Which statement about smoking cessation is the least accurate?

The statement indicating that smoking is not a risk factor for postoperative morbidity is the least accurate. Smoking is widely recognized to have negative effects on surgical outcomes, as it can impair healing, increase the risk of complications, and lead to longer recovery times following surgery.

Tobacco smoke affects the body's oxygen delivery and compromises the immune system, both of which are critical for recovery after surgical procedures. This has been extensively studied and recognized by healthcare professionals, so asserting that smoking does not influence postoperative morbidity contradicts established medical understanding.

In contrast, the other statements have more accurate foundations in medical literature. Carboxyhemoglobin levels, which measure carbon monoxide in the blood, do indeed return to normal relatively quickly after quitting smoking. Additionally, while chronic obstructive pulmonary disease (COPD) develops in a subset of smokers, it is noted that not all smokers will experience symptoms, with estimates around 15% being a reasonable figure. Finally, the recovery of mucociliary function is a well-documented process that can occur within a few weeks after cessation, which is in line with the timeline provided in the corresponding statement.