Introduction
According to the Organisation for Economic Co-operation and Development (OECD) 2015 report, the United States (US) spends 16.4% of its Gross Domestic Product (GDP) on healthcare each year but does not see quality increases consistent with its spending.1 The US per capita spending is nearly double the average for similarly developed countries and yet the US underperforms on measures such as access, quality, equity, morbidity and mortality.1 By comparison, according to the OECD 2015 report, Sweden spent 11.1%, Canada 10.2% and the United Kingdom 8.5% of their respective GDPs on healthcare.1 Unless US healthcare leaders address soaring healthcare expenditures, a decreasing proportion of US citizens will be able to afford high-quality healthcare.2 When healthcare services are inefficient, they cost more, and fewer can benefit from the technical advances of modern medicine.2 Healthcare organizations are constantly challenged with discovering ways to reduce costs and improve quality. Volume, timeliness, diversity, safety and quality are factors directly impacting reimbursements and revenue cycle management. Length of stay (LOS) and wait times in healthcare organizations can be obstacles to providing efficient, high-quality care.
The value in healthcare has been conceptualized as "health outcomes per dollar spent and outcomes per dollar spent over time".3(p.74) The US Affordable Care Act of 2011 (ACA) is transitioning healthcare reimbursements from a volume-based to a value-based payment system, taking into account quality of care and cost containment.4 Length of stay and wait times in healthcare organizations are two issues that can directly affect value-based reimbursement. With the changes in healthcare payments, quality improvement (QI) initiatives have become a major factor in healthcare. Quality improvement can be defined as regular and continuous actions that lead to measurable improvement in healthcare services and the health status of targeted patient groups.5 Quality improvement initiatives can be diverse but share the common goal of improving the process, outcome and efficiency of complex systems of healthcare.6 An effective QI program can create a balance of quality, efficiency and profitability as it reaches organizational goals.5 The Lean process is a QI initiative that provides a framework to improve patient care by defining value as what a patient wants, mapping how the value flows to the patient and ensuring the competency of the process by making it time efficient and profitable.5 Quality improvement initiatives, such as the Model for Improvement and FADE (Focus, Analyze, Develop, Execute), examine existing methods and use cycles of interventions to achieve improvement.5
Lean is a QI process and set of principles originated by the Toyota Motor Company in the early 1990 s.3 The Lean process improves cycle times, defined as the total time from the beginning to the end of a process, and quality through the elimination of waste, which is defined as any activity that consumes resources without enhancing value to those being served by the process.7 Lean means creating more value for customers with fewer resources.8 A Lean organization understands customer value and focuses its key processes for increasing value continuously.8 Toussaint and Berry indicate that Lean "offers promise for improving quality and efficiency while controlling costs in the provision of optimum patient care".3(p.81) The implementation of Lean processes can improve the delivery and quality of patient services, and provide operational advantages to healthcare institutions. Increasingly, healthcare organizations are implementing Lean operational principles and practices.9 In efforts to bring their practices into compliance with the requirements of the ACA, some major US healthcare organizations are achieving improvements in patient safety while also reducing costs by applying Lean processes to existing systems and procedures.9
The Institute for Healthcare Improvement's Model for Improvement is a QI model that stemmed from the works of William Edwards Deming, who is known as the founder of continuous QI.5 This model begins by asking the questions: what are we trying to accomplish, how will we know a change is an improvement, and what changes can be made to result in improvements.5 The next step is the Plan-Do-Study-Act (PDSA) cycle to test changes in real work situations and is the most common rapid cycle process improvement tool in healthcare.5 Taylor et al. stated that "the pragmatic principles of PDSA cycles promote the use of a small-scale, iterative approach to test interventions, as this enables rapid assessment and provides flexibility to adapt the change according to feedback to ensure fit-for-purpose solutions are developed. Starting with small-scale tests provides users with the freedom to act and learn; minimize risk to patients, the organization and resources required and providing the opportunity to build evidence for change and engage stakeholders as confidence in the intervention increases."10(p.2) Finding effective QI methods to support continual development, and to test and evaluate interventions to care can be essential for delivery of high-quality and high-value care in a financially constrained environment.10 An advantage of this QI model is PDSAs allowing new learning to be built into the experimental process, which allows the theory being tested to be revised by building on the new knowledge, and a subsequent experiment can be conducted to see if it has resolved the problem and to identify if any further issues also need to be addressed.10
Length of stay and wait times in healthcare organizations are two factors that can directly affect patient satisfaction scores, which are currently used as one aspect of measuring quality for reimbursement. In the ambulatory care setting, prolonged wait times can negatively impact patient satisfaction scores.4 Improvements to clinic efficiency and elimination of wasteful practices can improve wait times.4 For example, in the emergency department (ED), door to doctor time affects wait times and LOS. El Sayed et al. conducted a study using Lean management processes to improve door to doctor time in the ED of the American University of Beirut, Lebanon, to improve wait times and decrease LOS.11 By focusing on value-driven Lean techniques rather than expense-reducing Lean techniques, the team used process mapping initially, followed by value stream mapping.11 Value stream mapping is a Lean process used to document, analyze and improve the flow of information or materials required to produce a product or service for a customer.4 The Lean process interventions led to a 37% wait times reduction in mean ED LOS of both admitted and discharged patients.11
Cohen et al. conducted a Model for Improvement QI initiative to reduce transferring wait times of critically ill patients from the ED to the medical intensive care unit (MICU).12 The impetus for the study was the concern that delayed transfer of critically ill patients from the ED to the MICU may be associated with longer hospital LOS.12 A team of frontline health care professionals including ED, MICU and supporting services mapped out existing practice patterns, determined causes for delays, and used the PDSA model to test changes.12 The QI interventions produced a 48% reduction in wait times for transfer from the ED to MICU and the length of stay for MICU patients admitted from the ED decreased by 16%.12 Cohen et al. stated that "the project demonstrated that such frontline efforts were feasible, successful, and sustainable and contributed to reduction in LOS".12(p.1337)
Creating and sustaining change in cultures and organizations can be difficult.12 The success of the Lean concept depends on an entire organizational culture that is receptive to Lean thinking. Quality improvement models, such as the Model for Improvement, face similar barriers. In order to be successful, the use of PDSA must be supported by a significant investment in leadership, expertise and resources for change.12 The conceptual simplicity of the PDSA framework can lead participants to taking on a PDSA initiative without properly investigating and framing a problem for improvement.12 Overlooking this step can waste a PDSA cycle or even result in failure of the project.
The purpose of this review is to explore the effectiveness of the Lean process compared to other quality improvement initiatives on LOS and wait times in healthcare organizations. The financial landscape of healthcare is transitioning, adding more pressures to reduce expenses in preparation for tighter margins. As previously mentioned, LOS and wait times in healthcare organizations are two issues that can directly affect value-based reimbursement. Identifying the most effective QI initiative for decreasing LOS and improving wait times will allow healthcare organizations to realize a balance of efficiency, quality and profitability.5 A preliminary search of literature was conducted in September 2016 and included the JBI Database of Systematic Reviews and Implementation Reports, Cochrane Database of Systematic Reviews, MEDLINE and PROSPERO. The preliminary search did not indicate any other systematic reviews completed or underway on this specific topic.
Inclusion criteria
Participants
The review will consider studies in all healthcare organizations utilizing quality improvement initiatives. Healthcare organizations may include but will not be limited to hospitals, rehabilitation centers and ambulatory care centers. Skilled nursing facilities will be excluded from the review.
Intervention
The review will consider studies on healthcare organizations utilizing the Lean process for quality improvement. Studies will need to explicitly state that a Lean process has been implemented to be included in the review. The duration of implementation will not be considered as a requirement.
Comparator
The review will consider studies that compare the intervention to healthcare organizations using other quality improvement initiatives. These may include but will not be limited to the Model for Improvement, PDSA and workflow process management.
Outcomes
The primary outcomes of this review will be LOS and wait times in healthcare organizations. The length of stay will be defined as the period from the day of admission to the day of discharge from a healthcare organization. Unit placement will not be considered a factor. This may include but will not be limited to the length of stay for hospitalization and ambulatory care centers. Wait times will include time spent in a waiting room, time waiting to see a provider, time waiting for a procedure, and time to discharge from a healthcare organization.
Types of studies
The review will consider experimental designs including non-randomized controlled trials, quasi-experimental, before and after studies, prospective and retrospective cohort studies, and case-control studies pertaining to the Lean process management and employee participation for inclusion. This review will also consider descriptive observational study designs including case series, individual case reports and descriptive cross-sectional studies for inclusion. Studies not undertaken for healthcare will be excluded.
Methods
Search strategy
The search strategy will aim to find both published and unpublished studies. An initial limited search of PubMed and CINAHL has been undertaken to identify articles on this topic, followed by analysis of the text words contained in the titles and abstracts, and of the index terms used to describe these articles. This informed the development of a search strategy including identified keywords and index terms which will be tailored for each information source. A proposed search strategy for PubMed and all other information sources are detailed in Appendix I. The reference list of all studies selected for critical appraisal will be screened for additional research. Studies published in or translated into the English language will be considered for inclusion in this review. Studies published from 2002 to present will be considered for inclusion in this review as the Lean concept was first described and used in healthcare in that year.9
Information sources
The databases to be searched will include: Academic Search Premier, Business Source Complete, CINAHL, Embase, Health Source: Nursing Academic Edition, PubMed and Scopus.
The search for unpublished studies will include: AHRQ.gov, Google Scholar, and ProQuest Dissertations and Theses.
Study selection
Following the search, all identified citations will be collated and uploaded into EndNote (Clarivate Analytics, PA, USA) and duplicates removed. Titles and abstracts will then be screened by two independent reviewers for assessment against the inclusion criteria for the review. Studies that meet the inclusion criteria will be retrieved in full and their details imported into the Joanna Briggs Institute's System for the Unified Management, Assessment and Review of Information (JBI SUMARI). The full-text of selected citations will be retrieved and assessed in detail against the inclusion criteria by two independent reviewers. Full-text studies that do not meet the inclusion criteria will be excluded, and reasons for exclusion will be provided in an appendix in the final systematic review report. Included studies will undergo a process of critical appraisal. The results of the search will be published in full in the final report and presented in a PRISMA flow diagram. Any disagreements that arise between the reviewers will be resolved through discussion, or with a third reviewer.
Assessment of methodological quality
Selected studies will be critically appraised by two independent reviewers at the study level for methodological quality in the review using standardized critical appraisal instruments from the Joanna Briggs Institute.13 Any disagreements that arise between the reviewers will be resolved through discussion, or with a third reviewer. The results of critical appraisal will be reported in a narrative form and in a table.
Data extraction
Data will be extracted from papers included in the review using the standardized data extraction tool available in JBI SUMARI by two independent reviewers.13 The data retrieved will include specific details about the interventions, populations, study methods and outcomes of significance to the review question and specific objectives. Any disagreements that arise between the reviewers will be resolved through discussion or with a third reviewer. Authors of papers will be contacted to request missing or additional data where required.
Data synthesis
Papers will, where possible, be pooled in a statistical meta-analysis using JBI SUMARI. Effect sizes will be expressed as either odds ratios (for dichotomous data) or weighted (or standardized) mean differences (for continuous data) and their 95% confidence intervals will be calculated for analysis. Heterogeneity will be assessed statistically using the standard chi-square and I2 tests. The choice of model (random or fixed effects) and method for meta-analysis will be based on the guidance by Tufanaru et al. 2015.14 Subgroup analyses will be conducted where there is sufficient data to investigate statistical variations of results among subgroups. Sensitivity analyses will be performed to test decisions made regarding study selection bias. Where statistical pooling is not possible, the findings will be presented in a narrative form including tables and figures to aid in data presentation where appropriate.
A funnel plot will be generated within JBI SUMARI to assess publication bias if there are 10 or more studies included in a meta-analysis.13 Statistical tests for funnel plot asymmetry (Egger test, Begg test, Harbord test) will be performed, where appropriate.
Assessing confidence
The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach for assessing confidence in the quality of evidence will be used for this review, with the results presented in a summary of findings table created using GRADEPro.
Appendix 1: Search strategy
PubMed
CINAHL
Academic Search Premier
Business Source Complete
Embase
Health Source: Nursing and Academic Edition
Scopus
Unpublished databases
Agency for Healthcare Research and Quality (AHRQ.gov)
Google Scholar
ProQuest Dissertations and Theses
References