Skip to main content
CMAJ : Canadian Medical Association Journal logoLink to CMAJ : Canadian Medical Association Journal
. 1998 Jan 13;158(1):75–83.

A clinical score to reduce unnecessary antibiotic use in patients with sore throat

W J McIsaac 1, D White 1, D Tannenbaum 1, D E Low 1
PMCID: PMC1228750  PMID: 9475915

Abstract

OBJECTIVE: To validate a score based on clinical symptoms and signs for the identification of group A Streptococcus (GAS) infection in general practice patients with score throat. DESIGN: A single throat swab was used as the gold standard for diagnosing GAS infection. Clinical information was recorded by experienced family physicians on standardized encounter forms. Score criteria were identified by means of logistic regression modelling of data from patients enrolled in the first half of the study. The score was then validated among the remaining patients. SETTING: University-affiliated family medicine centre in Toronto. PATIENTS: A total of 521 patients aged 3 to 76 years presenting with a new upper respiratory tract infection from December 1995 to February 1997. OUTCOME MEASURES: Sensitivity, specificity and likelihood ratios for identification of GAS infection with the score approach compared with throat culture. Proportion of patients prescribed antibiotics, throat culture use, and sensitivity and specificity with usual physician care and with score-based recommendations were compared. RESULTS: A score was developed ranging in value from 0 to 4. The sensitivity of the score for identifying GAS infection was 83.1%, compared with 69.4% for usual physician care (p = 0.06); the specificity values of the 2 approaches were similar. Among patients aged 3 to 14 years, the sensitivity of the score approach was higher than that of usual physician care (96.9% v. 70.6%) (p < 0.05). The proportion of patients receiving initial antibiotic prescriptions would have been reduced 48% by following score-based recommendations compared with observed physician prescribing (p < 0.001), without any increase in throat culture use. CONCLUSIONS: An age-appropriate sore throat score identified GAS infection in children and adults with sore throat better than usual care by family physicians, with significant reductions in unnecessary prescribing of antibiotics. A randomized trial comparing the 2 approaches is recommended to determine the ability of the score approach to reduce unnecessary prescribing of antibiotics during routine clinical encounters.

Full Text

The Full Text of this article is available as a PDF (149.7 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Arason V. A., Kristinsson K. G., Sigurdsson J. A., Stefánsdóttir G., Mölstad S., Gudmundsson S. Do antimicrobials increase the carriage rate of penicillin resistant pneumococci in children? Cross sectional prevalence study. BMJ. 1996 Aug 17;313(7054):387–391. doi: 10.1136/bmj.313.7054.387. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bach J. F., Chalons S., Forier E., Elana G., Jouanelle J., Kayemba S., Delbois D., Mosser A., Saint-Aime C., Berchel C. 10-year educational programme aimed at rheumatic fever in two French Caribbean islands. Lancet. 1996 Mar 9;347(9002):644–648. doi: 10.1016/s0140-6736(96)91202-7. [DOI] [PubMed] [Google Scholar]
  3. Breese B. B. A simple scorecard for the tentative diagnosis of streptococcal pharyngitis. Am J Dis Child. 1977 May;131(5):514–517. doi: 10.1001/archpedi.1977.02120180028003. [DOI] [PubMed] [Google Scholar]
  4. Breiman R. F., Butler J. C., Tenover F. C., Elliott J. A., Facklam R. R. Emergence of drug-resistant pneumococcal infections in the United States. JAMA. 1994 Jun 15;271(23):1831–1835. [PubMed] [Google Scholar]
  5. Cebul R. D., Poses R. M. The comparative cost-effectiveness of statistical decision rules and experienced physicians in pharyngitis management. JAMA. 1986 Dec 26;256(24):3353–3357. [PubMed] [Google Scholar]
  6. Centor R. M., Witherspoon J. M., Dalton H. P., Brody C. E., Link K. The diagnosis of strep throat in adults in the emergency room. Med Decis Making. 1981;1(3):239–246. doi: 10.1177/0272989X8100100304. [DOI] [PubMed] [Google Scholar]
  7. Dagnelie C. F., van der Graaf Y., De Melker R. A. Do patients with sore throat benefit from penicillin? A randomized double-blind placebo-controlled clinical trial with penicillin V in general practice. Br J Gen Pract. 1996 Oct;46(411):589–593. [PMC free article] [PubMed] [Google Scholar]
  8. Danjani A. S., Bisno A. L., Chung K. J., Durack D. T., Gerber M. A., Kaplan E. L., Millard H. D., Randolph M. F., Shulman S. T., Watanakunakorn C. Prevention of rheumatic fever. A statement for health professionals by the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease of the Council on Cardiovascular Disease in the Young, the American Heart Association. Circulation. 1988 Oct;78(4):1082–1086. doi: 10.1161/01.cir.78.4.1082. [DOI] [PubMed] [Google Scholar]
  9. Dobbs F. A scoring system for predicting group A streptococcal throat infection. Br J Gen Pract. 1996 Aug;46(409):461–464. [PMC free article] [PubMed] [Google Scholar]
  10. Fujikawa S., Ito Y., Ohkuni M. A new scoring system for diagnosis of streptopharyngitis. Jpn Circ J. 1985 Dec;49(12):1258–1261. doi: 10.1253/jcj.49.1258. [DOI] [PubMed] [Google Scholar]
  11. Hoffmann 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 Dec;10(4):295–300. doi: 10.3109/02813439209014077. [DOI] [PubMed] [Google Scholar]
  12. Holmberg S. D., Faich G. A. Streptococcal pharyngitis and acute rheumatic fever in Rhode Island. JAMA. 1983 Nov 4;250(17):2307–2312. [PubMed] [Google Scholar]
  13. Howie J. G. Clinical judgement and antibiotic use in general practice. Br Med J. 1976 Oct 30;2(6043):1061–1064. doi: 10.1136/bmj.2.6043.1061. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Hutten-Czapski P. Acute rheumatic fever--no epidemic in Ontario. Can J Public Health. 1989 Jan-Feb;80(1):71–72. [PubMed] [Google Scholar]
  15. Kljakovic M. Sore throat presentation and management in general practice. N Z Med J. 1993 Sep 8;106(963):381–383. [PubMed] [Google Scholar]
  16. Mainous A. G., 3rd, Hueston W. J., Clark J. R. Antibiotics and upper respiratory infection: do some folks think there is a cure for the common cold. J Fam Pract. 1996 Apr;42(4):357–361. [PubMed] [Google Scholar]
  17. McGregor A., Dovey S., Tilyard M. Antibiotic use in upper respiratory tract infections in New Zealand. Fam Pract. 1995 Jun;12(2):166–170. doi: 10.1093/fampra/12.2.166. [DOI] [PubMed] [Google Scholar]
  18. McIsaac W. J., Goel V., Slaughter P. M., Parsons G. W., Woolnough K. V., Weir P. T., Ennet J. R. Reconsidering sore throats. Part 2: Alternative approach and practical office tool. Can Fam Physician. 1997 Mar;43:495–500. [PMC free article] [PubMed] [Google Scholar]
  19. McIsaac W. J., Goel V. Sore throat management practices of Canadian family physicians. Fam Pract. 1997 Feb;14(1):34–39. doi: 10.1093/fampra/14.1.34. [DOI] [PubMed] [Google Scholar]
  20. Morise A. P., Diamond G. A., Detrano R., Bobbio M., Gunel E. The effect of disease-prevalence adjustments on the accuracy of a logistic prediction model. Med Decis Making. 1996 Apr-Jun;16(2):133–142. doi: 10.1177/0272989X9601600205. [DOI] [PubMed] [Google Scholar]
  21. Neu H. C. The crisis in antibiotic resistance. Science. 1992 Aug 21;257(5073):1064–1073. doi: 10.1126/science.257.5073.1064. [DOI] [PubMed] [Google Scholar]
  22. Pichichero M. E., Disney F. A., Talpey W. B., Green J. L., Francis A. B., Roghmann K. J., Hoekelman R. A. Adverse and beneficial effects of immediate treatment of Group A beta-hemolytic streptococcal pharyngitis with penicillin. Pediatr Infect Dis J. 1987 Jul;6(7):635–643. doi: 10.1097/00006454-198707000-00004. [DOI] [PubMed] [Google Scholar]
  23. Poses R. M., Cebul R. D., Collins M., Fager S. S. The importance of disease prevalence in transporting clinical prediction rules. The case of streptococcal pharyngitis. Ann Intern Med. 1986 Oct;105(4):586–591. doi: 10.7326/0003-4819-105-4-586. [DOI] [PubMed] [Google Scholar]
  24. Poses R. M., Cebul R. D., Wigton R. S. You can lead a horse to water--improving physicians' knowledge of probabilities may not affect their decisions. Med Decis Making. 1995 Jan-Mar;15(1):65–75. doi: 10.1177/0272989X9501500110. [DOI] [PubMed] [Google Scholar]
  25. Pozen M. W., D'Agostino R. B., Selker H. P., Sytkowski P. A., Hood W. B., Jr A predictive instrument to improve coronary-care-unit admission practices in acute ischemic heart disease. A prospective multicenter clinical trial. N Engl J Med. 1984 May 17;310(20):1273–1278. doi: 10.1056/NEJM198405173102001. [DOI] [PubMed] [Google Scholar]
  26. Quinn K., Baker M. J., Evans B. A population-wide profile of prescription drug use in Saskatchewan, 1989. CMAJ. 1992 Jun 15;146(12):2177–2186. [PMC free article] [PubMed] [Google Scholar]
  27. Quinn R. W. Comprehensive review of morbidity and mortality trends for rheumatic fever, streptococcal disease, and scarlet fever: the decline of rheumatic fever. Rev Infect Dis. 1989 Nov-Dec;11(6):928–953. doi: 10.1093/clinids/11.6.928. [DOI] [PubMed] [Google Scholar]
  28. Randolph M. F., Gerber M. A., DeMeo K. K., Wright L. Effect of antibiotic therapy on the clinical course of streptococcal pharyngitis. J Pediatr. 1985 Jun;106(6):870–875. doi: 10.1016/s0022-3476(85)80228-6. [DOI] [PubMed] [Google Scholar]
  29. Shank J. C., Powell T. A. A five-year experience with throat cultures. J Fam Pract. 1984 Jun;18(6):857–863. [PubMed] [Google Scholar]
  30. Stiell I. G., McKnight R. D., Greenberg G. H., McDowell I., Nair R. C., Wells G. A., Johns C., Worthington J. R. Implementation of the Ottawa ankle rules. JAMA. 1994 Mar 16;271(11):827–832. [PubMed] [Google Scholar]
  31. Taubert K. A., Rowley A. H., Shulman S. T. Nationwide survey of Kawasaki disease and acute rheumatic fever. J Pediatr. 1991 Aug;119(2):279–282. doi: 10.1016/s0022-3476(05)80742-5. [DOI] [PubMed] [Google Scholar]
  32. Tenover F. C., Hughes J. M. The challenges of emerging infectious diseases. Development and spread of multiply-resistant bacterial pathogens. JAMA. 1996 Jan 24;275(4):300–304. [PubMed] [Google Scholar]
  33. Touw-Otten F. W., Johansen K. S. Diagnosis, antibiotic treatment and outcome of acute tonsillitis: report of a WHO Regional Office for Europe study in 17 European countries. Fam Pract. 1992 Sep;9(3):255–262. doi: 10.1093/fampra/9.3.255. [DOI] [PubMed] [Google Scholar]
  34. Valkenburg H. A., Haverkorn M. J., Goslings W. R., Lorrier J. C., De Moor C. E., Maxted W. R. Streptococcal pharyngitis in the general population. II. The attack rate of rheumatic fever and acute glomerulonephritis in patients. J Infect Dis. 1971 Oct;124(4):348–358. doi: 10.1093/infdis/124.4.348. [DOI] [PubMed] [Google Scholar]
  35. Veasy L. G., Tani L. Y., Hill H. R. Persistence of acute rheumatic fever in the intermountain area of the United States. J Pediatr. 1994 Jan;124(1):9–16. doi: 10.1016/s0022-3476(94)70247-0. [DOI] [PubMed] [Google Scholar]
  36. Wallace M. R., Garst P. D., Papadimos T. J., Oldfield E. C., 3rd The return of acute rheumatic fever in young adults. JAMA. 1989 Nov 10;262(18):2557–2561. [PubMed] [Google Scholar]
  37. Walsh B. T., Bookheim W. W., Johnson R. C., Tompkins R. K. Recognition of streptococcal pharyngitis in adults. Arch Intern Med. 1975 Nov;135(11):1493–1497. [PubMed] [Google Scholar]
  38. Wasson J. H., Sox H. C. Clinical prediction rules. Have they come of age? JAMA. 1996 Feb 28;275(8):641–642. doi: 10.1001/jama.275.8.641. [DOI] [PubMed] [Google Scholar]
  39. el-Daher N. T., Hijazi S. S., Rawashdeh N. M., al-Khalil I. A., Abu-Ektaish F. M., Abdel-Latif D. I. Immediate vs. delayed treatment of group A beta-hemolytic streptococcal pharyngitis with penicillin V. Pediatr Infect Dis J. 1991 Feb;10(2):126–130. doi: 10.1097/00006454-199102000-00010. [DOI] [PubMed] [Google Scholar]

Articles from CMAJ: Canadian Medical Association Journal are provided here courtesy of Canadian Medical Association

RESOURCES