Rescreening for Gonorrhea: An Evaluation of Compliance Methods and Results FRANKLYN N. JUDSON, MD, AND FREDERICK C. WOLF, BA
Abstract: To evaluate the cost-effectiveness of a routine rescreening (RS) culture several weeks after treatment for gonorrhea, as well as the specific efforts to ensure return visits, we followed 438 consecutive patiehts, 347 men and 91 women. Return visit compliance rates were 70 per cent for a test-of-cure culture, 27 per cent for a six-week RS, and 15 per cent at 12 weeks. The program detected seven cases of gonorrhea at $796 per case. In our clinic, RS is not a costeffective way to control gonorrhea. (Am J Public Health 69:1178-1180, 1979.)
The Venereal Disease Control Division of the Center for Disease Control (CDC) in Atlanta, GA, has recommended that additional efforts be made to follow-up patients treated for gonorrhea.* It is reasoned that patients who acquire gonorrhea at least once are those most likely to acquire gonorrhea again. To systematically evaluate the costs and benefits from intensified follow-up efforts, the Denver (Colorado) Metro Health Clinic (DMHC) conducted a prospective study of a sequence of methods for motivating patients to return for test-of-cure (TOC) and rescreening (RS) cultures. We also sought to better define patient characteristics associated with compliance behavior.
Methods From January 15 to April 7, 1976, 347 consecutive men and 91 consecutive women treated at the DMHC for un*Henderson, Ralph H: Commentary on National Strategies to Control Gonorrhea, July 1975. (Dr. Henderson was Director of the CDC Venereal Disease Control Division in 1975. The Commentary was included as part of his periodic "Dear Colleagues Letter" which was widely circulated.) From the Denver Metro Health Clinic, Disease Control Service, Denver Department of Health and Hospitals, and the Colorado Department of Health, Venereal Disease Control Unit. Address reprint requests to Franklyn N. Judson, MD, Director, Disease Control Service, City and County of Denver, Department of Health and Hospitals, 605 Bannock Street, Denver, CO 80204. Dr. Judson is also Assistant Professor of Medicine and Preventive Medicine, University of Colorado Medical Center. Mr. Wolf is Public Health Disease Control Representative. This paper, submitted to the Journal February 27, 1979, was revised and accepted for publication May 16, 1979. 1178
complicated anogenital gonorrhea were instructed to return for a TOC in three to five days and RS in six and 12 weeks. To obtain patient compliance, four motivational methods were used in a sequence determined by anticipated costeffectiveness (Figure 1). The clinician informed the patient about the complications of gonorrhea, initiated a contactcard system,' and explained the rationale for a TOC. When the patient returned for a TOC, the clinician explained the rationale for RS. At each visit, the patient was given an appointment card with the date entered for the next follow-up culture. We attributed any non-contact case detected duning a designated follow-up period to the most recently used motivational method. We did not attribute a gonorrhea case to RS efforts if the patient returned with symptoms before a scheduled appointment or at any time as a result of contact investigation. We compared the cost-effectiveness of each method based upon the unit cost of bringing a new case of previously undetected gonorrhea to treatment. Costs included clinician labor related to follow-up visits; secretarial labor in telephoning and filling out and posting letters; field investigator's labor and supervision; and the additional clinic visits generated at a 1976 average of $12.75 per visit. Indirect costs were not included. Gonorrhea was diagnosed by CDC recommended culture techniques.2 Patients were assigned by a random card system to receive the CDC recommended treatment schedule3 of procaine penicillin G, tetracycline hydrochloride, or spectinomycin. Women were not offered tetracycline and patients with a history of penicillin allergy received tetracycline (men) or spectinomycin (women).t Correlations were made between TOC compliance behavior and sex, race, sexual preference, age, marital status, and route of antibiotic administration.
Results Patients were statistically significantly (p < .05) more likely to return for a TOC if they were white, homosexual men, single (unmarried), and/or received intramuscular rather than per oral medication.** In general the associatEditor's Note: The "CDC Recommended Treatment Schedules, 1979" for both uncomplicated and complicated gonococcal infections are available from the Venereal Disease Control Division, Bureau of State Services, DHEW, PHS, CDC, Atlanta, GA 30333, as well as from most state and local public health departments. **Data available on request to authors AJPH November 1979, Vol. 69, No. 11
PUBLIC HEALTH BRIEFS
'
Patient returned within 3 clinic days of completed telephone call
The telephone reminder method fell short of its potential because 31 per cent of the patients did not provide a number (or did not want it used). Of those with usable numbers, only 27 per cent could be reached by one-time morning and afternoon calls. Eighteen per cent of our patients did not want us to use their addresses. Of 392 letters sent 23 (6 per cent) were returned by the post office. Except for 75 patients (19 per cent) who returned in response to the letter, the fate of the remaining 294 (75 per cent) letters could not be determined. A field investigator made 138 telephone calls and 349 field visits of which, respectively, 26 (19 per cent) and 46 (13 per cent) resulted in personal contact with the patient. Table 2 presents the estimated cost by motivational method of bringing a new case of previously undetected gonorrhea to treatment. In total, the RS program cost $5,570 to bring seven patients to treatment, or $796 per case.
-.90-
Patient returned within 5 clinic days of posting
Discussion
Patient returned within 3 clinic days of the
1. Clinican Motivation (appointment card)
appointment
Did not return within 3 clinic days 2. Telephone Reminder (morning and/or afternoon calls)
_
A) No telephone B) No answer or patient not available C) Call completed, but patient did not return within 3 clinic days I
3. Letter Reminder
tions between these patient characteristics and compliance were maintained for 6 and 12 week RS but the numbers were too small to demonstrate significance. Patient return rates and gonorrhea culture results by motivational method appear in Table 1.*** Of the 12 men with gonorrhea (nine from TOC and three from six-week RS visits) who did satisfy our inclusion criteria, seven (58.3 per cent) also complained of urethral discharge and might have returned to clinic in response to their symptoms rather than to our motivational efforts.
The concept of rescreening for gonorrhea appears on the surface to be reasonable, but to date, no critical evaluation of RS has appeared in the literature, although unpublished reports have been circulated internally by CDC. Variability in case definitions, patient populations, and methods do not permit a meaningful comparison of their results. To accurately assess RS outcome, it is essential to control for patients who returned to clinic in response to their symptoms or through contact investigation. We did not choose to include a control which is not asked to return for RS. The important bias that continuing or recurring urethral symptoms may have on the interpretation of compliance behavior is evident from a 1%2 Fulton County Health Department (Atlanta) study: which noted that only 53 per cent of men treated with antibiotics for gonococcal urethritis returned within two weeks for a TOC compared to 91 per cent of those given a placebo.4 All RS programs have been frustrated by compliance rates that fall precipitously over time. Patient characteristics significantly associated with low compliance rates existed in our population, but the differences were not large (e.g., blacks are 83 per cent as likely to comply as whites). Furthermore the data analysis was univariate compounding interpretation (e.g., in our clinic homosexual men are 96 per cent white while heteroxesual men are only 61 per cent white). We evaluated the cost-effectiveness of RS for each motivational method in terms of the unit cost of bringing a new case of previously undetected gonorrhea to treatment (Table 3). In order to interpret these results fairly, it should be noted that: 1) the study design challenges each successive
***Excluded from the results are 18 patients (15 men and three women) who returned with symptoms before a scheduled appointment or who stated they were contacts to gonorrhea. Eight (44.4 per cent) of the excluded patients were infected. Under less stringent criteria, these cases might have been falsely credited to the RS program.
tEthical considerations obviously prohibit replication of this 1962 study in 1979.
A) Insufficient address B) Letter not returned and patient did not return within 5 clinic days
I
4. Field Investigation (K2 phone calls and/ or .2 field visits)
K
---i
Patient returned within 5 clinic days of field investigation contact
A) Unable to locate patient B) Patient contact made, but patient did not return within 5 clinic days
Study closeout
FIGURE 1-Sequence of Four Methods Used to Encourage Patients Treated for Gonorrhea to Return for a Test-of-Cure and for Six-Week and 12-Week Rescreening Visits
AJPH November 1979, Vol. 69, No. 11
1179
PUBLIC HEALTH BRIEFS
TABLE 1-Return Rates and Gonorrhea Culture Results for 438 (347 Men and 91 Women) Patients Treated for Gonorrhea and Encouraged by a Sequence of Four Motivational Methods to Return for Test-of-Cure and for six- and 12-Week Rescreening Visits Follow-up Cultures
Test-of-Cure
Rescreen-6 weeks
Rescreen-12 weeks
Motivational Method Attributed to the Follow-up visit
No. (% of total) Retuming
No. (%) Positive
No. (% of total) Returning
No. (%) Positive
Clinician Motivation Telephone Reminder Letter Reminder Field Investigation Totals for all Methods
254 (82.8) 7 ( 2.2) 24 ( 7.8) 22 ( 7.2) 307 (70.1)-
8 ( 3-1) 0 ( 0.0) 0 ( 0.0) 6 (27.3) 14 ( 4.6)
60 (51.3) 7 ( 6.0) 33 (28.2) 17 (14.5) 117 (26.7)*
2 ( 3.3) 1 (14.3) 1 ( 3.0) 1 ( 5.8) 5 ( 4.3)
No. (% of total) No. (%) Returning Positive
35(53.8) 4 ( 6.1) 18(27.8) 8 (12.3) 65 (14.8)*
1 ( 2.9) 1 (25.0)
0 ( 0.0) 0 ( 0.0) 2 ( 3.8)
*Expressed as a per cent of the original 438 patients.
TABLE 2-Estimated Cost* by Motivational Method and by Follow-up Visit to Bring a New Case of Previously Undetected Gonorrhea to Treatment Follow-up Visit
Test-of-Cure Motivational Method
Total Cost
Clinician Motivation $3413 111 Telephone Reminder Letter Reminder 353 Field Investigation 2420
Rescreen-12 weeks
Rescreen-6 weeks
No. Cases Treated
Cost per Treated Case
Total
8 0 0 6
$427 NCt NCt
$ 888
403
Cost 121 478 2560
Total Visits
No. Cases Treated
Cost per Treated Case
Total Cost
No. Cases Treated
Cost per Treated Case
Cost per Treated Case
2 1 1 1
$ 444 121 478 3560
$497 63 250 713
1 1
$497 63 250
$ 436 147 1080 813
0 0
NCt
*Calculated by: labor costs + material costs + (No. patients returning x $12.75) + No. of patients with gonorrhea.
tNot able to calculate, denominator is zero.
motivational method with increasingly less compliant patients; 2) except for field investigations, the major cost consists of the added clinic visits by patients who did not have gonorrhea; and 3) the total number of new cases detected by RS was small (five men at six weeks and two women at 12 weeks). It appears that a telephone call is most cost-effective, followed by clinician motivation, a letter reminder, and field investigation. The total cost to detect seven cases of gonorrhea was $5,570 or $796 per case. Regardless of cost, infection rates of 4.3 per cent and 3.8 per cent at six and 12 weeks do not support the concept that RS can become a major element in Denver's gonorrhea control program. Only a much larger study would permit identification of patient subgroups who might still benefit from RS. We conclude that in our clinic setting and when performed according to our protocol, RS of either men or women for gonorrhea is not cost-effective. It remains to be demonstrated if RS is cost-effective in populations having a higher prevalence of gonorrhea and/or better compliance behavior. 1 180
REFERENCES 1. Judson FN, Wolf FC: Tracing and treating contacts of patients with gonorrhea in a sexually transmitted disease clinic. Public Health Rep 93:460-463, 1978. 2. Criteria and Techniques for the Diagnosis of Gonorrhea. Center for Disease Control, PHS, DHEW, Atlanta, GA, 1974. 3. Gonorrhea. CDC Recommended Treatment Schedules, 1974. Center for Disease Control, PHS, DHEW, Atlanta, GA, 1974. 4. Tiedemann JH, Hackney JF, Simpson WG, et al: Evaluation of tetracycline phosphate complex and other antibiotics in treatment of gonorrhea in males. Public Health Rep 77:485-490, 1962.
ACKNOWLEDGMENTS The authors gratefully acknowledge the contributory efforts of the Denver Metro Health Clinic staff, the field investigative work of Mr. Harold Hines, Dr. Richard Rothenberg and Mr. Arnold Maltz for assistance in compiling the data, and Ms. Pat Gallegos for secretarial assistance. The automated clinic data system is supported by a contract from the Operations Research Branch, Venereal Disease Control Division, Center for Disease Control, Atlanta, GA. An earlier version of this paper was presented at the 106th Annual Meeting of the American Public Health Association, Los Angeles, CA, October 1978.
AJPH November 1979, Vol. 69, No. 11
Abstract: To evaluate the cost-effectiveness of a routine rescreening (RS) culture several weeks after treatment for gonorrhea, as well as the specific efforts to ensure return visits, we followed 438 consecutive patiehts, 347 men and 91 women. Return visit compliance rates were 70 per cent for a test-of-cure culture, 27 per cent for a six-week RS, and 15 per cent at 12 weeks. The program detected seven cases of gonorrhea at $796 per case. In our clinic, RS is not a costeffective way to control gonorrhea. (Am J Public Health 69:1178-1180, 1979.)
The Venereal Disease Control Division of the Center for Disease Control (CDC) in Atlanta, GA, has recommended that additional efforts be made to follow-up patients treated for gonorrhea.* It is reasoned that patients who acquire gonorrhea at least once are those most likely to acquire gonorrhea again. To systematically evaluate the costs and benefits from intensified follow-up efforts, the Denver (Colorado) Metro Health Clinic (DMHC) conducted a prospective study of a sequence of methods for motivating patients to return for test-of-cure (TOC) and rescreening (RS) cultures. We also sought to better define patient characteristics associated with compliance behavior.
Methods From January 15 to April 7, 1976, 347 consecutive men and 91 consecutive women treated at the DMHC for un*Henderson, Ralph H: Commentary on National Strategies to Control Gonorrhea, July 1975. (Dr. Henderson was Director of the CDC Venereal Disease Control Division in 1975. The Commentary was included as part of his periodic "Dear Colleagues Letter" which was widely circulated.) From the Denver Metro Health Clinic, Disease Control Service, Denver Department of Health and Hospitals, and the Colorado Department of Health, Venereal Disease Control Unit. Address reprint requests to Franklyn N. Judson, MD, Director, Disease Control Service, City and County of Denver, Department of Health and Hospitals, 605 Bannock Street, Denver, CO 80204. Dr. Judson is also Assistant Professor of Medicine and Preventive Medicine, University of Colorado Medical Center. Mr. Wolf is Public Health Disease Control Representative. This paper, submitted to the Journal February 27, 1979, was revised and accepted for publication May 16, 1979. 1178
complicated anogenital gonorrhea were instructed to return for a TOC in three to five days and RS in six and 12 weeks. To obtain patient compliance, four motivational methods were used in a sequence determined by anticipated costeffectiveness (Figure 1). The clinician informed the patient about the complications of gonorrhea, initiated a contactcard system,' and explained the rationale for a TOC. When the patient returned for a TOC, the clinician explained the rationale for RS. At each visit, the patient was given an appointment card with the date entered for the next follow-up culture. We attributed any non-contact case detected duning a designated follow-up period to the most recently used motivational method. We did not attribute a gonorrhea case to RS efforts if the patient returned with symptoms before a scheduled appointment or at any time as a result of contact investigation. We compared the cost-effectiveness of each method based upon the unit cost of bringing a new case of previously undetected gonorrhea to treatment. Costs included clinician labor related to follow-up visits; secretarial labor in telephoning and filling out and posting letters; field investigator's labor and supervision; and the additional clinic visits generated at a 1976 average of $12.75 per visit. Indirect costs were not included. Gonorrhea was diagnosed by CDC recommended culture techniques.2 Patients were assigned by a random card system to receive the CDC recommended treatment schedule3 of procaine penicillin G, tetracycline hydrochloride, or spectinomycin. Women were not offered tetracycline and patients with a history of penicillin allergy received tetracycline (men) or spectinomycin (women).t Correlations were made between TOC compliance behavior and sex, race, sexual preference, age, marital status, and route of antibiotic administration.
Results Patients were statistically significantly (p < .05) more likely to return for a TOC if they were white, homosexual men, single (unmarried), and/or received intramuscular rather than per oral medication.** In general the associatEditor's Note: The "CDC Recommended Treatment Schedules, 1979" for both uncomplicated and complicated gonococcal infections are available from the Venereal Disease Control Division, Bureau of State Services, DHEW, PHS, CDC, Atlanta, GA 30333, as well as from most state and local public health departments. **Data available on request to authors AJPH November 1979, Vol. 69, No. 11
PUBLIC HEALTH BRIEFS
'
Patient returned within 3 clinic days of completed telephone call
The telephone reminder method fell short of its potential because 31 per cent of the patients did not provide a number (or did not want it used). Of those with usable numbers, only 27 per cent could be reached by one-time morning and afternoon calls. Eighteen per cent of our patients did not want us to use their addresses. Of 392 letters sent 23 (6 per cent) were returned by the post office. Except for 75 patients (19 per cent) who returned in response to the letter, the fate of the remaining 294 (75 per cent) letters could not be determined. A field investigator made 138 telephone calls and 349 field visits of which, respectively, 26 (19 per cent) and 46 (13 per cent) resulted in personal contact with the patient. Table 2 presents the estimated cost by motivational method of bringing a new case of previously undetected gonorrhea to treatment. In total, the RS program cost $5,570 to bring seven patients to treatment, or $796 per case.
-.90-
Patient returned within 5 clinic days of posting
Discussion
Patient returned within 3 clinic days of the
1. Clinican Motivation (appointment card)
appointment
Did not return within 3 clinic days 2. Telephone Reminder (morning and/or afternoon calls)
_
A) No telephone B) No answer or patient not available C) Call completed, but patient did not return within 3 clinic days I
3. Letter Reminder
tions between these patient characteristics and compliance were maintained for 6 and 12 week RS but the numbers were too small to demonstrate significance. Patient return rates and gonorrhea culture results by motivational method appear in Table 1.*** Of the 12 men with gonorrhea (nine from TOC and three from six-week RS visits) who did satisfy our inclusion criteria, seven (58.3 per cent) also complained of urethral discharge and might have returned to clinic in response to their symptoms rather than to our motivational efforts.
The concept of rescreening for gonorrhea appears on the surface to be reasonable, but to date, no critical evaluation of RS has appeared in the literature, although unpublished reports have been circulated internally by CDC. Variability in case definitions, patient populations, and methods do not permit a meaningful comparison of their results. To accurately assess RS outcome, it is essential to control for patients who returned to clinic in response to their symptoms or through contact investigation. We did not choose to include a control which is not asked to return for RS. The important bias that continuing or recurring urethral symptoms may have on the interpretation of compliance behavior is evident from a 1%2 Fulton County Health Department (Atlanta) study: which noted that only 53 per cent of men treated with antibiotics for gonococcal urethritis returned within two weeks for a TOC compared to 91 per cent of those given a placebo.4 All RS programs have been frustrated by compliance rates that fall precipitously over time. Patient characteristics significantly associated with low compliance rates existed in our population, but the differences were not large (e.g., blacks are 83 per cent as likely to comply as whites). Furthermore the data analysis was univariate compounding interpretation (e.g., in our clinic homosexual men are 96 per cent white while heteroxesual men are only 61 per cent white). We evaluated the cost-effectiveness of RS for each motivational method in terms of the unit cost of bringing a new case of previously undetected gonorrhea to treatment (Table 3). In order to interpret these results fairly, it should be noted that: 1) the study design challenges each successive
***Excluded from the results are 18 patients (15 men and three women) who returned with symptoms before a scheduled appointment or who stated they were contacts to gonorrhea. Eight (44.4 per cent) of the excluded patients were infected. Under less stringent criteria, these cases might have been falsely credited to the RS program.
tEthical considerations obviously prohibit replication of this 1962 study in 1979.
A) Insufficient address B) Letter not returned and patient did not return within 5 clinic days
I
4. Field Investigation (K2 phone calls and/ or .2 field visits)
K
---i
Patient returned within 5 clinic days of field investigation contact
A) Unable to locate patient B) Patient contact made, but patient did not return within 5 clinic days
Study closeout
FIGURE 1-Sequence of Four Methods Used to Encourage Patients Treated for Gonorrhea to Return for a Test-of-Cure and for Six-Week and 12-Week Rescreening Visits
AJPH November 1979, Vol. 69, No. 11
1179
PUBLIC HEALTH BRIEFS
TABLE 1-Return Rates and Gonorrhea Culture Results for 438 (347 Men and 91 Women) Patients Treated for Gonorrhea and Encouraged by a Sequence of Four Motivational Methods to Return for Test-of-Cure and for six- and 12-Week Rescreening Visits Follow-up Cultures
Test-of-Cure
Rescreen-6 weeks
Rescreen-12 weeks
Motivational Method Attributed to the Follow-up visit
No. (% of total) Retuming
No. (%) Positive
No. (% of total) Returning
No. (%) Positive
Clinician Motivation Telephone Reminder Letter Reminder Field Investigation Totals for all Methods
254 (82.8) 7 ( 2.2) 24 ( 7.8) 22 ( 7.2) 307 (70.1)-
8 ( 3-1) 0 ( 0.0) 0 ( 0.0) 6 (27.3) 14 ( 4.6)
60 (51.3) 7 ( 6.0) 33 (28.2) 17 (14.5) 117 (26.7)*
2 ( 3.3) 1 (14.3) 1 ( 3.0) 1 ( 5.8) 5 ( 4.3)
No. (% of total) No. (%) Returning Positive
35(53.8) 4 ( 6.1) 18(27.8) 8 (12.3) 65 (14.8)*
1 ( 2.9) 1 (25.0)
0 ( 0.0) 0 ( 0.0) 2 ( 3.8)
*Expressed as a per cent of the original 438 patients.
TABLE 2-Estimated Cost* by Motivational Method and by Follow-up Visit to Bring a New Case of Previously Undetected Gonorrhea to Treatment Follow-up Visit
Test-of-Cure Motivational Method
Total Cost
Clinician Motivation $3413 111 Telephone Reminder Letter Reminder 353 Field Investigation 2420
Rescreen-12 weeks
Rescreen-6 weeks
No. Cases Treated
Cost per Treated Case
Total
8 0 0 6
$427 NCt NCt
$ 888
403
Cost 121 478 2560
Total Visits
No. Cases Treated
Cost per Treated Case
Total Cost
No. Cases Treated
Cost per Treated Case
Cost per Treated Case
2 1 1 1
$ 444 121 478 3560
$497 63 250 713
1 1
$497 63 250
$ 436 147 1080 813
0 0
NCt
*Calculated by: labor costs + material costs + (No. patients returning x $12.75) + No. of patients with gonorrhea.
tNot able to calculate, denominator is zero.
motivational method with increasingly less compliant patients; 2) except for field investigations, the major cost consists of the added clinic visits by patients who did not have gonorrhea; and 3) the total number of new cases detected by RS was small (five men at six weeks and two women at 12 weeks). It appears that a telephone call is most cost-effective, followed by clinician motivation, a letter reminder, and field investigation. The total cost to detect seven cases of gonorrhea was $5,570 or $796 per case. Regardless of cost, infection rates of 4.3 per cent and 3.8 per cent at six and 12 weeks do not support the concept that RS can become a major element in Denver's gonorrhea control program. Only a much larger study would permit identification of patient subgroups who might still benefit from RS. We conclude that in our clinic setting and when performed according to our protocol, RS of either men or women for gonorrhea is not cost-effective. It remains to be demonstrated if RS is cost-effective in populations having a higher prevalence of gonorrhea and/or better compliance behavior. 1 180
REFERENCES 1. Judson FN, Wolf FC: Tracing and treating contacts of patients with gonorrhea in a sexually transmitted disease clinic. Public Health Rep 93:460-463, 1978. 2. Criteria and Techniques for the Diagnosis of Gonorrhea. Center for Disease Control, PHS, DHEW, Atlanta, GA, 1974. 3. Gonorrhea. CDC Recommended Treatment Schedules, 1974. Center for Disease Control, PHS, DHEW, Atlanta, GA, 1974. 4. Tiedemann JH, Hackney JF, Simpson WG, et al: Evaluation of tetracycline phosphate complex and other antibiotics in treatment of gonorrhea in males. Public Health Rep 77:485-490, 1962.
ACKNOWLEDGMENTS The authors gratefully acknowledge the contributory efforts of the Denver Metro Health Clinic staff, the field investigative work of Mr. Harold Hines, Dr. Richard Rothenberg and Mr. Arnold Maltz for assistance in compiling the data, and Ms. Pat Gallegos for secretarial assistance. The automated clinic data system is supported by a contract from the Operations Research Branch, Venereal Disease Control Division, Center for Disease Control, Atlanta, GA. An earlier version of this paper was presented at the 106th Annual Meeting of the American Public Health Association, Los Angeles, CA, October 1978.
AJPH November 1979, Vol. 69, No. 11
