This study compares the predictive validity of single-item and multiple-item measures of attitude toward the ad (AAd) and attitude toward the brand (ABrand), two widely measured constructs in marketing. The authors assess the ability of AAd to predict ABrand in copy tests of four print advertisements for diverse new products. They find no difference in predictive validity between single-item and multiple-item measures. The authors conclude that for constructs in marketing that consist of a concrete singular object and a concrete attribute, such as AAd or ABrand, single-item measures should be used. The study challenges the traditional preference for multiple-item measures in marketing research, which is based on the assumption that multiple items provide more reliable and valid data. However, the authors argue that for constructs like AAd and ABrand, which are concrete and singular, single-item measures are equally valid. They also find that multiple-item measures do not necessarily provide better predictive validity than single-item measures, as evidenced by the results of bivariate correlation and multivariate regression analyses. The authors also examine the potential for common methods bias, which occurs when constructs are measured in the same way, leading to inflated correlations. They find that this bias does not significantly affect the predictive validity of single-item or multiple-item measures in this study. Overall, the study concludes that single-item measures of AAd and ABrand are as valid as multiple-item measures and should be used when the constructs are concrete and singular. This finding has implications for marketing research and practice, as it suggests that single-item measures can be just as effective as multiple-item measures in certain contexts.This study compares the predictive validity of single-item and multiple-item measures of attitude toward the ad (AAd) and attitude toward the brand (ABrand), two widely measured constructs in marketing. The authors assess the ability of AAd to predict ABrand in copy tests of four print advertisements for diverse new products. They find no difference in predictive validity between single-item and multiple-item measures. The authors conclude that for constructs in marketing that consist of a concrete singular object and a concrete attribute, such as AAd or ABrand, single-item measures should be used. The study challenges the traditional preference for multiple-item measures in marketing research, which is based on the assumption that multiple items provide more reliable and valid data. However, the authors argue that for constructs like AAd and ABrand, which are concrete and singular, single-item measures are equally valid. They also find that multiple-item measures do not necessarily provide better predictive validity than single-item measures, as evidenced by the results of bivariate correlation and multivariate regression analyses. The authors also examine the potential for common methods bias, which occurs when constructs are measured in the same way, leading to inflated correlations. They find that this bias does not significantly affect the predictive validity of single-item or multiple-item measures in this study. Overall, the study concludes that single-item measures of AAd and ABrand are as valid as multiple-item measures and should be used when the constructs are concrete and singular. This finding has implications for marketing research and practice, as it suggests that single-item measures can be just as effective as multiple-item measures in certain contexts.