There are a number of resources which practices could use to calculate the capacity required to ensure good telephone response. The following Links direct you to these resources.
These are external links which the Foundation has no control or influence on.
The Danish mathematician Agner Krarup Erlang – an expert in telephone systems – devised the standard formula used for calculating the maximum number of calls per hour that can be handled by a given number of agents (receptionists/call-handlers) given an average call length and the service level that is desired. We have provided below some links to resources that are available on the web. We do not provide any guarantee or recommendation for any of the sites and you will find others by searching for Erlang calculators, but we hope that these are useful to you.
Link 1. Department of Mathematics, Amsterdam University. http://www.math.vu.nl/~koole/ccmath/ErlangC/index.php. This takes you to an on-line calculator that will calculate the service level. Fill in the average call volume for an hour (arrivals), the average length of the call (service time) and the number of staff devoted to answering the phones (number of agents). We also recommend that you fill in the bottom right box with 30 seconds so as to calculate the percentage of calls that will be answered in 30 seconds – as a guide the National standard for out of hours services is that 95% of calls should be answered in 30 seconds, a value below 90% in 30 seconds is generally thought unacceptable by telephone call-centre experts.
Link 2 and 3. Free add-ins for excel. http://www.erlang.co.uk/excel.htm This add-in will allow the calculation of service level given a number of agents or the number of agents required to deliver a particular service level and you can build the formulae into an excel model. Alternatively there is a free calculator provided by call centre helper.com at http://www.callcentrehelper.com/erlang-c-calculator-2473.htm
Link 4. There is a freeware version of cc-modeler professional known as cc-modeler lite at http:www.kooltoolz.comccm.htmgclid=CJbU1vm8vZQCFQKaFQod1ChLTg.
Again this will allow the calculation of service level given a certain number of agents or the calculation of the number of agents needed to deliver a particular service level.
Link 5. For the mathematically minded the formulae are provided at: http://www.mitan.co.uk/mainerlg_spsh.htm Here they also describe how the various formulae can be written into excel.
Link 6. Wikipedia provides an overall description of the Erlang formula and what it does at: http://en.wikipedia.org/wiki/Erlang_unit#Erlang_C_formula
The Primary Care Foundation was established to support the development of best practice in primary and urgent care. The three Directors bring different skills and perspectives to understanding primary and urgent health care - for more details click below:
We also work with a number of associates
The benchmark of out of hours services has been published. To interact with the data and download reports CLICK HERE. To read the overall analysis of the findings CLICK HERE. The benchmark covers more than two thirds of the PCT areas in England and, for the first time, participants have agreed that the data should be published in a way that allows individual services to be identified. To read the press release CLICK HERE.
Rick Stern is to take up the role of Chief Executive of the NHS Alliance from 16 April 2012. He will still be working for half the week as a Director of the Primary Care Foundation
Our latest report ‘Breaking the mould without breaking the system: new ideas and resources for clinical commissioners on the journey towards integrated 24/7 urgent care’ is now available to download CLICK HERE. It is published in partnership with the NHS Alliance and will be formally launched at a session at the NHS Alliance annual conference in Manchester on 1st December 2011.
We are working with increasing numbers of practice to improve access and urgent care in general practice. If you would like to know more about our web based tool and customised reports based on a week of practice data and join over 300 practices across the UK,please email Rick Stern at rick.stern@primarycarefoundation.co.uk
For an independent view of our work with practices on access and urgent care CLICK HERE for the article in the HSJ on 24th November 2011
4th round of the out of hours benchmark. You should be receiving final data for validation soon and the first open set of openly available results will be available from this website in April 2012.