Development of the Korean Medicine Core Outcome Set for Primary Dysmenorrhea (COS-PD-KM) for Herbal Medicine Treatment of Primary Dysmenorrhea in Primary Clinics

The aim of this study was to develop a Korean medicine (KM) core outcome set (COS) for primary dysmenorrhea to evaluate the effectiveness of herbal medicine (HM) in treating primary dysmenorrhea in patients visiting KM primary clinics. Previously reported outcomes were identified through a literature review to define outcomes and effect modifiers (EMs) for the questionnaire. Experts were invited to conduct modified Delphi consensus exercises, and primary care clinicians were invited to conduct Delphi consensus exercises to evaluate suitability and feasibility. Finally, an additional round of a modified Delphi exercise was conducted with experts to obtain a final agreement on the COS. Seventeen outcomes and 15 EMs were included from a literature review, and one effect modifier was suggested by the experts (Phase 1). In Phase 2, after the modified Delphi consensus exercises by experts, 10 outcomes and 11 EMs were included in the COS. The clinicians all agreed on the feasibility of COS (Phase 3). Finally, 10 outcomes and 6 EMs were included in the COS-PD-KM after the final modified Delphi consensus exercise (Phase 4). The effectiveness of HM used in primary clinics could be evaluated with this COS in patients with primary dysmenorrhea. Further studies that involve more relevant stakeholder groups, such as patient representatives and gynecological experts, are needed.