Last Updated: 03/13/2019

Random Selection Service / Random Selection Procedure

The Random Selection procedure generates the random selections for the pool in specified period of time – selection period.

Med-Stop Random Selection service is based on computer software algorithm that assures the validity of the selection process.

Initial selection is generated on every selection period start for example on the first day of the quarter. During the selection period the pools are recalculated daily to update the pool statistics based on completed selections and to compensate the average number of pool member changes. Some additional selections can be generated when the average number of pool members is higher then on the period start to assure that the total number of generated random selections allows to complete the pool target.

The Med-Stop Random Service selection procedure consists following steps:

Pool Statistics Update – the pool completed selections and tests are counted, the average number of pool members is recalculated and based on this the pool current percentage is updated.

Calculation of the required number of selections in the selection period – to make sure the random selections are spread equally in the period determined by the pool earliest and latest selection dates – usually the whole calendar year – the selection period target percentage is determined. For example if the pool covers the whole calendar year and the selection period is set to be quarter – there are 4 quarters in the year. The pool target percentage is divided by the number of periods and the number of selections in this period is calculated based on this period percentage and current average number of pool members.

Verification of the number of open and completed selections in the selection period – having the number of required selection in the selection period allows to verify that the random selections that are already generated meets the number of required ones. In the beginning of the selection period, when there is no already available selections are required selections are performed. During the period – some may be added when the average number of pool members goes high.

It is very important to remember that you cannot complete the open selections from the previous selection periods to satisfy the random selection procedure. When the random selection is not completed in the period it was generated – it cannot be closed in next periods – it is not counted for the pool target percentage even if the test is completed.

Random selection procedure creates new selections to cover the ones that were not completed in previous selection periods.

Reserve Selections validation – the reserve, alternate selection is generated to have a replacement selection for the ones that were canceled during the selection period. The number of reserve selections is set to be 10% of all required selections in the selection period but no more then 5. The reserve selections have always the selection date set to the last day of the selection period, and cannot be used as long as they are not specified as a replacement for the canceled selection. For example when you terminate the employee that was selected for the random testing, his/her random selection is canceled and the first available reserve selection is activated. It is important to remember that you as a company safety officer can specify any date for this reserve selection – the date that falls in the current selection period. They do not have to be done on the last day of the selection period.

Creating required Random Selection – when the algorithm determines that some new random selections needs to be generated for current selection period it performs following steps:

-        selects randomly the date that is between the current selection period start and end dates – the date is generated by adding the random number of days from the 5 days from the selection period start date. The 5 days period is selected to assure that the random selection dates are not generated on the same day as the selection occurs as this could not allow you to properly schedule random test and notify the employee.

-        selects randomly the pool member id – the pool members have a computer system, randomly assigned id’s that cannot be sorted in any specific order. The selection procedure randomly selects the id from the list of the pool members. Every time the selection is made all pool members have the equal chance to be selected.

-        the random selection is recorded: pool service, the date and pool member id determine the selection information

The steps are repeated as many times as many new random selections are required.

Recording the selection history – when the random selection is completed all parameters of the selection are recorded in the pool history. Every new selection that was made is also recorded in the pool history.

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