To clarify, I didn’t say that I’d use chest wall tenderness as a reliable method to “exclude” PE. A high proportion of primary care patients, if you palpate their chest wall vigorously enough, will report tenderness, so I’m not generally reassured by this physical finding alone, especially in the absence of any history of chest wall trauma and when a potentially more serious diagnosis is on the differential.
However, I do agree that many primary care presentations are undiagnosable and that many of these will end up being self-limited. Family physicians’ and ER physicians’ roles are primarily to “catch the bad stuff.” Over time, primary care physicians have to become very comfortable with managing uncertainty. The key is providing proper instruction as to when the patient should seek followup (e.g., if symptoms are getting worse rather than better/if new symptoms develop/if symptoms don’t resolve within a certain timeframe). I’m sure my patients wouldn’t feel reassured by hearing this, but sometimes I look back, at the end of a clinic day, and realize that I don’t know what any of them had ! 