New York: An average of three in ten employees call in sick to their office when not actually ill, with some giving unusual excuses like their dog having a nervous breakdown to they themselves suffering from a broken heart, a new survey says.

As per the survey conducted by U.S-based human capital services provider Careerbuilder, 30 per cent of workers have called in sick when not actually ill in the past year.

The sick days, legitimate or otherwise, also become more frequent around the winter holidays, with nearly one-third of employers reporting more employees call in sick during the holiday season, the survey found.

At the same time, 29 per cent of employers have checked up on an employee to verify that the illness is legitimate, usually by requiring a doctor's note or calling the employee later in the day.

Some employers have had other employees call a suspected faker (18 per cent) or even gone so far as to drive by the employee's home (14 per cent).

Besides, 17 per cent of employers have fired employees for giving a fake excuse, Careerbuilder said.

The most unusual excuses given by the employees calling in sick included the employee's sobriety tool not allowing the car to start, the worker forgetting he had a job, his or her dog having a nervous breakdown and the employee's dead grandmother being exhumed for a police investigation.

Employees also gave excuses like their toe getting stuck in a faucet, getting bitten by a bird, being upset after watching 'The Hunger Games', getting sick from reading too much, suffering from a broken heart and hair turning orange from dying her hair at home.

The survey was conducted across the U.S. by research firm Harris Interactive on behalf of Careerbuilder and covered nearly 2,500 human resource professionals and around 4,000 workers across industries and company sizes.

The survey further found that 31 per cent of employers notice an uptick in sick days around the winter holidays.

December is the most popular month to call in sick, with 20 per cent saying their employees call in the most during that month. July is the next most popular month to skip out on work, followed by January and February, it said.

The study said that next to actually being sick, the most common reasons employees call in sick are because "they just don't feel like going to work (34 per cent), or because they felt like they needed to relax (29 per cent)."

Others take the day off so they can make it to a doctor's appointment (22 per cent), catch up on sleep (16 per cent), or run some errands (15 per cent).