G I G O 
This post is for CH who, as a medical professional, will be interested but not surprised by its contents
In the early days of business computing this was a popular acronym -
Garbage In - Garbage Out
This is a snappy way of conveying:
The integrity of computer data output is dependant and significantly  reliant on the quality, accuracy and relevance of the data entered.
When we arrived in Aylesbury I registered with a local doctors' practice.  On my first consultation with the GP I encountered a touch-screen check-in interface module. By confirming my date of birth and sex (or *Gender as they insist on calling it) all human interaction with the receptionist, to whom I had been required to divulge my medical concerns before being granted an appointment, was eliminated.  This device, however, rejected me because I had naively entered my correct date of birth unaware at this time that the international date line passes through Aylesbury and that I was in fact one day older than I thought. When I pointed this out my records were adjusted to make me exactly one year younger than my parents had led me to believe.
It was a few weeks before I appreciated that this had been achieved by setting up a second record for me and recording appointments, diagnoses and prescriptions randomly against these two records. I was a little suspicious when the GP refused to believe that I had visited her six months before despite my having the results of a blood test she had requested and two boxes of pills she had prescribed. In my ignorance I presented a prescription at the pharmacy claiming exemption from charges on the grounds of my age.  The pharmacist, however, could read numbers as well as words and refused to dispense the medication as the prescription showed my age as 27 years younger than qualifying age. Like many incredibly handsome men I can be vain sometimes but even I would not have tried that one.
Before the days of computers when information was recorded by hand and figures added up in the head with cross-checks to maintain accuracy I learned that if the difference between two figures which should be the same was divisible by nine, then the error was likely to be one of transposition.  Hence the error on my prescription was clearly evident to me.
I advised the practice manager of my diagnosis and the remedy was put into the hands of a specialist.   The result was that I now had a single medical record with the correct date of birth.  Surgical procedures often  have unexpected, or unexplained, consequences for the patient. So it was for me: the unwanted record was removed but along with it went all my medical information, historical and current.
I am sure there is an appropriate medical term for this condition but as a layman I can only think of decidedly non-medical expressions.
I have been told that all is now well as the missing information has been recovered from archives, waste paper bins etc and re-input into my record.
Why am I not re-assured by this prognosis?

*NOTE FOR FOREIGN READERS

The application of the word Gender to people and animals is questionable in my view. People and animals can be divided into male and female sex.  There are three genders - masculine, feminine and neuter. it can be appreciated that the word sex and gender are not interchangeable.