The findings from this study showed that social support of the medical staff did not directly affect their sleep quality, but had an indirect through several paths or steps. Firstly, social support reduces anxiety and stress, and improves self-efficacy. Social support can help medical staff reduce anxiety levels, as friends or family members provide social and emotional support and share empathy [21]. Social interactions reduce negative emotions such as anxiety and can improve mood [22]. Currently, with the increase in the number of cases of COVID-19 infection in China, front-line medical staff are required to wear protective masks and protective clothing, which may cause added stress. When medical staff have a wide social network, social support can help to reduce stress by reducing the perception of the threat of stressful events and the physiological response and inappropriate behavior that can result from stress [23]. Social support contributes to improving self-efficacy, leading to more understanding, respect, encouragement, courage, and a sense of professional achievement [24]. Self-efficacy results in increased confidence to do the job well, and when combined with social support, members of the medical profession suffer less from loneliness and might be more optimistic, which improves coping mechanisms when under stress [25,26].