Effect on Antibiotic Prescribing of Repeated Clinical Prompts to Use a Sore Throat Score

,

Original Research

Effect on Antibiotic Prescribing of Repeated Clinical Prompts to Use a Sore Throat Score

J Fam Pract. 2002 April;51(4):339-344

By

Warren J. McIsaac, MD, MSc

Lessons from a Failed Community Intervention Study

PDF Download

References

1. Seppälä H, Nissinen A, Järvinen H, et al. Resistance to erythromycin in group A streptococci. N Engl J Med 1992;326:292-7.

2. Chen DK, McGeer A, de Azavedo JC, Low DE. Decreased susceptibility of Streptococcus pneumoniae. to fluoroquinolones in Canada. N Engl J Med 1999;341:233-9.

3. Magee JT, Pritchard EL, Fitzgerald KA, Dunstan FDJ, Howard AJ. Antibiotic prescribing and antibiotic resistance in community practice: retrospective study, 1996-8. BMJ 1999;319:1239-40.

4. Arason VA, Kristinsson KG, Sigurdsson JA, Stefánsdóttir G, Mölstad S, Gudmundsson S. Do antimicrobials increase the carriage rate of penicillin rate of penicillin resistant pneumococci in children? Cross sectional prevalence study. BMJ 1996;313:387-91.

5. Seppälä H, Klaukka T, Vuopio-Varkila J, et al. The effect of changes in the consumption of macrolide antibiotics on erythromycin resistance in Group A streptococci in Finland. N Engl J Med 1997;337:441-6.

6. Bass JW, Weisse ME, Plymyer MR, Murphy S, Eberly BJ. Decline of erythromycin resistance of Group A beta-hemolytic streptococci in Japan. Arch Pediatr Adolesc Med 1994;148:67-71.

7. Wise R, Hart T, Cars O, et al. Antimicrobial resistance is a major threat to public health. BMJ 1998;317:610-11.

8. Schwartz B, Bell DM, Hughes JM. Preventing the emergence of antimicrobial resistance. A call for action by clinicians, public health officials, and patients. JAMA 1997;278:944-5.

9. McCaig LF, Hughes JM. Trends in antimicrobial drug prescribing among office-based physicians in the United States. JAMA 1995;273:214-9.

10. Gonzales R, Steiner JF, Sande MA. Antibiotic prescribing for adults with colds, upper respiratory tract infections, and bronchitis by ambulatory care physicians. JAMA 1997;278:901-4.

11. Nyquist AC, Gonzales R, Steiner JF, Sande MA. Antibiotic prescribing for children with colds, upper respiratory tract infections, and bronchitis. JAMA 1998;279:875-7.

12. Brumfit W, O’Grady F, Slator JDH. Benign streptococcal sore throat. Lancet 1959;2:419-23.

13. Little PS, Williamson I. Are antibiotics appropriate for sore throats? Costs outweigh benefits. BMJ 1994;309:1010-2.

14. Graham A, Fahey T. Sore throat: diagnostic and therapeutic dilemmas. BMJ 1999;319:173-4.

15. Dajani A, Taubert K, Ferrieri P, Peter G, Shulman S. Treatment of acute streptococcal pharyngitis and prevention of rheumatic fever: A statement for health professionals. Pediatrics 1995;96:758-64.

16. Bisno AL, Gerber MA, Gwaltney JM, Kaplan EL, Schwartz RH. Diagnosis and management of group A streptococcal pharyngitis: a practice guideline. Clin Infect Dis 1997;25:574-83.

17. Hart WJ. Streptococcal pharyngitis. A demonstration of the inaccuracy of clinical diagnosis without culture. Can Fam Physician 1976;22:34-9.

18. Shank JC, Powell TA. A five-year experience with throat cultures. J Fam Pract 1984;18:857-63.

19. McIsaac WJ, White D, Tannenbaum D, Low DE. A clinical score to reduce unnecessary antibiotic use in patients with sore throat. CMAJ 1998;158:75-83.

20. Touw-Otten FWMM, Johansen KS. Diagnosis, antibiotic treatment and outcome of acute tonsillitis: report of a WHO regional office for Europe study in 17 European countries. Fam Pract 1992;9:255-62.

21. Poses RM, Cebul RD, Collins M, Fager SS. The accuracy of experienced physicians’ probability estimates for patients with sore throats. Implications for decision making. JAMA 1985;254:925-9.

22. McIsaac WJ, Butler CC. Does clinical error contribute to unnecessary antibiotic use? Med Decis Making 2000;20:33-8.

23. Walsh BT, Bookheim WW, Johnson RC, Tompkins RK. Recognition of streptococcal pharyngitis in adults. Arch Intern Med 1975;135:1493-7.

24. Breese BB. A simple scorecard for the tentative diagnosis of streptococcal pharyngitis. Am J Dis Child 1977;131:514-17.

25. Centor RM, Witherspoon JM, Dalton HP, Brody CE, Link K. The diagnosis of strep throat in adults in the emergency room. Med Decis Making 1981;1:239-46.

26. Fujikawa S, Ito Y. A new scoring system for diagnosis of streptopharyngitis. Jpn Circ J 1985;49:1258-61.

27. Komaroff AL, Pass TM, Aronson MD, et al. The prediction of streptococcal pharyngitis in adults. J Gen Intern Med 1986;1:1-7.

28. Hoffman S. An algorithm for a selective use of throat swabs in the diagnosis of group A streptococcal pharyngo-tonsillitis in general practice. Scand J Prim Health Care 1992;10:295-300.

29. Meland E, Digranes A, Skjærven R. Assessment of clinical features predicting streptococcal pharyngitis. Scand J Infect Dis 1993;25:177-83.

30. Dobbs F. A scoring system for predicting group A streptococcal infection. Br J Gen Pract 1996;46:461-4.

31. Poses RM, Cebul RD, Wigton RS. You can lead a horse to water: improving physicians’ knowledge of probabilities may not affect their decisions. Med Decis Making 1995;15:65-76.

32. McIsaac WJ, Goel V, To T, Low DE. The validity of a sore throat score in family practice. CMAJ 2000;163:811-5.

33. McIsaac WJ, Goel V. Effect of an explicit decision-support tool on decisions to prescribe antibiotics for sore throat. Med Decis Making 1998;18(2):220-8.

34. Davis DA, Thomson MA, Oxman AD, Haynes RB. Changing physician performance. A systematic review of the effect of continuing medical education strategies. JAMA 1995;274:700-5.

35. Rosser WW, McDowell I, Newell C. Use of reminders for prevention procedures in family medicine. CMAJ 1991;145:807-13.

36. Ukoumunne OC, Gulliford MC, Chinn S, Sterne JAC, Burney PGJ, Donner A. Evaluation of health interventions at area and organisation level. BMJ 1999;319:376-9.

37. Rogers S, Humphrey C, Nazareth I, Lister S, Tomlin Z, Haines A. Designing trials of interventions to change professional practice in primary care: lessons from an exploratory study of two change strategies. BMJ 2000;320:1580-3.

ABSTRACT

OBJECTIVES: Infections with group A streptococcus (GAS) occur in 10% to 20% of patients with sore throats, whereas antibiotics are prescribed 50% of the time. Clinical scoring rules can more accurately predict the likelihood of GAS infection, but whether family physicians will adopt such approaches is unclear. This study sought to determine whether repeated clinical prompts to use a scoring approach could help family physicians lower antibiotic use in patients with a sore throat.

STUDY DESIGN: Randomized trial in which physicians were assigned to use either (1) chart stickers that prompted them to calculate a score based on clinical findings and provided management recommendations linked to score totals or (2) a clinical checklist.

POPULATION: Ninety-seven family physicians in Ontario, Canada, assessed 621 children and adults with sore throat and obtained a throat swab for culture.

OUTCOMES MEASURED: (1) Unnecessary antibiotic prescriptions given to patients with a negative throat culture and (2) overall antibiotic use.

RESULTS: There were no differences between the control and intervention group in unnecessary antibiotic prescriptions (16.1% vs 20.4%, respectively, P = .29) or overall antibiotic use (27.9% vs 28.1%, P = .97). However, a number of physicians dropped out of the study; as a result, the characteristics of the physicians in the 2 groups were dissimilar in factors related to prescribing. After adjusting for these differences and patient clustering by physician, the odds ratio for the effect of the intervention on unnecessary antibiotic prescriptions was 0.76 (95% confidence interval [CI] = 0.42, 1.40) and 0.57 for overall antibiotic use (95% CI = 0.27, 1.17).

CONCLUSIONS: Chart prompts during clinical encounters to use a clinical score in the assessment of patients with a sore throat did not reduce unnecessary antibiotic prescribing by family physicians. The problems encountered in conducting this community-based intervention trial are discussed in relation to the negative result.

KEY POINTS FOR CLINICIANS

Repeated chart prompts to use a clinical prediction rule for the management of children and adults with a sore throat did not help family physicians decrease unnecessary antibiotic use.
Several problems in the conduct of this community-based intervention trial rather than a lack of the effectiveness of the intervention may have contributed to the negative result.

In the past decade, bacterial resistance to commonly used antibiotics has risen dramatically.^1,2 While a number of factors have contributed to this problem, overuse of antibiotics by physicians has been implicated.^3-6 An association has been demonstrated between the volume of antibiotic prescriptions and bacterial resistance at both a national^4,5 and a local level.³ Where prescribing by physicians has been reduced, rates of antibiotic resistance have subsequently been observed to decline.^5,6 As a result, physicians have been urged to reduce their use of antibiotics.^7,8 Respiratory infections are the most common reason for the prescribing of antibiotics.⁹ Upper respiratory tract infections (URTIs) and pharyngitis account for 19% to 28% of all antibiotic prescriptions written by family physicians.^9-11

While the use of antibiotics for URTI with sore throat is frequently debated,^12-14 experts continue to recommend such treatment for group A streptococcus (GAS) infections to prevent rheumatic fever.^15,16 However, only 10% to 20% of patients with a sore throat who visit a family physician have a GAS infection,^17-19 whereas antibiotics are prescribed for 50% of URTIs¹⁰ and 90% of cases of tonsillitis.²⁰ Uncertainty as to whether or not a bacterial infection is present and clinical error in estimating the likelihood of a GAS infection are associated with the unnecessary prescription of antibiotics.^21,22 To address clinical uncertainty, a number of prediction rules and clinical scores have been proposed.^23-30 However, physicians taught simply to generate more accurate estimates of the likelihood of a strep infection in this manner do not necessarily lower their use of antibiotics.³¹

We have previously shown that linking score estimates for the likelihood of a GAS infection to explicit management recommendations to take a throat swab or prescribe an antibiotic has the potential to lower antibiotic use significantly.^19,32 In an observational study involving 621 children and adults, this approach would have reduced unnecessary antibiotic prescriptions by 63%.³² We also found a trend toward reduced antibiotic use when physicians were provided with an explicit reminder about the score approach.³³ As a result, we hypothesized that this might also help physicians to learn to adopt the sore throat score approach. Reminders have been found to improve the delivery of preventive health services.^34,35 The objective of this study was to determine whether repeated clinical prompts to community-based family physicians about the score approach could reduce unnecessary antibiotic prescriptions and lower overall antibiotic use for patients with a sore throat.