目標：過去有關轉診之研究多針對個案醫院或特定區域之轉診進行探討，缺少關於轉診的全國性研究。本研究使用健保資料庫分析分級醫療政策中，雙向轉診的「下轉」案件，探討醫療院所哪些特質與病患下轉後就醫與否及是否在下轉診所持續就醫（成功下轉）有關。方法：使用2018-2020年之全民健康保險資料，篩選出由醫院向下轉診至基層診所且主診斷為糖尿病之門診病患，根據後續就醫情形再區分為成功轉診組與未成功轉診組。本研究計算診所之醫療品質指標，分析醫療院所基本特性與醫療品質，與病患是否轉診就醫有關。因健保資料庫所能提供資訊有限，當病患被轉診後未至原定之轉診院所就醫，則無法得知原定的院所，因此本研究將分兩階段進行分析與探討。首先探討病患被下轉後，是否前往該下轉診所就醫的相關因素；第二階段則針對下轉至基層診所、且有就醫的病患進行分析。結果：病患過去曾至下轉診所就醫（OR=3.451）與成功下轉達統計上顯著差異，病患轉診前醫院層級為區域醫院及地區醫院，與成功下轉呈現負相關（區域醫院：OR=0.692、地區醫院：OR=0.622）。病患下轉至「糖化血紅素」（OR：1.523）、「血清肌酸酐」（OR：1.359）與「血清麩胺酸丙酮酸轉胺基脢」（OR：1.301）檢查比例高的診所，與成功下轉呈現正相關。結論：病患過去就醫經驗、轉診前醫院層級以及醫療品質與病患是否成功下轉有關，建議衛生主管機關針對提升下轉診所之醫療品質擬定轉診策略，以促進病患成功下轉的機會。

Objectives: Most studies regarding patient referrals in Taiwan have focused on individual hospitals or specific regions and thus have reported findings with limited generalizability. Consequently, the overall referral process remains unclear. Accordingly, this study analyzed downward referral patterns in the bidirectional referral system under Taiwan's hierarchical health-care policy. Relevant data were obtained from the National Health Insurance Research Database. We investigated whether patients sought medical care after downward referrals and whether they continued to receive medical care at referred facilities (i.e., successful downward referral). Methods: This study included patients with diabetes who were referred from hospitals to primary care clinics for treatment - a process known as downward referral. The patients were divided into two groups, namely successful and unsuccessful referral groups. Indicators of each clinic's health-care quality were analyzed to identify the correlation between health-care quality and downward referral. Because of data limitations, we could not identify referred clinics for patients who did not seek medical care despite referral. Thus, a two-part approach was adopted for analysis. First, we explored factors influencing patients' receipt of medical care at referred clinics. Second, we explored factors influencing continuation of care (at fewest two outpatient visits) at referred clinics. Results: Successful downward referral was significantly likely for patients who had previously visited a referred clinic (odds ratio: 3.451). However, the likelihood of successful downward referral was low for patients referred from regional or community hospitals (regional vs. community hospitals, odds ratios: 0.692 vs. 0.622, respectively). By contrast, this likelihood was high for patients who were referred to clinics with high proportions of hemoglobin A1C, creatinine, and alanine aminotransferase tests. Conclusions: Successful downward referral is associated with prior health-care experiences of patients, levels of clinics visited before referral, and quality of health care. Accordingly, health authorities are recommended to implement continual monitoring of referrals, develop referral strategies for health-care institutions of all levels, and enhance the quality of health care to improve the likelihood of successful downward referral.