To the editor:
To obtain the best possible therapeutic outcome, patient compliance is crucial. When patients fail to understand their diagnosis and treatment plan, they are prone to noncompliance, resulting in subtherapeutic outcomes and drug-related toxicity. Moreover, poorly compliant patients have a greater incidence of unscheduled physician office, urgent care, and emergency room visits.1 Obviously, this excessive use of the health care system results in increased expenditures.
Patient noncompliance is complex and influenced by many factors, including patient socioeconomic status, motivation, psychological and physical well-being, frequency of dosing, and literacy.2 Often forgotten in the reasons for noncompliance is the patient lack of understanding of clinician instructions. Several studies have found that effective clinician-patient communication significantly enhances patient compliance.3'5
The volume of a liquid medication to be administered is an important aspect of drug therapy. This is especially true in children, for whom dosage is determined by body weight, which varies greatly among patients. Further, the drug utilized may have a narrow therapeutic index, and misinterpretation of the volume administered may result in a subtherapeutic or toxic serum concentration. It is crucial, therefore, that the parent who usually administers the medication understand the precise volume of drug ordered.
Because pediatrie medications are routinely written with measurements in teaspoonfuls, we investigated whether caregivers could select a teaspoon from a group of spoons. Choices included a sugar spoon (2.5 mL), teaspoon (5 mL), dessert spoon (10 mL), and tablespoon (15 mL). One hundred sixty-two parents were evaluated at San Joaquín County Hospital Pediatrie Acute Care Clinic, which services lower socioeconomic patients with low literacy rates. After children were evaluated by a physician, prescriptions for liquid mediation written, and directions for administration explained, parents were asked to select the teaspoon from the group of four spoons. Of the parents interviewed, only 38.3% correctly identified the teaspoon. The most commonly erroneously chosen spoon was the tablespoon (60%), which represents three times the prescribed dose.
One possible solution to this problem requires patient utilization of a dosing spoon, which typically retails for approximately three dollars. Unfortunately, patients from lower socioeconomic groups may be less likely to purchase dosing spoons than those of higher economic standing. This study illustrates the need for clinicians to ascertain patient understanding of dosing instructions. It should be emphasized that a patient who does not comprehend the administration instructions for a medication cannot be expected to comply with those instructions.
Paid G Ambrose, PharmD
Michael J. Garvey, PharmD
Clifton Springs, New York
Berit Gunderson, PharmD
Richard Quintilioni, MD
1. Cai N, Fanale JE, Kronholm P. The role of Medication noncompliance and adverse drug reactions in hospitaliiations of the elderly. Arch intern Mea. 1990; 150:841845.
2. Mayeaux EJ, Murphy PW. Arnold C, Davis TC. Jacbon RH, Sentell T. Improving patienE education for patients with low literacy skills. American Family Physician. 1996; 53:205-211.
3. Borgsdorf LR, Maino JS, Knapp KK. Pharmacist-managed medications review in a managed care system. American Journal o/Hojpuul Pharmacy. 1994; 51:772-777.
4. Sczupak CA, Conrad WF Relationship between patient oriented pharmaceutical services and therapeutic outcomes of ambulatory patient* with diabetes mellicui. Ammern Joiimal of Hospsal Pharmacy. 1977; 34:1238-1242.
5. Hanchale NA, Pare! MB, Berlin J A, Strom BL. Patient misunderstanding of dosing instructions. Journal of General internal Mtdame. 1996; 11:325-318.
Dr. ALtemeier responds:
It is amazing how frequently parents make errors in dispensing medications. We often assume that when we give a family a prescription and a few words about what we want the patient to receive, the child will get the correct dose. But many reports have demonstrated otherwise. McMahon, Rimsza, and Bay1 summarized this recently as part of a study designed to find a more effective way to get the correct amount of medicine into a child. They listed the steps that can go wrong between giving the parent a prescription and this. Included were using outdated or unrefngerated medications, confusing the child and infant acetaminophen preparations, vomiting, spitting, spilling, and leaving some medication in the dispenser. These authors reference four reports that demonstrate the inaccuracy of dosing when medications are prescribed by the teaspoon and three other reports (beside the one presented above) that show that parents are commonly confused about what is a teaspoon. McMahon and colleagues went on to search for a better way. They compared accuracy by observing what parents gave after receiving a prescription and verbal dosing directions (group 1), a syringe and a demonstration of how to give a dose (group 2), or a demonstration of use of a syringe with a line drawn from the needle end to a circle drawn at the correct dose (group 3). Only 37% of group 1 received the correct amount (rather stringently defined as ± 0.2 mL, though the range of incorrect doses was 32% to 147%). Group 2 had an 83% accuracy, whereas group 3 was 100% on the mark. The authors point out the problems of cost, choking, and bubbles in using a syringe for oral dosing. But the main conclusion of many such studies is that a significant proportion of parents will give the wrong dose if you send them away with a prescription and a sentence about what you want the child to receive.
1 . McMahon SR. Rimsia ME, Bay RC. Patents can dose liquid medication accurately- Pediatrics. 1997; lOOi330-333.