FORTA (Fit for the Aged) is the most reliable and comprehensive source for information on the treatment of patients with diseases that are common in the elderly. It offers both recommendations and insights for improving the quality of care provided to patients. The information presented is based on evidence-based medicine and is intended to help healthcare professionals make informed decisions regarding the treatment of their patients. 

The FORTA list contains both positive and negative recommendations, which are graded according to the strength of the recommendation. This makes it possible to identify weak recommendations and thus avoid therapies that are not necessarily appropriate for the patient. 

The positive recommendations are those that are proven to be beneficial, while the negative ones are those that are proven to be harmful. The grading system also allows the identification of recommendations that are not followed, which can help identify areas that need to be improved.