The cornerstone of quality improvement involves the standardization of care, which has been shown repeatedly in history, and is a subject taken very seriously in an effort to protect the welfare of patients.

Quality improvement efforts can be followed back to the mid-1800s, when Ignaz Semmelweis in Vienna, Austria, established hand hygiene protocols after realizing that hospital-acquired diseases were transmitted via the hands of healthcare workers [1]. During the Crimean War in 1850, Florence Nightingale was credited with recognizing the association between high mortality rate among soldiers treated at army hospitals and poor ventilation, sanitation, and hygiene standards [2].

Ernest Amory Codman, considered the pioneer of outcome-based quality improvement, developed a system in which he would follow up with his patients for years after treatment and record the end result to determine the effectiveness of care. Dr. Codman’s concept influenced the founding of the American College of Surgeons (ACS) in 1917, and would eventually transform into the Hospital Standardization movement, a precursor to what we readily recognize today as The Joint Commission [3].

Avedis Donabedian, in 1966, described a conceptual framework for defining and assessing quality of healthcare services [4]. He identified three basic components essential to quality of care: structure, process, and outcome, emphasizing that properly integrating these components is critical in improving the quality of care.

Procedures for weight loss began in the 1950s with the introduction of the jejunoileal bypass (JIB ). However, the procedure was abandoned in the 1970s when a significant number of patients subsequently developed severe nutritional deficiencies, hepatic cirrhosis, and death. Reversal or conversion to another bariatric procedure was recommended in all patients who underwent a JIB procedure in order to prevent development or progression of these severe complications [5].

In 1966, Edward Mason performed the first gastric bypass connecting a loop of jejunum to the gastric pouch [6]. This technique was later modified in 1977, introducing the Roux-en-Y configuration to replace the loop gastrojejunostomy [7].

In 1971, Dr. Mason introduced the vertical-banded gastroplasty (VBG) in an attempt to avoid the complications associated with JIB [8]. Unfortunately, less than half of the patients maintained satisfactory weight loss after 5 years and many patients went on to require reoperations due to staple-line dehiscence, pouch dilation, band erosions, and weight loss failure [9].

In 1985, the inflatable gastric band was introduced and, in the 1990s, the sleeve gastrectomy was described as a component of the biliopancreatic diversion with duodenal switch procedure [10, 11].

Bariatric surgery became more widely accepted in 1990s as mounting evidence demonstrated durable weight loss and comorbidity remission . Case series using laparoscopic technique were published and there was a surging interest in learning this technique, sparking a major evolution in the field of bariatric surgery.

In 2001, the IOM report on complications among hospitalized patients focused concern around patient safety. The IOM published “Crossing the Quality Chasm: A New Health System for the Twenty-first Century,” a disheartening report revealing the flaws of our healthcare system. The report stated, “The quality of healthcare received by people of the United States fall short of what it should be [12].”

In 2005, a report by Flum et al. focused attention on the overall mortality in Medicare patients undergoing bariatric surgery, citing that the risk of early death after bariatric surgery is considerably higher than previously suggested [13].

After the introduction of laparoscopic bariatric surgery in 1994, there was a steady, practically exponential, increase in the number of surgeons performing laparoscopic bariatric surgery. Evaluation of the Nationwide Inpatient Sample between two time periods (1998 and 2002; 2003 and 2008) demonstrated that the rate of bariatric surgery increased from 6.3 to 32.7 to 54.2 procedures per 100,000 adults in 1998, 2002, and 2008, respectively. In 1998, only 2.1 % of all bariatric surgery procedures were completed laparoscopically. This proportion increased to 17.9 % in 2002, and greater than 90 % in 2008. The number of bariatric operations performed in 1998 was 12,775, which increased to 70,256 in 2002, peaked in 2004 at 135,985 cases, and plateaued at 124,838 cases in 2008. The number of bariatric surgeons with membership in the ASMBS increased from 131 in 1998 to 1819 in 2008 [14, 15].

Many surgeons would attend a 2- or 3-day course and start performing bariatric surgery without the appropriate infrastructure necessary to provide safe care for the patient. The numbers of complications realized were significant during this period, thus starting a frenzy of activity as prominent national newscasters were delivering negative news about bariatric surgery outcomes on a regular basis. Subsequently, the public and many payors were questioning the relevance and role of bariatric surgery as a means of treating morbid obesity . Many payors eventually stopped providing insurance coverage, deeming the procedures cost prohibitive due to high morbidity and mortality rates. Furthermore, surgeons would be subjected to skyrocketing malpractice insurance premiums if they elected to perform bariatric surgery. The future of bariatric surgery was in grave jeopardy, which necessitated critical scrutiny and improvement of the services being provided by bariatric surgeons if the specialty’s integrity and reputation were to remain intact.

In response, the ASMBS BSCOE and ACS BSCN programs decided to establish separate, but similar, accreditation programs to improve the quality of bariatric surgery care, in an effort to resolve the conflicts.

The ASMBS BSCOE was developed in 2004 to provide means to identify bariatric surgery programs providing high quality of care by administering comprehensive standardized surgical care, long-term follow-up, and management of the morbidly obese patient. Data was entered into the Bariatric Longitudinal Outcomes Database (BOLD).

In a parallel effort, the ACS, in 2005, gave highest priority for developing the Bariatric Surgery Center Networks (BSCN) to improve quality and facilitate access to care for morbidly obese patients. The ACS would recognize certain hospitals as Level 1a and 1b Bariatric Centers with high-volume practices that would manage the most challenging and complex patients with optimal opportunity for safe and effective outcome. Recognizing the need for access to bariatric surgery and recognizing that high-quality surgical care occurs in other than high-volume tertiary centers, they designated certain facilities as Level 2a and 2b Bariatric Surgery Centers that could provide high-quality care to a lower volume of risk-stratified patients with lower body mass index and less comorbidities. Outpatient Bariatric Surgery Centers would be designated to those centers that provided the application and adjustment of laparoscopic gastric bands with discharge from the unit in less than 24 h [16].

Both programs consisted of standards that provided an opportunity for bariatric surgery centers to develop the necessary infrastructure, process, and outcomes to improve their standards, education, and training to meet specific guidelines. Uniform data elements would be collected and outcomes compiled to provide programs with an opportunity to assess and verify risks and benefits of bariatric surgery. The majority of centers offering bariatric surgery in the USA participated in at least one of these accreditation programs. The data registries for both programs in 2011 had greater than 100,000 patients per year being entered into one of the two registries.

These programs likely contributed to improvements in bariatric surgery across the board as data from the Nationwide Inpatient Sample program revealed that bariatric surgery in-patient mortality dramatically improved from 0.8 % in 1998 to 0.21 % in 2003, and would decrease further to 0.1 % in 2008 [14, 15].

However, the existence of two accreditation programs created confusion and, in some cases, centers required duplicated effort in data collection. The accreditation programs proved to be biased and unintentionally restricted access to care. Programs were accredited based on structural and process elements only, not on outcomes, and the accreditation process could not truly differentiate between those programs that were “excellent” and those that were not.

The Center for Medicare and Medicaid Services (CMS) and some insurance payors would require one of these designations in order for bariatric surgery centers to provide care to beneficiaries within their network. As a result of this selective referral environment, many facilities offering high-quality bariatric surgery care would be excluded from participating due to difficulty meeting annual facility volume requirements. It was difficult for new programs to develop due to high-volume requirements, and more than one-third of programs were unable to meet the requirements to maintain accreditation.

In many cases, patients would be forced to leave their local communities to undergo surgery at centers hours away, just to return home and be treated by general surgeons with minimal or no bariatric surgery experience when complications developed. Studies looking at CMS’s policy limiting bariatric surgery coverage only to hospitals designated as “Centers of Excellence” (“COE”) found no difference in adjusted rates of complications and reoperations, as well as cost savings, in the time before and after the national coverage decision [17, 18]. This would eventually lead to a policy change in which patients are no longer required to undergo surgery only at programs participating in the ASMBS BSCOE or ACS BSCN [19]. This generated a debate regarding the importance of COE programs, as there was also data suggesting that COE centers were indeed the cornerstone of improving quality in bariatric surgery [20].

Additional shortcomings of these accreditation programs included the inefficiency and readability of the reports that were provided to the participating centers. The BOLD registry captured a large amount of rich data. However, the reports were not meaningful and readily understood in order for centers to assess their own performance compared to other centers. It was difficult to initiate quality improvement efforts as the reports lacked risk adjustment and benchmarking on outcomes, and definitions of data elements were vague. In addition, there were unacceptably low 30-day and long-term follow-up rates.

Regarding the volume requirement of 125 cases seen in the previous programs, evidence supported reducing the annual volume criteria to 50 stapling cases, thus keeping a balance of maintaining quality while not restricting access to care for morbidly obese patients [21].

The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) was established as a result of a government mandate to improve the quality of surgical care within the 133 Veterans Administration (VA) hospitals.

In 1985, there was a report citing disappointingly high mortality and complication rates in the VA hospital system. In 1986, Congress mandated that all VA hospitals report their outcomes annually and compare them with the national average. This effort was hampered due to the lack of national average data and risk-adjusted data models for various surgical specialties. The legislative act allowed for the development of a risk-adjustment model that would take into account the patient’s severity of illness in order to level the playing field for comparison. Between 1991 and 1993, VA surgeons developed the risk-adjustment models for 30-day mortality and morbidity in nine surgical specialties. In 1994, the VA NSQIP was created allowing for all VA hospitals to work in a collaborative manner and comply with the legislative mandate to monitor and improve surgical outcomes. Mortality and morbidity rates were reduced by 27 % and 45 %, respectively [22].

The VA NSQIP program proved to be so successful that, in 1999, the ACS initiated a pilot program involving 14 academic centers and 7 private community hospitals. The pilot study results validated the VA NSQIP results, and thus the ACS NSQIP was officially established in 2004 with support from AHRQ [23].

Currently, there are 640 hospitals participating worldwide, collecting data elements on preoperative risk factors, operative factors, and 30-day outcomes for morbidity and mortality. Risk-adjusted outcomes are presented to each hospital biannually, measuring observed versus expected (O/E) outcomes. Best practices are identified and shared with the participating hospitals. Participating hospitals have access to a wide variety of evidence-based service tools including best practice guidelines and case studies, risk calculator tool, and collaborative support.

ACS NSQIP has 13 regional collaboratives, 14 system-wide collaboratives, and 8 virtual/pilot collaboratives. One study showed that each year a hospital participates in the ACS NSQIP; it has the opportunity to reduce the number of complications by 250–500, and saves 12–36 lives. If every US hospital used ACS NSQIP, possibly more than 100,000 lives could be saved annually, and more than 2.5 million complications could be prevented, thereby potentially reducing costs by more than $25 billion [24].

In 2005, a regional model of collaborative quality improvement (CQI) gained traction in Michigan and led to successful QI in bariatric surgery and other areas as well.