As a result of the controversy that drug screening invaded personal space, most companies are now insisting on employing MRO services to ensure that the results of the test are accurate.

MRO services provide the service of medical review officer to analyze the results of a drug test. Since the MRO is usually a physician, the results of the drug screening test are more accurate.

The role of the Medical Review Officer in drug screening is to interpret laboratory results obtained through the drug screening. The MRO's services are important safeguards in the testing process. MRO services assure respect for personal confidentiality and dignity of the donor, maintenance of the confidentiality of medical information, maintenance of high scientific and medical standards

The reason that drug screening is being insisted on by most companies these days is because Federal Government studies show that 6 per cent of employed individuals use drugs.

Research has also indicated that drug use could lower the company's productivity, compromise its security and lead to higher absenteeism and job turnover. Drug users are 2.5 times more likely to have more absent days and 3.6 times more likely to be involved in a work accident.

Drug screening by a company can be done on-site or at a laboratory. Most large firms prefer to have pre employment assessment and drug screening done at laboratories so that the results can be obtained more accurately.

The pre employment drug testing kits can be purchased at regular stores or at laboratories. With most drug screening kits, employers can screen for several drugs including cocaine, methamphetamines, ecstasy, marijuana and hashish. Some pre employment drug screening panels can also check for alcohol addiction.

The most accurate drug testing kits rely on hair samples. For most drug screening, samples of hair should be at least 1.5 inches long and there should be enough hair samples to fit the diameter of a straw.

Different drug screening tests have different cut off levels for detecting drugs. The number of days that a drug will stay in the blood stream differs from person to person. The levels of drugs that can be detected depend on the sensitivity of the test.

Most employers choose to send their prospective employees to laboratories for the pre employment drug screening. The reason for this is that drug tests are more reliable when reviewed by a medical review officer.