Background: Currently, evidence-based medicine is widely propagated as a reference for proper clinical practice. As a result, there is an increasing need for more clinical trials based on Oriental diagnostic methods to evaluate the efficacy of Oriental medicine, including acupuncture and herbal medicine. The purpose of this study was to confirm which symptoms are adequate indicators of effects of Ojeock-san for lower back pain and develop a questionnaire to evaluate its effects. Methods: We interviewed 102 Oriental medical doctors working in Seoul with a preformed questionnaire which included questions about symptoms of lower back pain and indicators for Ojeock-san. We sampled respondents who answered that they trust the effectiveness of Ojeock-san in telephone survey carried out using multistage stratified random sampling technique from March to April, 2009. We categorized the respondents into two groups, differentiating them by gender, career, workplace, and trust level of Ojeock-san effect. Results: About half of the respondents selected 13 questions as the adequate indicators of Ojeock-san for low back pain. There were no differences in the top 11 selected indicators in total selection and top 3 ranking selection. The comparison of frequency of top 13 questions in total selections between the two groups showed no difference. Conclusions: There were 13 symptoms which were considered adequate indicators of effects of Ojeock-san for lower back pain found by many Oriental medical doctors. This questionnaire can be utilized as a diagnostic adjunctive tool, tested for validity and reliability of questionnaires through further studies.