Table 1.

Components of analysis methodologies used to identify missed opportunities for preventing congenital syphilis (CS) through third-trimester screening and to evaluate its cost effect, Arizona, 2017-2018

CHEERSa component	Missed opportunities analysis	Effect analysis
Target population	Pregnant Arizona women with syphilis	Pregnant women enrolled in AHCCCS residing in greater Arizona (ie, excluding Maricopa County).
Study perspective	Statewide surveillance data, vital statistics data, and medical records were used to determine missed opportunities for preventing CS through a cascade of care focused on screening and treatment opportunities that were missed throughout pregnancy. The results from the missed opportunities analysis led to further analyzing third-trimester screening as a potential missed opportunity for preventing CS. Case classification was determined by using the CSTE definition of CS.21	AHCCCS data were used to determine the cost of covering an additional syphilis screening during pregnancy. The total number of pregnant AHCCCS members was estimated by using the AHCCCS Newborn Report for federal fiscal year (FFY) 2017 (unpublished report, AHCCCS, 2017).
Setting and location	Arizona	Greater Arizona (excluding Maricopa County)
Comparators	Once the cascade of care was complete and third-trimester screening was identified as a gap, Maricopa County data were used as a comparator for greater Arizona, and mothers whose health insurance agency was AHCCCS were used as a comparator with other mothers of infants with CS.	The analysis enumerated the additional screening and treatment costs after a change to the administrative code.
Time period	Mothers of infants with CS born from January 1, 2017, through June 30, 2018	FFY 2017
Choice of health outcomes	Evaluated health outcomes included the presence of prenatal care >45 days before delivery, syphilis screening >45 days before delivery, appropriate treatment initiated >30 days before delivery, and the existence of CS symptoms (despite appropriate screening and treatment).	The evaluated outcome was the cost of providing 1 additional screen per pregnant AHCCCS member in greater Arizona.
Estimating resources and costs	NA	The average cost per prenatal syphilis screen was estimated to be $6.59, using FFY 2017 reimbursement data for Current Procedural Terminology codes 86780, 86592, and 86593.25 The cost to treat most cases of adult syphilis, including pregnant women, was estimated to be $12.53 per case, using the average drug cost per AHCCCS penicillin claim during FFY 2017.
Assumptions	CSTE considers an infant born to a mother who initiated appropriate syphilis treatment >30 days before delivery to be ruled out as a CS case, unless the infant is symptomatic or has other criteria that meet the case definition for CS.21 A 15-day buffer was added to this threshold because surveillance data indicate that it can take an average of 2 weeks after the initial positive test result for Arizonan women to initiate treatment. Therefore, infants born to mothers with access to clinical services at least 45 days before delivery were considered to have preventable CS, and infants born to mothers who accessed care <45 days before delivery were considered to have CS that was not preventable.	The analysis adjusted for increased enrollment and reimbursement growth. An annual increase of 825 AHCCCS members per fiscal year was assumed. It was also assumed that all pregnant women insured by AHCCCS were insured throughout their pregnancy and would receive all recommended syphilis screenings. The model did not exclude women who were added to AHCCCS at delivery and missed their initial screening(s). In addition, because Maricopa County has had a Board Order recommending third-trimester screening since 2003, it was assumed that the expanded screening would affect only residents of greater Arizona, and Maricopa County residents were therefore excluded from the cost-effect analysis.
Analytic methods	Potential cases were classified by using the CSTE case definition.21 ADHS requested medical records for each infant with CS and the infant’s mother. Data from medical records and the vital records database were used to supplement missing information from the surveillance data and case investigation notes. Data were analyzed by using SAS version 9.4.20	Screening and treatment costs were multiplied by the number of pregnant members residing in greater Arizona, adjusted for enrollment and reimbursement growth by using historical enrollment data.

Abbreviations: ADHS, Arizona Department of Health Services; AHCCCS, Arizona Health Care Cost Containment System; CSTE, Council of State and Territorial Epidemiologists; NA, not applicable.

^aThe Consolidated Health Economic Evaluation Reporting Standards checklist is a 24-item checklist that serves as a guide for key items to include when reporting on health economic evaluations.²⁴