The use of self-assessed health status (SAHS) as a measure of health is common in empirical research. We analyse a unique Australian survey in which a random sub-sample of respondents answer a standard self-assessed health question twice-before and after an additional set of health related questions. A total of 28% of respondents change their reported health status. Response reliability is related to age, income and occupation. We also compare the responses of these individuals to other respondents who are queried only once, to isolate effects of question order and mode of administration.