背景和目的：分享決策 (shared decision-making) 是臨床服務工作不可分割的一部分。我們介紹如何以客觀分析來分享決策過程，以層級分析法 (analytic hierarchy process) 研究受試者對紫外線光敏感性測試 (photosensitivity testing) 劑量影響因子之權重判定。方法：本研究為橫斷研究，共有158 位健康成年人參與研 究。以層級分析法研究方式分析受試者對四種因素 (factors) 來決定影響光敏感性劑量測試劑量時，對不同因素 之重視程度。受試者必須先參加紫外線照射治療與紫外線光敏感性測試課程。研究時說明層級分析法研究方 式，包括決策的目的、各因素的標準以及兩兩因素相互比較重要性以達成決策目的。完成因素相互比較重要 性後，以幾何平均方法決定各影響因素之相對權重 (relative weights)。結果：受試者對因素比較具有一致判斷 (consistent judgment) 的比率為82.9%。以具一致判斷受試者對各影響因素之相對權重結果數據進一步分析，「避 免不良效果」與「避免重新測試」因素為最重要的兩個考量因素，其平均相對權重分別為0.37 ± 0.16 和0.26 ± 0.17。男女對各因素的權重並無顯著差異。當受試者為自己選擇照射比較久的測試時間時，顯示對「外觀」 因素比較不重視、對「避免重新測試」因素給予比較多的權重。階層式分群法 (hierarchical cluster analysis) 顯 示受試者可分為三群。結論：當考慮紫外線光敏感性測試劑量影響因子時，「避免不良效果」與「避免重新測 試」因素為最重要的兩個因素。臨床工作可利用層級分析法分享決策以及能精確瞭解病患的意見。

Background and Purpose: Shared decision-making is an integral part in clinical services. In order to introduce shared decision-making for photosensitivity testing (PST), we did analytic hierarchy process (AHP) to explore how perceived weights of the factors in PST. Methods: This was a cross-sectional study with healthy adults (n = 158). An AHP was used to study the weighting of the factors that influenced the selection of a dose series for PST. The participants received education programs on the responses to ultraviolet radiation and the method of PST. The AHP was instructed to participants, including the goal of the decision, criteria of the factors, and pair-wise comparison in achieving the goal. After finished the pair-wise comparison, geometric mean method was used to estimate the relative weights of the factors. Results: Participants with consistent judgment (82.9%) in factor comparisons were included for mean weight analyses. Avoidance of Adverse Effects and Avoidance of Retest (relative weights: 0.37 ± 0.16 and 0.26 ± 0.17, respectively) were the two most important factors. Gender had no significant difference in weighting the factors. Participants who chose the longer exposure time for themselves weighted Appearance as less important and Avoidance of Retest as more important. Hierarchical cluster analysis revealed three clusters of participants with different weighting priority. Conclusions: Avoidance of Adverse Effects and Avoidance of Retest are the two most important issues during selection doses for PST. Clinicians can utilize AHP for shared decision-making and obtaining clients’ opinions precisely.