November 2006 1 TRB 2012 DRUID session Drug Driving Enforcement Marjan Hagenzieker and Sjoerd Houwing

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TRB 2012 DRUID session

Drug Driving Enforcement

Marjan Hagenzieker and Sjoerd Houwing

www.swov.nl

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Partners

KLPD (NL)

DTU (DK)

THL (FI)

SWOV (NL)

UGent (BE)

TØI (NO)

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Introduction

Drugs and driving is a serious road safety problem.

Before 2006 only a few EU member states had specific legislation for drugs and driving.

Urine screening devices were used to detect the presence of a specific drug.

Now oral fluid screening devices are the standard. They were evaluated in the ROSITA 2 project (2003-2005), but have they improved since then?

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Main objectives

To get more insight in the usability of oral fluid screening devices

To get more insight in the reliability of oral fluid screening devices

To get more insight in the cost effectiveness of drug driving enforcement

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Practical evaluation• Evaluation of 13 oral fluid screening devices from an

operational police perspective by 10 different police teams

in 6 European countries.

• All devices were tested by each of the 10 police teams.

• Devices were evaluated on 6 items:

• Succesful test performance

• Duration sample collection

• Duration sample analysis

• Hygienic aspects

• Impression reliability

• Simplicity of the test

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Practical evaluation

8 devices have been qualified as promising:

Mavand RapidSTAT Securetec Drugwipe 5+

Branan Oratect XP Varian Oralab 6

Innovacon OrALert Cozart DDS

Dräger Drug Test 5000 Biosensor BIOSENS*

* During specific enforcement activities where a great number of persons should be tested in a limited period of time.

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Promising Oral fluid screening devices

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Analytical evaluation

• Study population consisted of randomly selected drivers from the DRUID roadside survey, suspected drivers, patients of rehabilitation clinics and treatment centres, and customers of coffeeshops.

• Devices were evaluated on: sensitivity, specificity, accuracy

FNTP

TPySensitivit

FPTN

TNySpecificit

FNFPTNTP

TNTPAccuracy

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Substance Sensitivity Specificity Accuracy

Cannabis 11-59% 90-100% 84-98%

Amphetamines 0-87% 90-100% 84-98%

Cocaine 13-50% 99-100% 86-100%

Opiates 69-90% 81-100% 75-99%

Benzodiazepines 48-67% 94-100% 77-100%

Desired target value: 80% for sensitivity and specificity for all substances

Not met by any of the devices!

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In practice the police would rather be interested in the overall sensitivity:

If a driver is positive for a specific drug or combination of drugs, any positive screening result is regarded as a true positive result.

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Task 3.2

Overall sensitivity vs. overall specificity

Only DrugTest 5000, RapidSTAT, and Drugwipe 5+ are above the 80% for sensitivity and specificity

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Evaluation preselection test

Evaluation checklist of Clinical Signs of Impairment (CSI)

• Very low correlation between signs and symptoms and actual presence of drugs. Mainly in high concentrations or very recent use.

• Pupil reaction test was best predicting parameter, esp. for AMP and THC.

• Sensitivity of the checklist was 32%. For signs and symptoms only even lower: 13%.

• More experience, better training, and selection of time and locations with high incidence may improve the results of the CSI.

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• Societal cost-benefit analysis (CBA)

Costs of increased enforcement

Benefits of reduced casualties (valuation of prevented fatalities/injuries/damage) due to increased enforcement

Cost-Benefit Analysis

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An increase of drug driving enforcement should not result in a decrease of drink driving enforcement

Main conclusions CBA #1

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Oral fluid screening devices that perform above average have a higher Benefit-Cost ratio than devices that perform below average


Figure: BC ratios for three quality groups of devices

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Drug driving enforcement is potential beneficial, particularly for countries that currently have a low enforcement level


Netherlands Belgium FinlandBaseline number of drug tests per 100.000 inhabitants

6 36 145

Net benefits 50% increase 5,407,268 11,844,255 438,494

BC ratio 50% increase 19.6 8.04 1.27

Net benefits tripling 13,220,740 27,232,590 -1,335,197

BC ratio tripling 13.74 5.09 0.79

Net benefits 10-fold increase 18,297,599 24,429,424 -21,124,469

BC ratio 10-fold increase 5.04 1.82 0.28

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Summary

Eight of the thirteen evaluated devices were evaluated as promising from an operational police perspective.

None of the promising oral fluid screening devices was very sensitive for all substances. But the usability of a device depends on the prevalence of the target population. Drug-driving enforcement should not go at cost of alcohol enforcement.

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Answer to the question

Did oral fluid screening devices improve since the ROSITA II study?

• From an operational police perspective they did.

• But from an analytical point of view there was hardly any improvement of performance

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More information

www.druid-project.eu

D3.1.1 Evaluation of oral fluid Screening devices by TISPOL to Harmonise European police Requirements (ESTHER)

D3.2.1 Protocol of “workshop on drug driving detection by means of oral fluid screening

D3.2.2 Analytical evaluation of oral fluid screening deivces and preceding selection procedures

D3.3.1 Cost-benefit analysis of drug driving enforcement by the police

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Thank you for your attention!

Documents

November 2006 1 TRB 2012 DRUID session Drug Driving Enforcement Marjan Hagenzieker and Sjoerd Houwing