Use of Cookies by this Site

As explained in our privacy policy, "cookies" and similar technologies enable a website to work, or work more efficiently, as well as provide information and additional services. This page explains the use of cookies and similar tools set by the Elsevier corporate website at, the Elsevier support website at and the Elsevier journals website at

The tables below explain the main cookies set by these sites and their purpose.

ServiceCookie NamePurposeMore Info
 Site Server SITESERVERThis session cookie, provided by Microsoft, creates more accurate visitor logs.

ServiceCookie NamePurposeMore Info
 RightNow CX cp_sessionThis session cookie, provided by RightNow Technologies, Inc., maintains session data for security purposes.

ServiceCookie NamePurposeMore Info ASP.NET_SessionIdThe session cookie, set by digital publisher PageSuite Limited, is used for monitoring load balancing between PageSuite's servers while you are linked to the website, to conduct analyses of user traffic, and to perform web log audits.See Microsoft Support website


The table below explains the unique cookie set by these sites and its purpose.

ServiceCookie NamePurposeMore Info
Elsevier surveyElsevierSurvThis cookie is used to ensure that visitors who have already taken a survey are not offered the same survey again


The table below explains the web analytics cookies set by these sites and their purpose.

ServiceCookie NamePurposeMore Info
Google Analytics with Display Advertising, Google Remarketing and Google DoubleClickCookies which names begin with _utThese web analytics cookies, provided by Google Inc., are used to collect information about how visitors use our site. We use the information to compile reports and to help us improve the site. In addition we use first-party cookies (such as the Google Analytics cookie) and third-party cookies (such as the Google DoubleClick cookie) together to inform, optimise and serve ads based on someone's past visits to our website and report how ad impressions, other uses of ad services and interactions with these ad impressions and ad services are related to visits to our site.

See Cookies Set by Google Analytics and Google Analytics Privacy Overview.

To find out about DoubleClick cookies and how to control those cookies, go to

 If you do not wish to allow the use of Google Analytics for advertising, you can opt out using the Google Ad Settings: 

If you do not wish to allow the use of Google Analytics cookies at all, Google provides an opt-out plug-in for most common website browsers

CrazyEggis_returningThis cookie is used to determine whether the user is new or returningSee


The table below explains the web analytics cookies set additionally on and their purpose.

ServiceCookie NamePurposeMore Info
Digital Analytixs1, ns_session, ns_cookietestThese web analytics cookies (formerly SiteStat), provided by comScore Inc. (formerly NedStat), are used to gather information regarding visitor activity and determine whether cookies are enabled. The s1 cookie contains a unique alpha-numeric value to help accurately estimate the number of visitors to the site and volumes of usage.See comScore Privacy Policy


The tables below explain the cookies presented by third parties to support the functionality of their widgets, such as 'Like' and 'Share' buttons, placed on these sites:

ServiceCookie NamePurposeMore Info
Google MapsSNID, NID, PREFThese cookies are used by Google to store user preferences and information when viewing pages with Google maps on them.See Google Privacy Policy
Survey Monkeyep201, ep202, TS54026eWe make use of surveymonkey software to carry out a number of surveys across this website. These cookies are used to identify whether or not visitors have completed the survey or not, or in previous visits have selected not to complete a survey.

ServiceCookie NamePurposeMore Info
Twitterguest_id, twll, k, _twitter_sess, original_referer, external_refererThese cookies, provided by Twitter, are used in conjunction with the Twitter social plugins in order to allow following our Twitter accounts easily, share content via Twitter, and to display the latest tweet. Twitter makes use of cookies to improve its own service.See Twitter Privacy Policy
AddThisdi/dt, psc, uid/uit, uvc, siteaud, ana_svc, loc, ssc, ssh, sshs, uvc, xtc, _canary, _mpush, _xgcid, _xguidThese cookies, provided by Clearspring Technologies, Inc., are used in conjunction with the AddThis Button to enable you to share our content through email, social networking sites, blogs and more.See AddThis Privacy and Data Practices


Option to decline use of cookies

You can prevent your browser from accepting certain cookies, have the browser require your consent before a new cookie is placed in your browser, or block cookies altogether by selecting the appropriate settings on your browser's privacy preferences menu.  To avoid receiving cookies on the browser of your mobile device, you will need to refer to its user manual.  For information on how to opt-out of cookies set by our suppliers, please visit the applicable links listed in the tables above.


Last revised: 6 June 2012