My doctor refers books before making a decision, I think he lack knowledge or confidence?

If Your doctor is referring books then he is justifying his duties!

Doctors are highly skilled and trained individuals who have invested a considerable amount of time and resources in their education and training. While their knowledge and expertise are highly valuable, it's important to acknowledge that no one can remember all information all the time. With the advent of evidence-based medicine and technological advancements, it has become the norm for doctors to consult medical literature and resources when making treatment decisions and prescribing medication.

Medical professionals have access to a vast array of resources, including medical textbooks, journals, clinical practice guidelines, and online databases, which can aid them in their decision-making process. These resources can help doctors stay up-to-date with the latest research and evidence-based practices, allowing them to provide the best possible care to their patients.

In addition to consulting these resources, doctors are trained to critically evaluate the information they read and to weigh the benefits and risks of different treatment options before making a recommendation to their patients. As a result, it is not uncommon for doctors to consult multiple sources before making treatment decisions.

Ultimately, the goal of consulting medical literature and resources is to provide patients with the most effective and safe treatment options available. By staying up-to-date with the latest research and evidence-based practices, doctors can provide their patients with the highest quality care possible.