Background:  Patient safety is a major concern in the healthcare industry worldwide. Increasing patient safety is critical for avoiding negative outcomes in nursing care and achieving goals at the desired level of quality. One of the indicators of this quality care given to patient is known as missed care. Aim: Aims of this study to explore the factors influencing missed care in order to improve the quality of nursing care. Methods: This study is a systematic review that explores the factors influencing missed nursing care in hospitals. Meanwhile, the literature search was carried out in the CINAHL Pubmed, Ebsco, Science Direct, Proquest, Willey, Sage from 2017 to 2021. Results: The results from six databases (n=3702) were sorted into 22 collected articles which include 18 quantitative, 2 qualitative, and 2 mixed methods. These findings highlighted three factors that influence missed nursing care: a lack of staffing, nurse competency, and the working environment. Conclusion: The factors that  contribute with missed nursing care in hospitals include lack of nurse staff, competency, and work environment. As a result, the nursing manager's critical role is to create adequate nursing staff, improve their competency, and foster a positive work environment. Keywords: missed nursing care, lack of staffing, nurse competency,  working environment

Objective: This study aimed to examine the implications of continuous professional development and its impact on missed nursing care (MNC) in hospitals during the COVID-19 pandemic. Design: The method used was a sequential explanatory mixed design. Methods: This qualitative study included 29 nurses who participated in in-depth interviews and focus group discussions. All participants were interviewed over five semi-structured interviews, with quantitative data divided into factors influencing knowledge transfer practices and MNC surveys. The sample size for the quantitative research was 181 people. Results: Seven main themes were identified in the qualitative study: clinical learning activity in hospitals, need for motivation in learning, organizational leadership and support for continued professional development (CPD), obstacles in clinical learning, an overview of caring in nursing care, incidents of MNC, and expectations for CPD. The quantitative data show that nurses (n = 181) reported that one or more care activities had been left undone due to lack of time on their shift (31.5%), bell response (44%), and reviewing drug effectiveness (47.4%). The most common reasons for MNC are an inadequate number of staff, inadequate shift-to-shift handoff, and communication breakdown within the nursing team. Conclusion: There were numerous incidents of MNC in hospitals during the COVID-19 pandemic. Increased CPD awareness can provide nurses with knowledge about MNC in nursing care.