The evaluation of health or subjective health (SH) is considered a legitimate indicator of overall health status, providing a valid, reliable and cost-effective means of health assessment. This study looks at factors reported by respondents as influencing their SH, it analyzes to which extent people compare themselves with others when evaluating their health, and examines the difference between people with optimal or sub-optimal SH. Face-to-face interviews were conducted with 383 Israeli residents. Three models for judging health status were identified: the biomedical or disease oriented, the emotional or "general feeling", and the functional-related model. The reported influence of some factors for the evaluation of health changed by age and by level of subjective health. Respondents with sub-optimal health reported tiredness and pain as more influential. Most interviewees spontaneously reported comparing their health to reference groups. Age and level of subjective health were associated with the way people compare their health to others. The young reporting sub-optimal health did not compare themselves to people their age, but a high percentage of the old did so. Among those with excellent health, the young rather than the old were more likely to compare themselves to people their age. These findings imply that each individual tries to find ways to evaluate his/her health in a more positive light. When old and not healthy they tend to compare themselves to friends or people their age, but if young and not healthy they do not perform the comparison so as not to feel worse. Understanding how people evaluate their health can contribute to the conceptual development of subjective health.