The principal aim of the thesis is to define how the quality of hip fracture care should be measured and evaluated through a nationwide clinical hip fracture audit (chapter 1). To measure the quality of hip fracture care, adequate quality indicators are needed and the parameters in the audit database must be valid. Chapters 2 to 5 deal with quality indicators, while Chapter 6 addresses the validity of one of the audit database parameters. To evaluate the quality of hip fracture care the Dutch Hip Fracture Audit (DHFA) was developed. The initiation and the development of the DHFA are described in Chapter 7. Chapter 8 explores whether facilitators and barriers experienced by hospital staff were associated with hospital participation in the DHFA. The systematic data verification process of seven Dutch audits is described in Chapter 9. Based on the findings of the studies in this thesis, the general discussion (chapter 10) describes the most suitable measurements to assess the quality of hip fracture care through a clinical audit and whether the dataset of the DHFA in its present form is adequate to evaluate the quality of hip fracture care.Department of Trauma Surgery of the Leiden University Medical Center, Trauma Centrum West, Waleus Library of the Leiden University Medical Center, Dutch Institute for Clinical Auditing (DICA), and SOLV.LUMC / Geneeskund