payments section (preceded by "NP") the premium is paid by your employer as part of your employment contract. These premiums are considered as benefits, and are therefore subject to taxes, i.e., the figure is not a value you receive but rather a value shown for the purposes of your overall tax calculation. The NP on the Jefferson payslip stands for Notional Pay.
If a value appears under your deductions section, it is a net value (i.e., after tax) deducted directly from you to pay for your health insurance premium.
Some payrolls have an entry under both your payment and deduction sections if your employment contract only covers the benefit for you (and not for any members you add to your policy, e.g., your spouse or children). The value of the premiums for these additional members are then deducted as a net value.
For more on health insurance please visit www.hia.ie