Suchergebnisse

The purpose of the current research is to provide additional empirical findings directly related to monthly or seasonal variations in sample efficiency & response rates in telephone interviews. Second, we have expanded the analysis to include sample demographics within the data set to ascertain whether these items show variation across months. To test the hypothesis that there are monthly or seasonal variations in sample efficiency, we analyzed 2 years of Iowa Behavioral Risk Factor Surveillance Survey (Iowa BRFSS) data & 1 year of national data from the BRFSS. Time frames considered in the analyses were month, quarter, & season (summer/non-summer); variables examined included number of call attempts, contact rates, & cooperation rates. 4 Tables, 17 References. Adapted from the source document.