2020-12-02, 11:10–11:25, Zoom Breakout Room 1
Dual frame surveys using mobile and landline telephone numbers have been the predominant method of sampling for CATI interview studies in Australia for several years now, however neither frame is without its problems. Landline telephones can only be used to access 49% of the population, with coverage heavily skewed towards older age groups. Mobile telephones are not inherently linked to a geographic location meaning that obtaining geographically targeted samples is expensive, often prohibitively so. Commercial sample providers have recently improved their offering for “listed” mobile phone numbers with geographical information attached, however these lists also have coverage errors particularly for younger age groups. This presentation reports on work carried out for a large state-level survey to determine an optimum blend of sample sources including listed and RDD mobile phones alongside landline sample. The survey is state-wide, but includes a sample quotas for each of the 79 LGAs in the state, so requires a large degree of geographical targeting. Several simulations were carried out using a variety of different sample mixes to determine the most cost-effective solution.