Drug and Driving: A Compendium of Research Studies

Annotated Sources (cont'd)


54. Alvarez, F. J. (2004)

Medicinal drugs and driving among Spaniards: Data from national survey. In J. Oliver, P. Williams and A. Clayton (Eds.) Proceedings of the 17th International Conference on Alcohol, Drugs and Traffic Safety(CD). Glasgow: Scottish Executive.


Self report survey of medication use among Spanish drivers

Type of study, population(s) and proportion tested

Survey of 2,000 Spanish drivers, who attended one of 23 official driver testing centres in different parts of Spain, in order to undergo an evaluation of their psycho-physical capacity to drive

1,297 males and 703 females
Ages 14 - 69

Drugs examined
  • Medicinal drugs
  • Alcohol
Method of testing and medium used


Dependent variables

Sociodemographic aspects and driving patterns

Self-evaluation of health status

Pathological processes:

  • Different illnesses suffered
  • Whether driver had to stop driving or change driving patterns due to illness
  • Whether driver was warned by doctor about effects of illness on their ability to drive

Pattern of medicinal drugs taken:

  • What drugs were being taken at time of interview
  • Duration of treatment
  • Who prescribed the medication
  • If driver believed the medication affected their ability to drive
  • Whether doctor warned driver to not drive while taking the medication
  • Whether the driver had taken alcohol while taking the medication

Alcohol and illicit drug consumption patterns

Findings (including statistical methods)

Statistical methods were not mentioned

16% suffer some kind of pathological process (no difference between sexes though the reporting of an illness was more frequent as age increased, especially after 40)

83% of these drivers did not change their driving patterns because of the illness, though 25% of them had been warned by their health professional about the effects of their illness on their driving ability

17% (335 drivers) were taking some form of medication at the time of interview (more females reported this than males (18% versus 16%) and more frequently reported as age increased)

These 335 drivers were taking a total of 465 different medications, with majority (68%) only taking one

The mean number of medications increased with age

The majority of medications taken were for chronic illness (376) (this increased with age) and the remainder for acute illness

The majority of the medications were prescribed by doctors (82%)

Most frequently consumed medications were from the "therapeutic groups of alimentary tract and metabolism" (20%), followed by cardiovascular system (19%), and then central nervous system (15%)

91% believed the medication did not affect their ability to drive

The majority had not received warnings from their doctor about the effects of the medication on their ability to drive (79%)

The majority tried to not consume alcohol while taking the medication (79%)


Study documents medication use patterns in relation to driving but no evidence of drug-impaired driving

55. del Rio, C.M., and Alvarez, F. J. (2000)

Presence of illegal drugs in drivers involved in fatal road traffic accidents in Spain. Drug and Alcohol Dependence, 57: 177-182.


Study of drug tests among fatally injured drivers in Spain

Type of study, population(s) and proportion tested

285 fatally injured drivers in Spain

Time period of January 1994 to October 1996

Drugs examined
  • Benzodiazepines
  • Cocaine
  • Cannabis
  • Opiates
  • Amphetamines
  • Synthetic drugs
  • Hallucinogenic drugs
Method of testing and medium used

Blood samples taken within 8 hours of victim’s death

Other dependent variables


Findings (including statistical methods)

Illegal drugs in 10% of cases, alcohol in 51%, and medicines in 9%

8% had illegal drugs with other substances (4% with alcohol)

Cocaine (7%) most frequently detected, followed by opiates (5%), then amphetamines and cannabis (both with 1.4%)

Of those with illegal drugs, 20% with alcohol as well

Most common illegal drug in combination with alcohol was cocaine (57% of the above 20%)


No indication of how cases were selected for inclusion or what proportion of cases were tested

Date modified: