In contrast to the media monitoring data which include both the paid and pro bono components and cover the period from baseline through 5 months of the intervention, the media buying information focuses only on the paid component -- which Phase I sought to evaluate and covered January through June 1998. Thus, the planned media buy and post-buy information are critical for assessing audience exposure to ads and their correlation to changes in awareness. The initial goal for the media buying plan was to reach 90 percent of each of the target audiences (i.e., youth, teens, parents, and other adult influencers) with four exposures a week through the paid component of the campaign. For Phase 1, the Nielsen measured target definition of teens aged 12 to 17 and adults aged 25 to 54 were used for all local market broadcast media planning and buying purposes. As a result, the reach and frequency objectives were adjusted to reach 93 percent of youth and teens combined an average of 7.6 times per week and 92 percent of adults (aged 25 -- 54) 5.9 times per week inclusive of all media types (i.e., television, radio, newspaper, and outdoor). It is important to note that GRP data for youth ads rely on teen GRPs as a proxy. Although youth are defined as 4th through 6th graders (ages 9 -- 11), GRPs calculated for youth ads are based on Nielson’s definition of the teen audience (ages 12 -- 17).

As final post-audited data on the reach and frequency for Phase I was unavailable by medium as this report was being prepared, GRP data are used as proxy measures and are based on post-buy and planned media schedules. (Estimated variance between the buy information provided and the audited post-buy information is plus or minus 10 percent.)

A gross rating point is a unit of measurement of advertising audience size equal to one percent of the total potential audience universe. It is used to measure the exposure of one or more programs or commercials without regard to multiple exposure of the same advertising to individuals. A GRP is the product of media reach times exposure frequency.

As an example, if an ad were aired on a program that 40 percent of the population was exposed to, the rating for the program would be 40. The ad might also be aired on other programs yielding a total of 200 gross rating points. For the total number of programs, 80 percent of the population may ultimately be exposed to the ad at least one time. This would translate into a reach of 80 percent. The average frequency is derived by dividing the gross rating points (200) by the reach (80), resulting in an average frequency of 2.5 times. Reach, frequency, and GRPs are interrelated.

The media buying plan information was used to identify the specific ads comprising the intervention in each site and the total advertising weight delivered in each site and for the individual ads. The media buying contractor provided available data on analyses of "as purchased" or planned television activities for the youth/teen and adult television buys. This information includes the frequency, or number of times, each spot or ad aired in a site and the estimated gross rating points (GRPs) for each ad as well as average GRPs for each ad.