Pre-screening measures derived from a cognitive-behavioral theory of health anxiety were significant predictors of individual differences in post-screening reactions to a health screening procedure, bone densitometry. Predictors included specific illness beliefs (vulnerability, severity/consequences, coping and treatment) and general health anxiety measures. Three months after a low bone mineral density (BMD) result, women with high levels of pre-existing general health anxiety gave higher ratings of anxiety about osteoporosis and perceived likelihood of developing osteoporosis than women with low levels of preexisting health anxiety, even though the two groups' initial ratings had not differed significantly. Women with a low BMD result generally showed "minimization" of the seriousness of low BMD but women with very high levels of pre-existing health anxiety did not. After a high BMD result, highly health anxious women were only temporarily reassured. The results were consistent with the cognitive-behavioral analysis of health anxiety.