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Question: Hi, Thank you for your previous comprehensive reply. Households per census tract in our town range between 1,062 and 3,307. For these upper and lower limits, how many households need to respond for a statistically valid sample. Thank you!
Answer: This is a great question, but I'm afraid that there are not easy answers for you. The best answer I can provide is: "It depends!" There are several issues related to sample size that must be taken into consideration. One is the size of the interview/questionaire, another is response rate, another is what level of change you wish to detect, another is to what extent do you want to generalize the findings to a broader population, and another is how you will use the data. You will need to contact a local epidemiologist or biostatistician for the best help. Some may charge for this service, but many universities have consulting groups that can be very cost effective in this area. We wish you the best in your efforts.
Question Date: Fri, 04/20/2007