Publication Date



Open access

Embargo Period


Degree Type


Degree Name

Doctor of Philosophy (PHD)


Interdisciplinary Studies (Graduate)

Date of Defense


First Committee Member

Vincent K. Omachonu

Second Committee Member

Donna E. Shalala

Third Committee Member

Steven G. Ullmann

Fourth Committee Member

Nurcin Celik


The purpose of this dissertation is to effectively understand, measure, and model the impact of Access to Care (AC) on Patient Safety (PS) through the creation of a model that evaluates their interdependence. Through the use of statistical tools and through the combination of variables that define patient access to health care and patient safety, a Patient Access and Safety (PACSA) index is developed. The calculated Patient Access and Safety index provides information to both providers and patients about the impact of access and safety on treatment outcomes. The input variables used to support this research are Patient Access Factors (PAF) (Age, Insurance Type, Visit Type, List Price, and Days To an Appointment) and Patient Safety Factors (PSF) (Severity of Diagnosis, Race, and Gender). In this model, 7,535 observations were used from a single organization based in South Florida, in order to develop the index. The PACSA index offers a tool that helps providers, healthcare staff and patients evaluate patient safety as it is impacted by access to healthcare through the calculated index. This index produces an equation that examines the relationship between access to care and patient safety using the following relationship: PACSA=∑_(i=0)〖(.645〖PSF〗_i- .645〖PAF〗_i )+0.399〗An extensive literature review identifies the connection between AC and PS and the relationships governing these two concepts. Although large organizations like the World Health Organization (WHO), Agency for Healthcare Research and Quality (AHRQ), and Institute of Healthcare Improvement (IHI) have studied these concepts independently, there has not been a study that used a factor or index to describe the relationship. As the healthcare delivery system becomes more complex, and consumers demand better treatment outcomes, there is a growing need to analyze these concepts jointly. This study focuses on diabetic retinopathy (DR). This is a condition experienced by chronic Diabetic patients, and it is one of the major causes of blindness (National Eye Institute, 2009). The increase in the occurrence of Diabetes worldwide has heightened the disease and inspired clinical research. In 2002, it was estimated that the disease stemming from Diabetes, namely DR, accounted for about 5% of world blindness, representing almost 5 million blind people. If left untreated or undetected, about 2% of people become blind, and about 10% develop severe visual impairment. By the year 2030, a possible 36 million people will have acute visual impairments and 7.2 million people will possibly be blind worldwide. In the United States, there are 18 million people with Diabetes, and 30% have Diabetic Retinopathy (5.3 million Americans over the age of 18) (ATA Report 2004; AHRQ, 2004; WHO, 2004). Although this study focused on DR, the model has been designed with the ability to be applied to other diseases and conditions. The goal of creating the PACSA index is to help healthcare workers understand when to schedule patients within the context of access and safety. Current appointment schedules, which are the tools used by healthcare workers, use a “New patient vs. Follow up patient” design. The PACSA challenges the current scheduling schema. No longer will patients be categorized into “New vs. Follow Up” visits. Instead, they will be evaluated for access to care requirements and patient safety needs from the initial point of entry into the health system. The recommendation is to start designing schedules based on PACSA (low PACSA, medium PACSA, and high PACSA). In this new paradigm, the low PACSA would describe patients that have low disease complexity, low number of risk factors, and can wait a little longer for their appointment without having complications of disease from lack of treatment. On the contrary, the high PACSA would include a subset of patients that have high disease complexity, high number of risk factors, and require immediate appointment and medical continuity of care to have the best treatments and outcomes. The PACSA index can serve as a visual guide for decisions regarding access and patient safety requirements. Two key components of quality within healthcare include access to care and patient safety. To create “congruent system integration” (Maier-Speredelozzi, 2007), there must exist synchronization of all healthcare delivery operations. The Patient Access and Safety Index (PACSA) provides a framework for integrating these two components. This research and the indices developed can offer benefits to health care organizations, patients, physicians, and government entities by providing a versatile tool to help improve access to health care and patient safety.


Access to Health Care, Access to Care, Patient Safety, PACSA index