A public education campaign was developed with the aim of lowering the incidence of skin cancer in the population - HSC - SSCE Biology - Question 9 - 2020 - Paper 1

To measure the effectiveness of the campaign, the most valid method is to compare skin cancer incidence rates before and after the campaign was implemented. This option provides a clear comparison of the outcomes attributable to the campaign, establishing a direct correlation between the intervention and changes in skin cancer rates. It allows researchers to assess whether the campaign led to a statistically significant decrease in incidence, thereby demonstrating its effectiveness.