This story reminds me of my own pediatric medical - also at the age of 9!
My mother wanted me to undergo a real thorough medical at the local city hospital by a well known pediatric doctor.
So we got there at 2 pm and she "handed" my over to the reception desk to sign in. Afterwads she left the hospital and went back home - as I asked her for. After writing my name down I was told to go into the near waiting room until my name was called.
After about 10 minutes a nurse steped into the room and called my name. She took me over to the exam rooms. Once there, she told me to undress right down to my small white briefs. Being a small boy, she asked me if I needed some assistance, which of course I denied!
So I stepped out of all my clothes and only kept - as told by the nurse - my white briefs on.
After a while, she came back to the office and started to do my vitals (weight, heigt, blood pressure) and then the doctor entered into the room and introduced himself.
As I had to undergo a real thorough medical, he told me to remove my briefs as well and - once completly nude - to perform a so called "static test" which also included walking around on my toes. I also had to bend down and try to reach with my fingers on the floor. After that, all the other testing started (see the lines of "joe thom"). During aIl that time I had to remain completly naked until the Xray of my lungs, For this, I had to go into a special xray cabinet on the other side of the gangway. For this, I was allowed to put my briefs back on. Once the Xray was done, they led me into a seperate cabinet for the EKG testing, blood taking and also to give an urin sampel, which I had to do right in front of the nurse, while the doc completed his notes into my file.
Only after that I was allowed to dress again and could return back home. Alltogether a had to spend over 2 hours in that clinic.