The study involved examining the skin on the backs of the hands of the participants at the initial stage of the study, and again about four and a half years later. The examinations showed microscopic changes in the skin over this period of time, which are related to signs of aging skin. Trained assessors also graded the lines and skin texture (coarseness) of the hands on a six-point scale. When all was said and done, the results showed a significant difference in the amount of skin damage between the two groups. The researchers were able to quantify these results, and have concluded that those who applied the sunscreen on a regular basis showed almost 25% less skin aging than those who applied it at their discretion. They point out that in addition to reducing the skin damage, the regular application of sunscreen has the added benefit of lowering the risk of skin cancer.