[Skip to Navigation]
Sign In
July 1999

Management of Sore Throats in Children: A Cost-effectiveness Analysis

Author Affiliations

From the Section of Outcomes Research, Division of General Internal Medicine, Department of Internal Medicine (Dr Tsevat), Divisions of Neonatology and Health Policy and Clinical Effectiveness, Department of Pediatrics (Dr Kotagal), and Institute for Health Policy and Health Services Research (Drs Tsevat and Kotagal), University of Cincinnati Medical Center and Children's Hospital Medical Center, Cincinnati, Ohio.

Arch Pediatr Adolesc Med. 1999;153(7):681-688. doi:10.1001/archpedi.153.7.681

Objective  To perform a cost-effectiveness analysis of treatment management strategies for children older than 3 years who present with signs or symptoms of pharyngitis.

Design  Decision model with 7 strategies, including neither testing for streptococcus nor treating with antibiotics; treating empirically with penicillin V; basing treatment on results of a throat culture (Culture); and basing treatment on results of enzyme immunoassay or optical immunoassay rapid tests, performed alone or in combination with throat cultures. In these 7 strategies, all tests are performed in a local reference laboratory. In a sensitivity analysis, we examined the cost-effectiveness of 4 strategies involving office-based testing. We obtained data on event probabilities and test characteristics from our hospital's clinical laboratory and the literature; costs for the analysis were based on resource use.

Results  At a baseline prevalence of 20.8% for streptococcal pharyngitis, the Culture strategy was the least expensive and most effective, with an average cost of $6.85 per patient. The outcome was sensitive to the prevalence of streptococcal pharyngitis, the rheumatic fever attack rate, the cost of the enzyme immunoassay test, and the cost of culturing and reporting culture results. The Culture strategy was also preferred if amoxicillin was substituted for oral penicillin. For office-based testing, Culture was the least costly strategy, but treatment based on results of the optical immunoassay test alone had an incremental cost-effectiveness ratio of $1.6 million per additional life saved.

Conclusion  In a setting with adherent patients, children with sore throats should generally get throat cultures in lieu of rapid streptococcus antigen tests.

SORE THROATS are one of the most common presenting complaints of patients, accounting for nearly 18 million office visits in 1996.1 Although the one to cause the most concern, group A β-hemolytic streptococcus (GABHS) is only one of many causes of sore throats, accounting for 15% to 30% of cases in recent reviews,2-4 with significant geographic, seasonal, and age variation, especially in children.5 When streptococcal pharyngitis is present, it is important to treat the patient with antibiotics to prevent acute rheumatic fever (ARF) in the host, prevent transmission, and perhaps decrease the duration of symptoms and prevent suppurative complications. Penicillin therapy—despite being the therapy of choice6—carries the risk of adverse reaction, including anaphylaxis, financial cost, and the potential of contributing to the emergence of resistant strains, so penicillin should not be prescribed indiscriminately.

Although there is general agreement that patients with streptococcal pharyngitis should receive antibiotic treatment, there continues to be wide variation in other facets of management.7-10 Regarding testing for streptococcus, there is now a choice among several types of rapid antigen tests11 with or without the standard throat culture, there is variation in culture technique regarding the type of atmosphere and identification method,12 and there is a choice between performing the test in the physician's office or a laboratory.4

There is also practice variation in the way tests are used to guide therapy.7 According to the threshold model of clinical decision making,13 testing and treatment decisions should be based on the probability of disease (here streptococcal pharyngitis) and the risks and benefits as sociated with testing and treatment. Several predictive models based on clinical findings are available to aid clinicians in assessing the probability that the patient has streptococcal pharyngitis.14-27 Nevertheless, as Poses and coworkers28 found, educational intervention decreases overestimation of the probability of streptococcal infection but does not change prescribing habits or practice variation.

Several analysts18,29-35 have gone a step beyond developing predictive instruments by performing decision analyses and/or economic analyses of the management of sore throats. However, most of the previous analyses used data from adults and are not necessarily applicable to children, particularly in the office setting. Most were done before the advent of the rapid test, and none included the optical immunoassay (OIA) rapid test.36-38 The cost data for the economic analyses were either old—from the 1970s—or incomplete. To reexamine the issue of how best to manage the treatment of children with sore throats in an office setting, we performed a cost-effectiveness analysis. The analysis applies to children older than 3 years who present with signs or symptoms of pharyngitis and who can be expected to adhere to the physician's management plan.


The decision model

We constructed a decision analysis model to examine the short-term costs and cost-effectiveness associated with 7 strategies:

  • Neither test nor treat (Do Nothing).

  • Perform an enzyme immunoassay (EIA) rapid test. If results are positive, prescribe penicillin V—250 mg orally thrice daily for 10 days; if results are negative, do nothing (EIA Only).

  • Perform an EIA rapid test. If results are negative, obtain a culture; if findings of either test are positive, prescribe penicillin (EIA/Culture).

  • Perform an OIA rapid test. If results are positive, prescribe penicillin; if results are negative, do nothing (OIA Only).

  • Perform an OIA rapid test. If results are negative, obtain a culture; if findings of either test are positive, prescribe penicillin (OIA/Culture).

  • Obtain a culture. If results are positive, prescribe penicillin (Culture).

  • Treat empirically (Empiric Therapy).

In our base case analysis, all tests are performed in a local reference laboratory. A recent report by Gerber and colleagues38 examined the accuracy of office-based testing and found that office-based OIA tests were more sensitive but less specific than office-based cultures. Based on these findings, the authors concluded that negative OIA test results may not always need to be confirmed with throat cultures. Thus, in a sensitivity analysis, we compared the expected cost and cost-effectiveness of 4 office-based strategies: Do Nothing, Empiric Therapy, OIA Only, and Culture.

In all models, patients with untreated streptococcal infection risk developing ARF, which could involve complications or be fatal, and suppurative complications. Treating the patient with penicillin reduces the risk of developing ARF and suppurative complications. However, with penicillin therapy, the patient risks developing a rash or anaphylaxis or both; anaphylaxis can be fatal. Patients sustaining a nonfatal reaction to penicillin are switched to erythromycin therapy per recently published guidelines.6 All analyses were performed using a decision analysis software program (Decision Maker version 7.0; Pratt Medical Group, Boston, Mass).


For the analyses, we made several simplifying assumptions. Because serum titers for streptococcal pharyngitis are rarely performed, the diagnosis of "definite" streptococcal pharyngitis is rarely confirmed. Therefore, performing the laboratory culture is generally regarded as the criterion standard—imperfect sensitivity and specificity notwithstanding.12,39 Thus, in the base case analysis, we assumed the local reference laboratory throat culture (as opposed to the office-based culture) to be the criterion standard.

We further assumed that the effectiveness of penicillin therapy in reducing the risk of rheumatic fever and suppurative complications is not diminished by a 2-day delay in treatment.6 Next, in accordance with recent studies,40,41 we assumed that penicillin therapy has no benefit with regard to the duration of illness (this assumption could bias the analysis in favor of Do Nothing and any imperfect testing strategies).

We also made several assumptions regarding costs. First, per common practice in many physician's offices, we assumed that nurses, rather than physicians, would notify the patient of throat culture results, instruct the patient to take or forgo antibiotics, and call in prescriptions to the pharmacy as appropriate. Second, we did not consider the costs of transporting specimens—for the base case analysis, this simplification biases against the Do Nothing and Empiric Therapy strategies; for the office-based testing sensitivity analysis, such costs are not pertinent. Even when rapid tests were sent to the reference laboratory, we assumed the results would be available before the patient left the physician's office, eliminating notification costs; this assumption favors the rapid test strategies. Because we used a short time frame for the analysis, costs of secondary rheumatic fever prophylaxis were not considered (although such costs would be discounted, this assumption biases the analysis against the Empiric Therapy and Culture strategies).

Finally, in accordance with recent recommendations by an expert panel,42 the base case analysis takes the societal perspective (excluding contagion) and does not consider costs such as the patient's parent missing work and the patient's loss of future productivity because of death or the development of long-term complications from rheumatic fever.

In a sensitivity analysis, we ascertained the cost-effectiveness of the 7 strategies from the perspective of a parent, including time costs for missing work. Here, we assumed a patient with streptococcal pharyngitis would require 24 hours of antibiotic therapy before returning to day care or school43 and that a patient with undiagnosed streptococcal pharyngitis would miss day care or school for 1 day because of illness. We further assumed patients whose rapid test results were negative but whose culture results were positive would miss 2 days of day care or school. With the Culture strategy, all patients were assumed to miss 2 days of day care or school—those with positive culture results would start treatment 1 day later than patients with positive rapid test results, and those with negative culture results would stay home until notified of the results. Note that this parental perspective analysis assumes the parent is employed full-time and the child becomes ill during the work week. Thus, to the extent that the time costs represent an upper bound estimate, the analysis would be biased against the Culture strategy.

Probabilities and costs


We used the following probability estimates in our model, all of which were varied in sensitivity analyses to see whether changes in estimates affected the outcome (Table 1).

Table 1. 
Input Data for GABHS Cost-effectiveness Analysis*
Input Data for GABHS Cost-effectiveness Analysis*

Prevalence of GABHS Infection

The prevalence of GABHS pharyngitis, defined as the proportion of throat cultures that grow GABHS, ranges from 15% to 30% in the literature.2-4 At our children's hospital, routine practice is to obtain throat swabs from every patient with pharyngitis, and the prevalence of GABHS is 20.8% (S. Reising, PhD, oral communication, January 1996), which is the estimate used in our model.

Test Characteristics of the EIA Rapid Test

At our children's hospital, the sensitivity of the EIA rapid test is 85.9% (S. Reising, PhD, oral communication, January 1996) and is comparable to previous studies in children.11,12,44,45 The specificity of the EIA rapid test at our hospital is 94.3% and is similar to or perhaps slightly lower than the specificity reported elsewhere.11,12,44,45 We used local estimates in the base case analysis but varied the estimates widely in sensitivity analyses.

Test Characteristics of the OIA Rapid Test

We used the test characteristics of the OIA rapid test as reported at our children's hospital, where the sensitivity is 80.8% and the specificity is 89.5% (S. Reising, PhD, oral communication, January 1996). These values are less favorable than the manufacturer's data (sensitivity of 98.9% and specificity of 98.4%) (K. DiSilvestro, written communication, August 1995) or those from previous studies36,37; thus, the values were varied in sensitivity analyses. For the office-based testing analysis, we used a sensitivity of 84% and a specificity of 93%, with a culture sensitivity of 78% and culture specificity of 99%, as reported by Gerber et al.38

Penicillin Reaction

The risk of the patient developing an allergic reaction to penicillin is 0.7% to 4.0%.46-48 We set the probability of the patient developing a drug allergy from penicillin therapy at 1.5%. We set the risk of the patient developing an anaphylactic penicillin reaction at 1 per 10,000 and the case-fatality rate from such a reaction at 10%.46-49

Probability of ARF Following Untreated Streptococcal Pharyngitis

The probability of the patient developing ARF from untreated streptococcal pharyngitis depends primarily on whether there is an ongoing epidemic. In epidemic times, the risk of developing ARF can be as high as 3%50,51; in endemic times, the risk is probably considerably lower,5,18,31,52 although a leading textbook of pediatrics disagrees.53 For the base case analysis, we used a conservatively high estimate of 3% and varied the probability widely in a sensitivity analysis.

Morbidity and Mortality From ARF

For the morbidity and mortality from ARF, we used published estimates by Hillner and Centor31: 1% of cases are fatal and 10% result in nonfatal complications.

Effectiveness of Penicillin Therapy in Preventing ARF

Del Mar41 summarized the controlled trials of penicillin therapy in preventing ARF and found that penicillin therapy reduced the risk of developing ARF by 75%. We used Del Mar's estimate as our baseline and varied the estimate in a sensitivity analysis.

Suppurative Complications Following Streptococcal Pharyngitis

Untreated streptococcal infection can result in peritonsillar or retropharyngeal abscesses, otitis media, sinusitis, and cervical adenitis; it can also result in life-threatening infections such as necrotizing fasciitis, malignant scarlet fever, bacteremia, and streptococcal toxic shock syndrome.54-56 The risk of the patient developing one of the life-threatening infections is difficult to quantify,54 whereas the risk of the patient developing peritonsillar abscess is 1% to 2%.31-33 For this analysis, we focused on peritonsillar and retropharyngeal abscesses and used a risk of 1.25%, the average of 2 published estimates.32,33

Effectiveness of Penicillin Therapy in Preventing Suppurative Complications

Del Mar's review revealed only one study evaluating the effectiveness of penicillin in preventing peritonsillar abscess, in which the risk was reduced by 89%.41,57 We used 89% as our baseline estimate.


Cost estimates in this analysis represent actual resource costs rather than charges58 ( Table 1). All costs were converted to 1995 US dollars using the medical care component of the consumer price index. Because of the short time frame for the analysis, we did not discount costs. As with probability estimates, we subjected all cost estimates to sensitivity analysis to see how changes in baseline values affected the results.


Costs of performing the EIA rapid test, the OIA rapid test, and the throat culture were obtained from internal data at Biostar (K. DiSilvestro, written communication, August 1995). The cost of the EIA rapid test, including the test itself and the requisite quality control, is $3.90. The analogous cost of the OIA rapid test is $6.50. The cost of pharyngeal culture, including materials, quality control, and labor, is $2.40.

Notifying Patients of Culture Results, Calling in Prescriptions

Because culture results take 2 days to be completed, we incorporated the cost of calling patients with notification of the results and instructions on whether to get penicillin at the pharmacy. We surveyed 2 pediatrician's offices and found that it takes an average of 212 minutes for an office nurse to reach a patient and report the results. The estimated salary for an office nurse is $12 to $15 per hour (J. Weiland, RN, oral communication, March 1996). Using a salary of $15 per hour, the cost of notifying the patient is $0.63.

We also determined the time it takes an office nurse to call in a prescription to the pharmacy by timing calls to 155 patients. The mean time was 1.7 minutes, giving an estimated prescription call-in cost of $0.43.

Penicillin Therapy

The cost of penicillin therapy is based on a dose of 250 mg taken orally 3 times daily for 10 days.6 The wholesale cost of penicillin V elixir at that dose is $3.78,59 to which we added a pharmacy dispensing cost of $5.28,60 for a total cost of $9.06.

Amoxicillin Therapy

Although penicillin is the recommended agent of choice, many pediatricians prescribe amoxicillin instead.4 We did a sensitivity analysis that looked at using amoxicillin—250 mg orally 3 times a day for 10 days. The total for the acquisition and dispensing cost is $8.22.59,60

Penicillin Rash

In our analysis, treating a drug rash incurs the following costs:

  • $1.25 in nursing time (5 minutes at $15 per hour, based on a survey of 3 pediatrician's offices);

  • $24 in physician time (based on the resource-based relative value scale reimbursement rate in Ohio for Physicians' Current Procedural Terminology [CPT] code 9921261) for an office visit;

  • $5.52 for a 2-day course of diphenhydramine—12.5 mg orally 4 times daily (wholesale acquisition plus dispensing cost)59,60; and

  • $19.22 for a 10-day course of erythromycin ethylsuccinate—200 mg orally 4 times daily6 (wholesale acquisition plus dispensing cost).59,60


Based on a previous analysis, the cost of treating anaphylaxis was estimated to be $1500.49

Acute Rheumatic Fever

The cost of ARF was first estimated by Tompkins and colleagues29 in a cost-minimization analysis published in 1977. Adjusting that cost to 1995 dollars, the cost would be $40,842 per case. That estimate, however, is probably far too high for this analysis because most cases of ARF are now treated on an outpatient basis and because that estimate includes the cost of premature death (not included in this analysis). A study62 conducted in New Zealand found that the cost of treating uncomplicated ARF was US $13,650 and the cost of treating a complicated case was US $45,536. Because cost data from the 1970s or from New Zealand are likely not generalizable to current US costs, we obtained financial data from our hospital's financial accounting department for 34 consecutive cases of ARF (including 7 inpatients) seen in fiscal years 1994-1996.

The cost accounting system (HBOC, Atlanta, Ga) estimates all of the relevant costs except for physician fees. We estimated physician fees using resource-based relative value scale inpatient and outpatient reimbursement rates, as follows:

  • For inpatients, we assigned an admission day cost of $97.83 (CPT code 99222), then $46.22 for each subsequent day (CPT code 99232), and then $52.00 for discharge day management (CPT code 99238). We also added $123.95 and $25.22 for a consultation (CPT codes 99254 and 99261, respectively).

  • For outpatients, we added $87.16 for new patient visits (CPT code 99204) and $24 for established patient visits (CPT code 99212).

Including estimated physician costs, the mean variable cost per patient with ARF, rounded to the nearest $100, was $700. We used that estimate for our base case cost but examined costs as high as $20,000 in a sensitivity analysis.

Suppurative Complications

Costs for treating patients with peritonsillar or retropharyngeal abscess (n=117) were estimated in a similar fashion—by adding any hospitalization costs to physician costs. Physician costs were estimated in the same way as estimated for ARF, except that new outpatients were assigned a lower cost of $43.17, representing a less complex CPT visit code (99202), and no inpatient consultation fees were added because most inpatients were hospitalized on the otolaryngology service. The mean variable cost for suppurative complications, including estimated physician fees, was $2000.

Costs From the Parent's Perspective

For the analysis of costs from the parent's perspective, we assumed a co-payment of $5 for office visits and $3 for prescriptions. For a working parent, the major germane costs are the time costs associated with missing work to care for the ill child (see "Assumptions" subsection of "Methods" section). We valued the time cost at $11.43 per hour, based on data from the Bureau of Labor Statistics.63 For children who developed a rash, we estimated that the parent would miss half a day of work to take the child to the physician. Finally, we estimated that children with anaphylactic reactions would miss 2 days of day care or school and that children with ARF or suppurative complications would miss 5 days of day care or school.


Base case analysis

Under baseline assumptions, probabilities, and cost estimates, the Culture strategy has the lowest average cost per patient ( Table 2). The Culture strategy is followed by EIA Only, Do Nothing, EIA/Culture, and Empiric Therapy. The OIA Only and OIA/Culture strategies are the most expensive. Culture also saves the greatest number of lives; by being less costly and more effective than the other 6 strategies, it is considered dominant from a cost-effectiveness standpoint.

Table 2. 
Cost-effectiveness of Pharyngitis Management Strategies*
Cost-effectiveness of Pharyngitis Management Strategies*

Sensitivity analyses (laboratory-based testing)

Prevalence of GABHS Infection

In the base case analysis, the estimated prevalence of GABHS infection was 20.8%. From a cost-minimization standpoint, if the prevalence is less than 11%, the Do Nothing strategy is the least expensive. If the prevalence is greater than 66.8%, the physician should prescribe penicillin without testing. From a cost-effectiveness standpoint, for any prevalence between 11% and 66.8%, Culture is the dominant strategy.

ARF Attack Rate

In the base case analysis, we assumed the risk of developing ARF in untreated patients with streptococcal pharyngitis to be 3%. If the prevalence is less than 0.51%, the Do Nothing strategy is the least expensive. At a prevalence of 0.3%, one tenth of our baseline risk estimate, the incremental cost-effectiveness of Culture relative to Do Nothing is $88,246 per additional life saved. At a prevalence of 0.03%, one one-hundreth of our baseline risk estimate, Do Nothing is the dominant strategy.

Risk of Suppurative Complications

In the base case analysis, the risk of developing a suppurative complication from untreated streptococcal pharyngitis was 1.25%. If the actual risk were less than 0.52%, the Do Nothing strategy would be the least expensive, but the Culture strategy would be the most effective.

Cost of Culture

In the base case analysis, the cost of obtaining a throat culture was estimated to be $2.40. At a cost of culture greater than $4.46, the EIA Only strategy would be the least expensive, but the Culture strategy would be the most effective.

Cost of Follow-up

We estimated the cost of reporting culture results to patients to be $0.63. If the cost is greater than $2.68, then EIA Only would be the least expensive strategy and Culture would be the most effective. If the cost of calling in a prescription exceeds $10.32 (baseline estimate=$0.43), then the EIA Only strategy would be the least expensive, with Culture remaining the most effective.

Cost of the EIA Rapid Test

In the baseline estimate, the cost of the EIA rapid test was $3.90. If the cost is less than $1.84, EIA Only would be the least expensive strategy and Culture would be the most effective.

Cost of the OIA Rapid Test

In the baseline estimate, the cost of performing an OIA test was $6.50. The cost would have to be less than $1.17 for the OIA Only strategy to be the least expensive.

Cost of Treating ARF

In the base case analysis, the cost of treating ARF was estimated at $700 per patient. At any cost greater than $119, Culture is the dominant strategy.

Cost of Treating Suppurative Complications

At costs of treating suppurative complications below $825 per patient (baseline cost=$2000), the Do Nothing strategy is the least expensive, and Culture is the most effective.

Amoxicillin Rather Than Penicillin

If amoxicillin is used for treatment instead of penicillin, Culture is the least expensive strategy as long as the prevalence of GABHS infection is 10.6% to 63.9%. At the baseline prevalence of GABHS infection (20.8%), Culture dominates even if the probability of developing a rash from amoxicillin therapy is 10%.

For laboratory-based testing, the outcome was not sensitive to wide changes in each of the following variables: sensitivity of the EIA rapid test, specificity of the EIA rapid test, sensitivity of the OIA rapid test, specificity of the OIA rapid test, risk of adverse reaction to penicillin (rash or anaphylaxis), risk of complications from ARF, mortality from ARF, and effectiveness of penicillin therapy in preventing ARF and suppurative complications. The outcome was also not sensitive to the cost of penicillin, diphenhydramine, and erythromycin therapy, and to the cost of penicillin reactions.

Office-Based Testing

Among the 4 office-based strategies, Culture is the least expensive at $8.20 per patient, followed by Do Nothing ($9.57), Empiric Therapy ($11.62), and OIA Only ($11.72). Because of imperfect sensitivity and specificity, office-based culturing is not the most effective strategy in terms of lives saved. The incremental cost-effectiveness of OIA Only relative to Culture is $1.6 million per additional life saved.

Parent's Perspective

From a parent's perspective, the 2 least expensive strategies are Do Nothing ($23.13) and Empiric Therapy ($23.75). The 2 EIA strategies are several dollars more expensive, followed by the 2 OIA strategies, which are Dominated. The most expensive strategy is Culture ($184.54), owing to 2 days of missed work.


By nature of its high incidence, pharyngitis is a major health and economic issue, yet there is no agreement on how to care for children with sore throats. Despite the advent of new diagnostic tests with reasonably good sensitivities and specificities and short turn-around times, our analysis suggests that, in an office setting with adherent patients and with tests performed in a local reference laboratory, from the societal perspective, antibiotic therapy guided by the traditional throat culture is the least costly and most effective strategy. When tests are performed in an office laboratory, culturing is the least expensive strategy, with OIA testing marginally more effective. Given children's long life expectancies, at an incremental cost-effectiveness ratio of $1.6 million per additional life saved, office-based OIA testing is an economically reasonable alternative to office-based culturing. By comparison, screening newborns for sickle cell disease costs $3100 to $450 billion (in 1987 dollars) more per life saved than not screening, depending on the population screened.49

Several other decision and economic analyses of caring for patients with pharyngitis have been reported.18,29-35 Two analyses pertained specifically to children. Dippel and coworkers33 published a decision analysis for teenagers with acute pharyngitis. They considered 5 strategies: (1) symptomatic treatment only; (2) empiric therapy with penicillin; (3) testing with a rapid agglutination test; (4) culturing and awaiting culture results before treating; and (5) culturing and initiating treatment while awaiting culture results, then discontinuing therapy if results are negative. Outcomes were expressed as quality-adjusted days of life lost. Testing with a rapid agglutination test was favored, but only by a matter of a few quality-adjusted minutes. In essence, the decision was a toss-up. Economic costs were not considered.

Lieu et al32 performed a cost-effectiveness analysis of the management of pharyngitis in children seen in an emergency department. They considered 4 strategies: (1) culture; (2) perform a rapid test (latex agglutination) only (Rapid Test Only); (3) perform a rapid test; if results are negative, culture (Rapid Test/Culture); and (4) treat empirically. Differences from most previous models were the addition of a Rapid Test/Culture strategy, an assumed high loss to follow-up rate (43% of patients with positive culture results were assumed to go untreated), and less than perfect sensitivity of culture and effectiveness of treatment in preventing ARF. Results showed that the Culture strategy yielded the fewest penicillin reactions per case of ARF prevented. The Treat Empirically strategy had the lowest cost per disease or complication prevented. The Rapid Test Only strategy had the lowest cost per patient ($0.06 lower than Treat Empirically). The incremental cost-effectiveness of Rapid Test/Culture vs Culture was $6475 per additional case of rheumatic fever prevented or $3885 per additional case of suppurative complications prevented. Their recommendation was to perform the rapid test followed by a culture if the test results were negative.

Unlike the analysis of Lieu and coworkers,32 which pertained to inner-city emergency department populations with a high loss to follow-up rate, the current analysis pertains to an office population with complete follow-up64 and includes the OIA rapid test. In our base case analysis, the Empiric Therapy strategy was preferred to at least 2 of the rapid test strategies in nearly all circumstances. Thus, one can infer from the analysis that if loss to follow-up is a concern, Empiric Therapy—perhaps with penicillin G benzathine given intramuscularly—could be the preferred strategy overall.65,66 This argument is bolstered when one realizes that although the turnaround time for the rapid tests is short, it may take much longer to get results if transportation time to the laboratory is an issue. Under these circumstances, a patient may not be able to wait in the physician's office for results, and the advantage of the rapid test is lost (there would be an added notification cost as well). Under one scenario in which there is no notification cost for the rapid test and the notification cost for reporting culture results is several times higher than our baseline estimate—as may be the case if a physician calls the patient or if the patient is hard to reach—the EIA Only strategy is the least expensive.

The previous decision and economic analyses have several limitations. Most were conducted before the advent of the rapid test, and none included the OIA rapid test. The cost data for the economic analyses are either old, are based on very few patients, pertain to adults, or reflect charges rather than costs.58

The current analysis also has certain limitations. First, the analysis assumes that patients would adhere to the physician's management plan. In such settings, Pantell and Berwick67 also advocate Culture over other strategies.

Second, we did not include the costs of long-term complications and of secondary antibiotic prophylaxis for patients with rheumatic fever. Such costs, if included, would have to be discounted to present value, mitigating their impact. Even so, excluding those costs biases the analysis against the Culture and Empiric Therapy strategies, the 2 strategies most likely to avoid such costs. But while the cost of rheumatic fever may have been underestimated, any underestimate would likely be offset by our ARF attack rate, which represents an upper bound of many published estimates. Furthermore, our sensitivity analyses show that Culture is the dominant strategy at essentially any cost of rheumatic fever and is relatively cost-effective even at much lower attack rates.

Third, the analyses favoring Culture did not model time costs. The issue of time costs highlights the need to keep in mind the perspective of the analysis. From a parent's perspective, the rapid streptococcal tests provide timely information that may enable the child to return to day care or school 1 or 2 days sooner than if they had to await a culture result. However, the rapid test results are sometimes erroneous. For example, using the baseline prevalence of GABHS of 20.8%, OIA sensitivity of 80.8%, and OIA specificity of 89.5%, the negative predictive value of the OIA rapid test is 94.7%. This means that 5.3% of children with negative results from an OIA rapid test actually have streptococcal pharyngitis and might be sent back to day care or school before receiving treatment, thereby exposing other children, which is an adverse outcome from the societal perspective. Also, there is concern that if a physician treats streptococcal pharyngitis too early in its course (before an antibody response can be mounted), the risk of relapse increases.4,68,69 Our analysis incorporated neither a benefit nor a penalty for early therapy per se (any benefit of early therapy would favor the Empiric Therapy strategy, particularly from the parent's perspective).

Our analysis did not examine antibiotic regimens other than penicillin, amoxicillin, and erythromycin for patients allergic to penicillin.70 Although shorter courses of some of the newer agents have been tried, a recent expert panel71 did not endorse them. Finally, we did not consider a strategy of caring for patients over the telephone exclusively. In other words, this analysis assumed that all children with sore throats would be seen at least once in the physician's office. Without such a requirement, Empiric Therapy would be the least costly strategy, but it is not clear that such a strategy would be acceptable to pediatricians or family physicians; furthermore, indiscriminate use of antibiotics could hasten the advent of resistant strains, greatly complicating and compromising the care of future patients.

In practice, the treatment of patients with sore throats is often driven by the wishes of the patient72 (in this analysis, the parent). A parent may pressure the physician into performing a rapid streptococcal test to "know" whether the child has streptococcal pharyngitis so that if the test results are negative, the parent could send the patient back to day care or school a day earlier. But Froehlich and Welch73 recently demonstrated that physicians can reduce unnecessary testing without compromising patient satisfaction.

We conclude that, in most cases, a physician should obtain a throat culture from adherent children with sore throats.

Accepted for publication October 15, 1998.

This study was funded in part by ChoiceCare, Cincinnati, Ohio, a managed care organization.

Presented at the 18th Annual Meeting of the Society for Medical Decision Making, Toronto, Ontario, October 16, 1996.

We gratefully acknowledge Elisa Immerman; Eileen Moore, MD; Jay Moskovitz; Jeanne Weiland; Rose Allgaier; Cindy DiLandro; Tara Baker and the many nurses and medical assistants from Northeast Cincinnati Pediatric Associates and Pediatric Associates of Mt Carmel, Cincinnati, who helped obtain the cost data; Bennett Lee, MD, and Karen Mandell, PharmD, for data entry; and Frank Sonnenberg, MD, for helpful suggestions regarding the decision model.

Corresponding author: Joel Tsevat, MD, MPH, Section of Outcomes Research, Division of General Internal Medicine, University of Cincinnati Medical Center, 231 Bethesda Ave, Cincinnati, OH 45267-0535 (e-mail: joel.tsevat@uc.edu).

Woodwell  DA National Ambulatory Medical Care Survey: 1996 Summary.  Hyattsville, Md National Center for Health Statistics1997;Advance Data From Vital and Health Statistics, No. 295.
Bonilla  JABluestone  CD Pharyngitis: when is aggressive treatment warranted?  Postgrad Med. 1995;9761- 69Google Scholar
Bisno  AL Acute pharyngitis: etiology and diagnosis.  Pediatrics. 1996;97(suppl)949- 954Google Scholar
Pichichero  ME Group A streptococcal tonsillopharyngitis: cost-effective diagnosis and treatment.  Ann Emerg Med. 1995;25390- 403Google ScholarCrossref
Holmberg  SDFaich  GA Streptococcal pharyngitis and acute rheumatic fever in Rhode Island.  JAMA. 1983;2502307- 2312Google ScholarCrossref
Dajani  ATaubert  KFerrieri  PPeter  GShulman  SCommittee on Rheumatic Fever, Endocarditis, and Kawasaki Disease of the Council on Cardiovascular Disease in the Young, American Heart Association, Treatment of acute streptococcal pharyngitis and prevention of rheumatic fever: a statement for health professionals.  Pediatrics. 1995;96758- 764Google Scholar
Cochi  SLFraser  DWHightower  AWFacklam  RRBroome  CV Diagnosis and treatment of streptococcal pharyngitis: survey of US medical practitioners. Shulman  STed. Pharyngitis—Management in an Era of Declining Rheumatic Fever. New York, NY Praeger Press1984;73- 94Google Scholar
Schwartz  BFries  SFitzgibbon  AMLipman  H Pediatricians' diagnostic approach to pharyngitis and impact of CLIA 1988 on office diagnostic tests.  JAMA. 1994;271234- 238Google ScholarCrossref
Bisno  ALCollaborative Streptococcal Study Group, Microbial diagnosis of streptococcal pharyngitis: results of a national survey.  Paper presented at: 33rd Interscience Conference on Antimicrobial Agents and Chemotherapy October 17-20, 1993 New Orleans, LaAbstract 1557.
Poses  RMWigton  RSCebul  RDCentor  RMCollins  MFleischli  GJ Practice variation in the management of pharyngitis: the importance of variability in patients' clinical characteristics and in physicians' responses to them.  Med Decis Making. 1993;13293- 301Google ScholarCrossref
Facklam  RR Specificity study of kits for detection of group A streptococci directly from throat swabs.  J Clin Microbiol. 1987;25504- 508Google Scholar
Gerber  MA Comparison of throat cultures and rapid strep tests for diagnosis of streptococcal pharyngitis.  Pediatr Infect Dis J. 1989;8820- 824Google ScholarCrossref
Pauker  SGKassirer  JP The threshold approach to clinical decision making.  N Engl J Med. 1980;3021109- 1117Google ScholarCrossref
Breese  BBDisney  FA The accuracy of diagnosis of β-hemolytic streptococcal infections on clinical grounds.  J Pediatr. 1954;44670- 673Google ScholarCrossref
Stillerman  MBernstein  SH Streptococcal pharyngitis: evaluation of clinical syndromes in diagnosis.  AJDC. 1961;101476- 489Google Scholar
Honikman  LHMassell  BF Guidelines for the selective use of throat cultures in the diagnosis of streptococcal respiratory infection.  Pediatrics. 1971;48573- 582Google Scholar
Kaplan  ELTop  FH  JrDudding  BAWannamaker  LW Diagnosis of streptococcal pharyngitis: differentiation of active infection from the carrier state in the symptomatic child.  J Infect Dis. 1971;123490- 501Google ScholarCrossref
Forsyth  RA Selective utilization of clinical diagnosis in treatment of pharyngitis.  J Fam Pract. 1975;2173- 177Google Scholar
Walsh  BTBookheim  WWJohnson  RCTompkins  RK Recognition of streptococcal pharyngitis in adults.  Arch Intern Med. 1975;1351493- 1497Google ScholarCrossref
Breese  BB A simple scorecard for the tentative diagnosis of streptococcal pharyngitis.  AJDC. 1977;131514- 517Google Scholar
Wood  RWTompkins  RKWolcott  BW An efficient strategy for managing acute respiratory illness in adults.  Ann Intern Med. 1980;93757- 763Google ScholarCrossref
Centor  RMWitherspoon  JMDalton  HPBrody  CELink  K The diagnosis of strep throat in adults in the emergency room.  Med Decis Making. 1981;1239- 246Google ScholarCrossref
Komaroff  ALPass  TMAronson  MD  et al.  The prediction of streptococcal pharyngitis in adults.  J Gen Intern Med. 1986;11- 7Google ScholarCrossref
Reed  BDHuck  WFrench  T Diagnosis of group A β-hemolytic streptococcus using clinical scoring criteria, Directigen 1-2-3 group A streptococcal test, and culture.  Arch Intern Med. 1990;1501727- 1732Google ScholarCrossref
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;10295- 300Google ScholarCrossref
Meland  EDigranes  ASkjaerven  R Assessment of clinical features predicting streptococcal pharyngitis.  Scand J Infect Dis. 1993;25177- 183Google ScholarCrossref
McIsaac  WJWhite  DTannenbaum  DLow  DE A clinical score to reduce unnecessary antibiotic use in patients with sore throat.  CMAJ. 1998;15875- 83Google Scholar
Poses  RMCebul  RDWigton  RS You can lead a horse to water: improving physicians' knowledge of probabilities may not affect their decisions.  Med Decis Making. 1995;1565- 75Google ScholarCrossref
Tompkins  RKBurnes  DCCable  WE An analysis of the cost-effectiveness of pharyngitis management and acute rheumatic fever prevention.  Ann Intern Med. 1977;86481- 492Google ScholarCrossref
Cebul  RDPoses  RM The comparative cost-effectiveness of statistical decision rules and experienced physicians in pharyngitis management.  JAMA. 1986;2563353- 3357Google ScholarCrossref
Hillner  BECentor  RM What a difference a day makes: a decision analysis of adult streptococcal pharyngitis.  J Gen Intern Med. 1987;2242- 248Google ScholarCrossref
Lieu  TAFleisher  GRSchwartz  JS Cost-effectiveness of rapid latex agglutination testing and throat culture for streptococcal pharyngitis.  Pediatrics. 1990;85246- 256Google Scholar
Dippel  DWTouw-Otten  FHabbema  JDF Management of children with acute pharyngitis: a decision analysis.  J Fam Pract. 1992;34149- 159Google Scholar
Smith  DLBrauer  WA Comparative costs of diagnosis and treatment in acute pharyngitis.  South Med J. 1981;74332- 334Google ScholarCrossref
Hedges  JRLowe  RA Streptococcal pharyngitis in the emergency department: analysis of therapeutic strategies.  Am J Emerg Med. 1986;4107- 115Google ScholarCrossref
Daly  JAKorgenski  EKMunson  ACLlausus-Magana  E Optical immunoassay for streptococcal pharyngitis: evaluation of accuracy with routine and mucoid strains associated with acute rheumatic fever outbreak in the intermountain area of the United States.  J Clin Microbiol. 1994;32531- 532Google Scholar
Della-Latta  PWhittier  SHosmer  MAgre  F Rapid detection of group A streptococcal pharyngitis in a pediatric population with optical immunoassay.  Pediatr Infect Dis J. 1994;13742- 743Google ScholarCrossref
Gerber  MATanz  RRKabat  W  et al.  Optical immunoassay test for group A β-hemolytic streptococcal pharyngitis: an office-based, multicenter investigation.  JAMA. 1997;277899- 903Google ScholarCrossref
Centor  RMMeier  FADalton  HP Throat cultures and rapid tests for diagnosis of group A streptococcal pharyngitis.  Ann Intern Med. 1986;105892- 899Google ScholarCrossref
Little  PWilliamson  IWarner  GGould  CGantley  MKinmouth  AL Open randomised trial of prescribing strategies in managing sore throat.  BMJ. 1997;314722- 727Google ScholarCrossref
Del Mar  C Managing sore throat, a literature review, II: do antibiotics confer benefit?  Med J Aust. 1992;156644- 649Google Scholar
Gold  MRSiegel  JERussell  LBWeinstein  MC Cost-effectiveness in Health and Medicine.  New York, NY Oxford University Press1996;
American Academy of Pediatrics, Group A streptococcal infections. Peter  Ged. 1997 Red Book Report of the Committee on Infectious Diseases. 24th ed. Elk Grove Village, Ill American Academy of Pediatrics1997;483- 494Google Scholar
Gerber  MASpadaccini  LJWright  LLDeutsch  LD Latex agglutination tests for rapid identification of group A streptococci directly from throat swabs.  J Pediatr. 1984;195702- 705Google ScholarCrossref
McCusker  JJMcCoy  ELYoung  CLAlamares  RHirsch  LS Comparison of Directigen group A strep test with a traditional culture technique for detection of group A beta-hemolytic streptococci.  J Clin Microbiol. 1984;20254- 255Google Scholar
Mandell  GLPetri  WA  Jr Antimicrobial agents: penicillins, cephalosporins, and other β-lactam antibiotics. Hardman  JGLimbird  LEeds. Goodman & Gilman's the Pharmacological Basis of Therapeutics. New York, NY McGraw-Hill Book Co1996;1073- 1101Google Scholar
Weiss  MEAdkinson  NF  Jr β-lactam allergy. Mandell  GLBennett  JEDolin  Reds. Mandell, Douglas and Bennett's Principles of Infectious Diseases. New York, NY Churchill Livingstone1995;272- 278Google Scholar
deShazo  RDKemp  SF Allergic reactions to drugs and biologic agents.  JAMA. 1997;2781895- 1906Google ScholarCrossref
Tsevat  JWong  JBPauker  SGSteinberg  MH Neonatal screening for sickle cell disease: a cost-effectiveness analysis.  J Pediatr. 1991;118546- 554Google ScholarCrossref
Denny  FWWannamaker  LWBrink  WRRammelkamp  CH  JrCuster  EA Prevention of rheumatic fever: treatment of the preceding streptococcic infection.  JAMA. 1950;143151- 153Google ScholarCrossref
Stollerman  GH Penicillin for streptococcal pharyngitis: has anything changed?  Hosp Pract. 1995;3080- 83Google Scholar
Amigo  MCMartinez-Lavin  MReyes  PA Acute rheumatic fever.  Rheum Dis Clin North Am. 1993;19333- 350Google Scholar
Todd  J Rheumatic fever. Behrman  REKliegman  RMArvin  AMeds. Nelson Textbook of Pediatrics. 15th ed. Philadelphia, Pa WB Saunders1996;754- 760Google Scholar
Kaplan  EL Recent epidemiology of group A streptococcal infections in North America and abroad: an overview.  Pediatrics. 1996;97(suppl)945- 947Google Scholar
Kiselica  D Group A beta-hemolytic streptococcal pharyngitis: current clinical concepts.  Am Fam Physician. 1994;491147- 1154Google Scholar
Cockerill  FR  IIIMacDonald  KLThompson  RL  et al.  An outbreak of invasive group A streptococcal disease associated with high carriage rates of the invasive clone among school-aged children.  JAMA. 1997;27738- 43Google ScholarCrossref
Bennike  TBrøchner-Mortensen  KKjær  ESkadhauge  KTrolle  E Penicillin therapy in acute tonsillitis, phlegmonous tonsillitis and ulcerative tonsillitis.  Acta Med Scand. 1951;139253- 274Google ScholarCrossref
Finkler  SA The distinction between cost and charges.  Ann Intern Med. 1982;96102- 109Google ScholarCrossref
Not Available, Drug Topics Red Book.  Montvale, NJ Medical Economics Co, Inc1995;
Tsevat  JDuke  DGoldman  L  et al.  Cost-effectiveness of captopril therapy after myocardial infarction.  J Am Coll Cardiol. 1995;26914- 919Google ScholarCrossref
Kirschner  CGedBurkett  RCedKotowicz  GMed  et al.  Physicians' Current Procedural Terminology: CPT '95.  Chicago, Ill American Medical Association1994;
North  DAHeynes  RALennon  DRNeutze  J Analysis of costs of rheumatic fever and rheumatic heart disease in Auckland.  N Z Med J. 1993;106400- 403Google Scholar
Bureau of Labor Statistics Data, Nonfarm payroll statistics from the current employment statistics (national). Available at:; Accessed September 16, 1998.
Dajani  AS Adherence to physicians' instructions as a factor in managing streptococcal pharyngitis.  Pediatrics. 1996;97(suppl)976- 980Google Scholar
Snitcowsky  R Rheumatic fever prevention in industrializing countries: problems and approaches.  Pediatrics. 1996;97(suppl)996- 998Google Scholar
Green  SM Acute pharyngitis: the case for empiric antimicrobial therapy [editorial].  Ann Emerg Med. 1995;25404- 406Google ScholarCrossref
Pantell  RHBerwick  DM Cost-effectiveness analysis in pediatric practice [editorial].  Pediatrics. 1990;85361- 363Google Scholar
Pichichero  MEDisney  FATalpey  WB  et al.  Adverse and beneficial effects of immediate treatment of group A beta-hemolytic streptococcal pharyngitis with penicillin.  Pediatr Infect Dis J. 1987;6635- 643Google ScholarCrossref
El-Daher  NTHijazi  SSRawashdeh  NMAl-Khalil  IA-HAbu-Ektaish  FMAbdel-Latif  DI Immediate vs delayed treatment of group A beta-hemolytic streptococcal pharyngitis with penicillin V.  Pediatr Infect Dis J. 1991;10126- 130Google ScholarCrossref
Gilbert  DNMoellering  RC  JrSande  MA The Sanford Guide to Antimicrobial Therapy, 1998. 28th ed. Vienna, Va Antimicrobial Therapy, Inc1998;33
Bisno  ALGerber  MAGwaltney  JM  JrKaplan  ELSchwartz  RH Diagnosis and management of group A streptococcal pharyngitis: a practice guideline.  Clin Infect Dis. 1997;25574- 583Google ScholarCrossref
Schwartz  BMainous  AGMarcy  SM Why do physicians prescribe antibiotics for children with upper respiratory tract infections? [editorial].  JAMA. 1998;279881- 882Google ScholarCrossref
Froehlich  GWWelch  HG Meeting walk-in patients' expectations for testing: effects on satisfaction.  J Gen Intern Med. 1996;11470- 474Google ScholarCrossref