More than 652,000 sick notes were issued in Abu Dhabi emirate last year, almost 12 times more than the number recorded the year before, after a stringent electronic system was introduced for approval of leave.
The total is made up of short and long-term illnesses, and includes notes submitted to public and private healthcare centres. The vast majority, 538,000, were short-term.
Emirati sick-leave requests made up 68 per cent - 442,943 of 652,632.
This is the first time the Health Authority Abu Dhabi, or Haad, has provided thorough figures on short and long-term sick notes after introducing the sick-leave approval system in March last year.
Almost 14 per cent of the total notes issued last year - 89,546 - were not considered legitimate and were rejected or sent back to the issuing physician for further detail.
To lessen abuse of the system sick notes must be as detailed as possible, said Dr Jamal Al Mutawa, the manager of the external services department at Haad.
"Usually, without any clarification or if the period of leave is not as we recommend, then we return to the doctor and say either provide more information for the long period or we are not going to accept it and will reduce it."
Men had sick leave more often than women, with 390,000 notes.
The most common reasons for short-term leave were acute pharyngitis (sore throat), bronchitis and fever, while the most common for long-term leave were for hernia repair (4.28 per cent) appendectomies (3.39 per cent) and meniscus knee disorders (2.95 per cent).
Haad regulations state short-term leave can last up to one week, and long-term leave is applied to any period of more than seven days.
Several hospitals are still to implement the system, meaning the total number of sick notes from Abu Dhabi, Al Ain and the Western Region is still unavailable, said Dr Al Mutawa.
Reminders have been sent telling all health centres to comply, he said.
Every Sunday a medical committee at Haad, comprising experts from different fields, meets to review sick notes.
With the electronic system, doctors can easily check for suspicious behaviour, said Rashed Al Shaeel, Mafraq Hospital's chief of orthopaedic surgery.
"If a patient goes to Al Ain and then the next day he comes to me, I can see," Dr Al Shaeel said. "Medication-wise, sick leave-wise, everything is there."
Last year, two healthcare workers were found to be abusing the system. Breaches are referred to the health system compliance division.
One doctor at Sheikh Khalifa Medical City was jailed last year and fined Dh50,000 after being convicted of issuing fake sick notes, for which he charged Dh500 each.
While the system works there are some weaknesses that need to be ironed out, said Dr Maurice Kallas, a general surgeon and head of emergency and GP departments at the Khalifa Street branch of Al Noor Hospital.
"There are positive and negative points," Dr Kallas said. "The positives are that it will reduce abuse of the system of the sick leave, but on the other side it will take a long time for the doctor to issue sick leave, between 15 and 20 minutes."
Doctors are also limited by their specialities, said Dr Kallas, who issues about 30 sick-leave notes a month. Surgeons, for example, are not able to issue a sick note for someone with flu. But the system does provide information on the number of days off that can be given depending on the condition.
This is because some doctors had been giving patients too much leave, said Dr Al Mutawa.
Haad is working on improving the system, said Dr Kallas.
"We are sending them some notes about weak points of the system and they are trying to update and improve," he said. "The system really reduces the sick leave numbers. Before, there was much abuse."
Haad also expects to add sick leave forms to its system for carers - people such as parents who must take time off work to look after sick children.