2.1. Design and sample

This study employed a cross-sectional survey to explain the relationships among presenteeism, mindfulness, and self-efficacy of primary medical staff. The data were collected from January to May 2017 using the general information questionnaire, the Five-Facet Mindfulness Questionnaire (FFMQ), General Self-Efficacy Scale (GSES), and the Stanford Presenteeism Scale (SPS-6). The developers permitted the usage of all questionnaires in this study. The selection criteria included primary medical staff with at least 1-year clinical experience in township hospitals or village clinics, and admitted by the administrative department for public health, who obtained corresponding qualifications and practice certificates. Participants had to understand the study objectives and provide written informed consent. The exclusion criteria include absence during the survey, such as those on leave, training, or maternity leave. Using a multi-stage cluster sampling method, the first stage considered Nanzheng County from among 10 counties in Hanzhong City of Shaanxi province as a first-order unit. The county's 18 township hospitals were divided into two groups according to economic level; better economic group and less developed group. The better economic group included 12 hospitals, from which we randomly selected 6 hospitals. The less developed group included 6 hospitals, from which we randomly selected 3 hospitals. Through the above sampling method, we obtained 9 hospitals as a second-order unit. In the third stage, we selected all medical staff in the 9 hospitals as the research subjects.