Objective  To examine the willingness for initial medication-seeking at grassroots institutions and referral and their influential factors among residents participating in different medical insurance in Shandong province for providing references to improve hierarchical diagnosis and treatment system.

  Methods  Face-to-face questionnaire surveys were carried out during January 2017 among 2 969 residents with different medical insurance randomly recruited with stratified sampling in urban and rural regions of 17 municipalities/prefectures across Shandong province.

  Results  Of the 2 965 respondents with valid information, 1 922 (64.8%) reported the willingness to seek medication first at grassroots institutions; 1 599 (53.9%) selected higher medical institutions for their referrals if necessary but 1901 (64.1%) selected lower medical institutions for their referrals under the condition when their illness being stable. The results of unconditional multivariate logistic regression analysis demonstrated that the respondents with following characteristics were more likely to report a higher willingness to seek medication first at grassroots institutions: with a grassroots medical institution near the home, agreeing with hierarchical diagnosis and treatment, considering hierarchical diagnosis and treatment being practicable, and ever taking medical services in community healthcare centers or township hospitals; while, the respondents with a mean annual household income of ≥ 20 000 yuan (RMB), with medical insurance for urban residents or commercial medical insurance, and ever having a referral were likely to report a lower willingness to seek medication first at grassroots institutions. The results also revealed that the respondents aged ≥ 65 years and with a mean annual household income of ≥ 10 000 yuan were more likely to have a higher willingness for a referral to higher grade medical institutions, while those with following characteristics were more likely to have a lower willingness for a referral to higher grade medical institutions: being female, living in rural regions, with grassroots medical institutions near their homes, agreeing with hierarchical diagnosis and treatment, considering hierarchical diagnosis and treatment being practicable, and ever taking medical services in community healthcare centers or township hospitals; in addition, the respondents being female, living in rural regions, agreeing with hierarchical diagnosis and treatment, considering hierarchical diagnosis and treatment being practicable, and ever taking medical services in community healthcare centers or township hospitals were more likely to have a higher willingness for a referral to lower grade medical institutions, but the respondents with a mean annual household income of ≥ 40 000 yuan were more likely to have a lower willingness for a referral to lower grade medical institutions.

  Conclusion  In Shandong province, the urban and rural residents with medical insurance have an inadequate cognition on hierarchical diagnosis and treatment and a lower willingness for initial medication-seeking at grassroots institutions; the residents′ willingness for initial medication-seeking at grassroots institutions and referral are mainly influenced by gender, age, mean annual household income, living region, type of medical insurance, whether with a grassroots medical institution near the home, the attitude towards hierarchical diagnosis and treatment and whether ever taking medical services in community healthcare centers or township hospitals.