What does individualized healthcare mean?

First generalization, then customization.

Scientific research is based upon comparisons between two or more groups. According to the purpose of the study, groups differ in terms of risk factors, test results, or treatments applied. It ensures that the groups are as similar as possible so that the outcome does not occur with a random probability. Thus, attention is paid to the fact that the only difference affecting the result is the variable, which is the study's primary aim.

Most individuals with other characteristics are excluded from these studies to form groups that are homogeneous and similar. The result is expressed as the significant statistical difference between the means of the groups.

On the contrary, other characteristics of the individual, if any, should be considered when applying an intervention that is effective in disease to an individual with that disease. Experts of the Guideline Committees, who examine the current clinical studies and other studies related to that disease, determine how an intervention found effective in a standard group can be applied to individuals in real daily practice as if by reverse engineering. In rare cases, the final decision goes to the individual's physician, as with other decisions.

In summary, science considers the average of groups in terms of objectivity, while experts and physicians focus on how to apply this "general" knowledge to a "special" case -- that is, to the individual.