Authors

  1. Lindsey, Heather

Article Content

According to this study:

 

* Nearly half of patients misunderstood dosing instructions on labels of commonly prescribed drugs.

 

* Many patients who correctly stated instructions couldn't correctly demonstrate the number

 

* of pills to be taken daily.

 

* More than one-third with an adequate level of literacy made errors.

 

 

A new study of primary care patients found that 46% of patients interviewed were unable to read and correctly state one or more instructions on the label of a commonly prescribed medication.

 

Researchers conducted a cross-sectional study using in-person, structured interviews of 395 English-speaking adults (mean age, 45 years) waiting to see their providers at three clinics serving mostly indigent populations in Shreveport, Louisiana; Jackson, Michigan; and Chicago.

 

Interviewers assessed patients' understanding of instructions on five container labels: amoxicillin and trimethoprim (antibiotics), guaifenesin (an expectorant), felodipine (an antihypertensive), and furosemide (a diuretic). Responses were scored as either right or wrong.

 

As part of a secondary study, patients were given candy pills to demonstrate how they would take guaifenesin. Patient literacy was also evaluated using a word-recognition test with 66 health-related words.

 

Researchers found that correct understanding of the five labels ranged from 67% to 91%. Patients with a low literacy level, defined as reading at or below the sixth-grade level, were less able to understand all five label instructions. Although 71% of patients with a low literacy level correctly stated the instructions-"Take two tablets by mouth twice daily"-only 35% could accurately demonstrate the number of pills to be taken daily. Low and marginal literacy levels were statistically significant independent predictors of misunderstanding. But 38% of patients with adequate literacy skills also misunderstood at least one of the label instructions.

 

"This is cause for concern," write the study authors, "because patient misunderstanding could be a [horizontal ellipsis] source of medication error." They conclude that patients would benefit from additional efforts to improve the clarity and comprehensibility of labeling on prescription drugs.

 
 

Davis TC, et al. Ann Intern Med 2006; 145(12):887-94.