Table of Contents

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Hospitals and Ambulatory Surgery Centers

Methodology for Charges – Inter-Quartile Ranges

Background
Many insurance plans have traditionally utilized a standard deviation based methodology for the development of outlier thresholds for inpatient services.  Due to the fact that the distribution of hospital days within any DRG category is not normally distributed, the inter-quartile range is an approach that does not rely on statistics based upon a normal distribution and would offer a more technically sound alternative.  The inter-quartile range is a measurement commonly used for working with non-parametric data as a means of delivering more defensible results.

Rationale
The distribution of facility data is non-parametric in that variables such as length of stay, costs, and charges have more variation at the high-end of the data sets.  This means that the distribution of data above the median value produces a much flatter curve than that below the median value.  Figure 1 graphically depicts the differences between parametric and non-parametric distributions of data.

The inter-quartile range represents the width of an interval which contains the middle fifty percent of the hospital data.  The inter-quartile range, therefore, is a distance, not an interval, and it is a measure of the spread of the data.  Because of this it is less affected by high outliers in the data set.  Using the inter-quartile range methodology discounts the impact that large outlier values have on measuring the dispersion of data variables.  For the type of data being analyzed, it is a more stable statistic than the standard deviation.

Methodology
The inter-quartile range represents the width of an interval which contains the middle fifty percent of the data; stated alternatively, since 25% of the data are less than or equal to the first quartile and 25% are greater than or equal to the third quartile, the inter-quartile range is the length of an interval that includes about half of the data.  This difference is measured in the same unit as the data.

To determine the inter-quartile range, all data are organized from least to greatest value.  The first quartile, denoted as Q1, is the set of data having the property that at least one-quarter of the observations are less than or equal to Q1 and that at least three-quarters of the data are greater than or equal to Q1.  The third quartile, denoted as Q3, is conversely identified.

To determine the inter-quartile range (IQR), the spread of the difference between Q1 and Q3 is measured:

IQR = Q3 - Q1

 

Hospitals

Methodology for Adjusting Length of Stay

The data is risk adjusted for patient severity in order to allow for meaningful comparisons. The primary reason for risk adjustment is to remove the long-standing and valid criticism that evaluative comparisons of two or more disparate groups based on observed reported data is often not an effective methodology due to differences in case-mix between the groups under study. This criticism in simpler terms is the "our patients are sicker than their patients" response.

In order to understand how data is adjusted for severity and case mix, three concepts must be introduced; observed value, expected value, and risk adjusted.

Important - The time period for adults represents January 2008 – December 2008 data and pediatrics uses 3 years of data January 2006 – December 2008.

Observed Value

This is the reported value. For example, the observed average length of stay for a hospital is calculated by taking the total inpatient days for all patients and dividing this total by the total number of cases. The values used for days and cases are taken from information reported by the hospital to the Agency for Health Care Administration (AHCA).

Expected Value

Expected values are severity adjusted according to case mix, using 3M's All Patient Refined Diagnosis Related Groups (APR-DRGs) as the methodology for severity adjustment.

Note: Expected value calculations for adults are APRDRG and age group specific for each product line age group. Expected value calculations for pediatrics are APRDRG and age group specific for each product line age group. Also, the values for pediatrics are based on three years of data, January 2006 – December 2008.

Before proceeding to an example of an expected value calculation, we need to first describe the APR-DRG patient classification and severity assignment process.

Medicare DRGs and APR-DRGs are patient classification systems with a primary objective of grouping types of patients treated by the resources they consume. 3M's APR-DRGs build upon these systems by going beyond the simple assignment of a base DRG by also assigning to each case a severity of illness, defined as:

Severity of illness: the extent of physiologic decompensation or organ system loss of function

Severity of illness subclasses are numbered as either 1 (minor), 2 (moderate), 3 (major), or 4 (extreme).

Assignment of severity of illness subclasses is based upon a number of factors, including the underlying base APR-DRG assignment (determined by principal diagnosis, procedures, age, sex and discharge status), secondary diagnoses, and interactions amongst diagnoses.

The advantage of APR-DRGs is that they acknowledge differences in severity of illness among patients within a single APR-DRG, as fits with our real world understanding. For example, some pneumonia patients are much sicker than others, even though they may all be classified under the same DRG.

So how does this website use APR-DRGs in calculating expected values? Each inpatient case is assigned an expected value which is the average value for that case's designated APR-DRG and severity of illness level across the State of Florida. For example, a case is designated as a Simple Pneumonia (APR-DRG 139) with a severity of illness level 2. The state average length of stay for all Simple Pneumonia (APR-DRG 139) with severity of illness level 2 is 5.5 days. The expected value for this specific case's length of stay would then be 5.5 days.

Calculations:

Hospital's Observed ALOS:

Total hosp. days for the selected condition / total hosp. cases for the selected condition

Hospital's Expected ALOS:

Average of the expected hosp. length of stay for all cases for the selected condition at the hospital

Risk Adjusted Value

The risk-adjusted average length of stay is the best estimate, based on the statistical model, of what the provider's length of stay would have been if the provider had a mix of patients identical to the statewide mix. The risk adjusted value is the observed length of stay divided by the expected length of stay and multiplied by the state of Florida's average length of the stay for a medical condition/procedure.

Hospital's Risk adjusted ALOS:

Observed ALOS for the selected condition / Expected ALOS for the selected condition * State ALOS for the selected condition = Risk Adjusted ALOS

Methodology for Potentially Preventable Readmissions (PPRs) and APR DRGs:

Statistical Methods

Introduction

The 3M™ APR™ DRG classification system categorizes patients based on their severity of illness and risk of mortality. In version 25.0 of the APR DRG classification system, there are 314 APR DRG categories, each of which is subdivided into four subclasses for a total of 1,356 unique patient categories.

Potentially Preventable Readmission (PPRs) identify return hospitalizations that may have resulted from the process of care and treatment (readmission for a surgical wound infection) or lack of post admission follow-up (prescription not filled) rather than unrelated events that occur post admission (broken leg due to trauma).

In computing a hospital PPR rate, the numerator is defined as the number of initial admissions with one or more qualifying clinically related readmissions within a given time period.  The denominator of a readmission rate is identified as the number of initial admissions at risk for a potentially preventable readmission, excluding deaths and admission meeting the criteria for one or more global exclusions occurring in the index hospitalization, for the related population for the same time period.

the number of initial qualifying admissions with one or more PPRs

divided by

the number of admissions at risk for a PPR

Rates of PPR occurrence can be calculated for each APR DRG category by severity of illness level.  A PPR rate for each APR-DRG by severity level was developed for each of these three age groups based on a 15 day readmission window for readmissions across hospitals.  These rates are typically referred to as norms because they reflect the experience of groups of hospitals.

Using APR DRG categories to control differences in the clinical characteristics between their patients or those of the norm, individual hospitals can compare their PPR rates to those of the normative data. These comparisons will enable them to determine if and how their performance differs from comparable hospitals. A provider’s experiences and those of normative populations are likely to be different. This can represent a true difference or can be caused by normal variation. Statistical techniques can be used to determine which of the observed differences in outcomes are most likely to be true differences and which are probably the result of natural variation.

Observed Value

The observed readmission rates are calculated for each condition or procedure by dividing the number of initial discharges with one or more Potentially Preventable Readmissions, PPRs, by the total number of initial discharges. The AHCA normative database (state values) are calculated for each APR DRG and severity of illness subclass the same. The PPR is calculated as follows:

Let:
N = observed rate
P = Number of initial discharges with one or more PPRs
D = Number of initial discharges at risk for a PPR
i = condition or procedure or an APR DRG category and a single severity of illness level

This number is displayed as PPRs per initial discharge to facilitate the calculations in the expected value computation example below.  Data from April 2006 – March 2007 was used to compute PPR observed rates. 

Expected Values

The expected value of PPRs is the number of readmission chains (initial discharge with a PPR) a hospital, given its mix of patients as defined by APR DRG category and severity of illness level, would have experienced had its rate of PPRs been identical to that experienced by a reference or normative set of hospitals.

The technique by which the expected value or expected number of PPRs is calculated is called indirect standardization. For illustrative purposes, assume that every initial discharge can meet the criteria for having a PPR, a condition called being “at risk” for a PPR. All initial discharges will either have no PPRs or will have a chain of one and possibly more PPRs.

Once a set of PPR normative rates has been calculated by APR-DRG by SOI, it can be applied at the APR-DRG and SOI level to individual hospitals to compute the expected PPR rate for the hospital.  Then the PPR expected rate is adjusted for age over 85 and the presence of a major mental health problem as a comorbid condition. These adjustments were computed from the AHCA normative database for each of the three age groups.

Consider the following example for computing a hospital’s expected PPR rate.  For each APR-DRG by severity subclass, a normative PPR rate has been computed from the normative database.  Hospital AAA has 11 initial discharges in the database.  One of these initial discharges was globally excluded from the PPR computations because the patient left against medical advice.  Of the remaining 10 initial discharges, one of these initial discharges had a potentially preventable readmission within the defined readmission window.  The other nine initial discharges either did not have a subsequent admission within the defined readmission window or there was a subsequent readmission within the defined readmission window, however, the readmission was not identified as potentially preventable and therefore clinically excluded from being considered a PPR.  

The providers actual PPR rate is the number of initial discharges with one or more PPRs within the readmission window divided by the number of initial discharges at risk for a PPR (not globally excluded).  Provider AAA PPR rate equals 1 divided by 10 = 10%.  The expected PPR rate based on the initial discharges at risk for a PPR is the sum of the associated APR-DRG by SOI normative PPR rate times the mental health and age adjustment factor divided by the number of initial discharges at risk for a PPR.

Risk Adjusted Value

It is not meaningful to compare expected values across hospitals. Thus, if one hospital has a higher expected value than another hospital, no conclusion can be made regarding the relative performance of the two hospitals. In order to directly compare the performance of two hospitals a risk adjusted value can be computed.  In other words, the expected value is relative to the hospital’s actual value while the risk adjusted value is relative to actual value in the reference database. Thus the risk adjusted value can be compared across hospitals.  The risk adjusted value is computed as follows:

                                        Hospital Actual PPR Rate
Risk Adjusted PPR Rate = -----------------------------------------  X Reference Actual PPR Rate
                                        Hospital Expected PPR Rate

The reference actual PPR rate is the overall PPR rate for the hospitals being compared.  If analysis is performed for a subset of cases, say cardiac surgical APR DRGs, then the overall PPR rate for all cardiac surgical APR DRGs would be the reference actual PPR rate from which a hospitals actual to expected PPR rate for cardiac surgical APR DRGs would be adjusted.

Statistical significance

The statistical techniques calculate the probability that an observed difference in performance between the provider and the norm is due to natural variation. A difference in performance between provider and norm is considered “significant” if the probability that a difference is due to natural variation is small. A difference is considered significant at the 0.05 level if the probability that the observed difference is due to natural variation is five percent or less (i.e., less than one chance in twenty).

Three interrelated factors determine whether a difference in performance is significant: the number of observations, the magnitude of the observed difference in performance, and the variability in performance of the hospital and of the norm. A small number of patients, a small observed difference in performance, or high variability within either the provider or the norm (i.e., high standard deviation) increase the probability that the observed difference is due to chance and does not represent a true difference. Conversely, a large number of patients, a large observed difference between provider and norm, or low variability within both hospital and norm make it more likely that the difference was not due to chance and does represent a true difference.

Further, an observed difference of the same magnitude may be significant in one comparison and not in another. The conclusion that a difference is significant indicates that the hospital and the norm have had true difference in performance.

There are several possible reasons why a difference may not be significant. There may be no true difference, and thus, no significant difference in performance is found. Alternatively, there may be too few observations or too much variability, or both, so that even a true difference cannot be detected. Thus, a difference which is not significant does not necessarily mean that there is no true difference in performance. It may simply mean that there were too few patients or too much variability to conclude that the observed difference was not due to chance.

The comparison of a provider’s performance to a norm requires the use of several distinct statistical methods. Outcome variables such as PPR rates are binary variables that indicate the occurrence or non-occurrence of an event such as a readmission following an initial discharge. Comparisons can be performed for data from a single APR DRG category and subclass, or they can be performed for data pooled across multiple APR DRG categories and subclasses.

Test of Significance

For binary data such as readmission, a test of significance of the difference between the actual and expected values can be performed by comparing readmission rates separately within each APR DRG category and subclass and then pooled across APR DRG categories and subclasses. The calculation of statistical significance for PPRs uses the Cochran-Mantel-Haenszel test (CMH) to calculate statistical significance for PPRs across APR DRG categories and severity of illness levels.

To test for statistical significance, it is assumed that the APR DRG category and severity of illness level for each initial discharge is known, as well as whether or not a PPR occurred within the window following the initial discharge. The tests of significance are to be calculated with only initial discharges at risk for PPRs.  In computing the test of significance, the normative statistic should take into account the adjustment for age over 85 and the presence of a major mental health problem as a comorbid condition based on hospital’s cases.

To calculate a CMH statistic, start with the 2 * 2 matrix used for the Chi Square test. The CMH statistic uses the data from one corner of the matrix and the marginals. It does not matter which corner; all will produce the same results. To simplify matters, we will use the upper left hand corner.

Calculate the expected value and variance of each cell.

The expected value is calculated as follows:

The variance is calculated as follows:

After, the expected value and variance are calculated, calculate the CMH statistic as follows:

As the CMH statistic has a chi square distribution with 1 degree of freedom the following significance levels can be used:

Significance Level	Х2
.1	2.7055
.05	3.8415
.01	6.6349

For the purposes of reporting statistical significance a significance level of .05, Ð¥² => 3.8415, was used. In addition, statistical significance will not be calculated if the overall number of initial discharges at risk for PPRs is less than forty or if the number of observed or expected initial discharges with PPRs is less than five for a provider. 

Hospital Inpatient Medical Conditions and Procedures - Adults

Bones and Joints

Back Problems

Back Problems – APR-DRG code 347

Disc Surgery

Disc Surgery – APR-DRG code 310

Femur Fracture Surgical Repair

Femur Fracture Surgical Repair – APR-DRG code 308

Fracture of Pelvis or Dislocation of Hip

Fracture of Pelvis or Dislocation of Hip – APR-DRG code 341

Hip Replacement

Hip Replacement - APR- DRG code 301

Knee Replacement

Knee Replacement – APR-DRG code 302

Leg Amputation

Leg Amputation – APR- DRG code 305

Shoulder, Upperarm and Forearm Procedures

Shoulder, Upperarm and Forearm Procedures – APR- DRG code 315

Spinal Fusion

Spinal Fusion – APR-DRG codes 303, 304 and 321

Tibia/Fibula Fracture Repair

Tibia/Fibula Fracture Repair – APR- DRG code 313

Brain and Nervous System

Craniotomy (brain surgery)

Craniotomy (brain surgery) – APR-DRG codes 20 and 21

Stroke

Stroke – APR-DRG codes 44 and 45

Transient Cerebral Ischemia

Transient Cerebral Ischemia – APR-DRG code 47 

Cancer

Acute Leukemia

Acute Leukemia – APR-DRG code 690

Bone Marrow Transplant

Bone Marrow Transplant – APR-DRG code 3 

Brain Cancer

Brain Cancer – APR-DRG code 41

Chemotherapy

Chemotherapy – APR-DRG code 693 

Digestive System Cancer

Digestive System Cancer – APR-DRG code 240

Female Reproductive Cancer

Female Reproductive Cancer – APR-DRG code 530

Kidney / Ureter Removal

Kidney / Ureter Removal – APR-DRG code 442 

Leukemia / Lymphoma, Non - Surgical

Leukemia / Lymphoma, Non - Surgical – APR-DRG code 691 and 694

Leukemia / Lymphoma, Surgical

Leukemia / Lymphoma, Surgical – APR-DRG code 681 

Liver/Pancreatic Cancer

Liver Cancer – APR-DRG code 281 

Lung Cancer

Lung Cancer – APR-DRG code 136

Mastectomy

Mastectomy – APR-DRG code 362 

 

Diabetes/Endocrinology/Metabolism

Diabetes

Diabetes – APR-DRG code 420

General Medical Information

Acute Pancreatitis

Acute Pancreatitis – APR-DRG code 282

Cellulitis

Cellulitis – APR-DRG code 383

Convulsions (Seizures)

Convulsions (Seizures) – APR-DRG code 53

Diverticulosis / Diverticulitis

Diverticulosis / Diverticulitis – APR-DRG code 244

Gastrointestinal Hemorrhage

Gastrointestinal Hemorrhage – APR-DRG codes 241, 242 and 253

Hypovolemia (Low Blood Volume)

Hypovolemia (Low Blood Volume) – APR-DRG code 422 

Inflammatory Bowel Disease

Inflammatory Bowel Disease – APR-DRG code 245

Migraine and Other Headaches

Migraine and Other Headaches – APR-DRG code 54

Non-Bacterial Gastroenteritis, Nausea and Vomiting

Non-Bacterial Gastroenteritis, Nausea and Vomiting – APR-DRG code 249 

Renal Failure

Renal Failure – APR-DRG code 460 

Septicemia (blood poisoning)

Septicemia (blood poisoning) – APR-DRG codes 720 and 724

Sickle Cell Disease

Sickle Cell Disease – APR-DRG code 662 

Syncope (fainting)

Syncope (fainting) – APR-DRG code 204

Urinary Stones

Urinary Stones – APR-DRG code 465

Urinary Tract Infection

Urinary Tract Infection – APR-DRG code 463 

Heart and Circulatory System

Angina Pectoris and Coronary Atherosclerosis

Angina Pectoris and Coronary Atherosclerosis – APR-DRG codes 198

Angioplasty

Angioplasty – APR-DRG codes 174 and 175 

Cardiac Catheterization

Cardiac Catheterization – APR-DRG codes 191 and 192

Cardiac Defibrillator and Heart Assist Anomaly

Cardiac Defibrillator and Heart Assist Anomaly – APR-DRG code 161

Cardiac Pacemaker Implant

Cardiac Pacemaker Implant – APR-DRG code 171 

Cardiac Valve Procedures without Cardiac Catheterization

Cardiac Valve Procedures without Cardiac Catheterization – APR-DRG code 163

Chest Pain

Chest Pain – APR-DRG code 203 

Coronary Bypass Surgery

Coronary Bypass Surgery – APR-DRG codes 165 and 166 

Heart Attack

Heart Attack – APR-DRG code 190 

Heart Failure

Heart Failure – APR-DRG code 194 

High Blood Pressure

High Blood Pressure – APR-DRG code 199

Irregular Heartbeat

Irregular Heartbeat – APR-DRG code 201

Major Thoracic and Abdominal Vascular Procedures

Major Thoracic and Abdominal Vascular Procedures – APR-DRG code 169

Peripheral Vascular Disease (PVD)

Peripheral Vascular Disease (PVD) – APR-DRG code 197 

Pulmonary Edema and Respiratory Failure

Pulmonary Edema and Respiratory Failure – APR-DRG code 133

Asthma

Asthma – APR-DRG code 141

Chronic Obstructive Pulmonary Disease, COPD (pulmonary disease)

COPD (pulmonary disease) – APR-DRG code 140

Lung and Chest Procedures

Lung and Chest Procedures – APR-DRG codes 120 and 121

Pneumonia

Pneumonia – APR-DRG code 139

Pneumonitis, Aspiration

Pneumonitis, Aspiration – APR-DRG codes 137

Surgery

Appendectomy

Appendectomy – APR-DRG code 225

Arteriovenostomy (renal dialysis)

Arteriovenostomy (renal dialysis) – APR-DRG code 444 

Gall Bladder Removal

Gall Bladder Removal – APR-DRG 262

Heart and/or Lung Transplant

Heart and/or Lung Transplant – APR-DRG code 2 

Hernia Repair

Hernia Repair, Other – APR-DRG code 227

Inguinal, Femoral and Umbilical Hernia Procedures

Inguinal, Femoral and Umbilical Hernia Procedures – APR-DRG code 228

Kidney/Pancreas Transplant

Kidney/Pancreas Transplant – APR-DRG codes 6 and 440

Laparoscopic Gall Bladder Removal

Laparoscopic Gall Bladder Removal – APR-DRG code 263

Liver Transplant

Liver Transplant – APR-DRG code 1

Major Small and Large Bowel Procedures

Major Small and Large Bowel Procedures – APR-DRG code 221

Major Stomach, Esophageal and Duodenal Procedures

Major Stomach, Esophageal and Duodenal Procedures – APR-DRG code 220

Minor Small and Large Bowel Procedures

Minor Small and Large Bowel Procedures – APR-DRG code 223

Obesity Procedures

Obesity Procedures – APR-DRG code 403

Peritoneal Adhesiolysis

Peritoneal Adhesiolysis - APR-DRG code 224

Radical Prostatectomy

Radical Prostatectomy – APR-DRG code 480

Thyroid, Parathyroid and Thyroglossal Procedures

Thyroid, Parathyroid and Thyroglossal Procedures – APR-DRG code 404

Transurethral Prostatectomy

Transurethral Prostatectomy – APR-DRG code 482

Urethral and Transurethral Procedures

Urethral and Transurethral Procedures – APR-DRG code 446

Women's Health

Hysterectomies and Other Uterine and Adnexa Procedures

Hysterectomies and Other Uterine and Adnexa Procedures – APR-DRG codes 511, 512, 513 and 519 

Hospital Inpatient Medical Conditions and Procedures - Deliveries and Newborns

Baby with Complications

Baby with Complications – APR-DRG codes 583, 588, 589, 591, 593, 602, 603, 607, 608, 609, 611, 612, 613, 614, 621, 622, 623, 625, 626, 630, 631, 633, 634, 636, 639, 640 (APR-DRG 640 is limited to Severity Levels 2, 3 and 4)

Cesarean Section Delivery

Cesarean Section Delivery – APR-DRG code 540 - The data for cesarean deliveries include all ages.

Normal Baby

Normal Baby – APR-DRG code 640 (limited to Severity Level 1)

Vaginal Delivery

Vaginal Delivery – APR-DRG code 560 - The data for vaginal deliveries include all ages.

Hospital Inpatient Medical Conditions and Procedures - Pediatrics

Appendectomy – Ages 1-17 years

Appendectomy – APR-DRG code 225 (limited to Severity Level 1, minor) – Ages 1-17 years

Asthma – Ages 2-17 years

Asthma –Inclusions:  ICD-9-CM principal diagnosis codes of asthma, 49300, 49301, 49302, 49310, 49311, 49312, 49320, 49321, 49322, 49381, 49382, 49390, 49391, and 49392.  Exclusions:  Excludes those patients with a diagnosis code for cystic fibrosis and anomalies of the respiratory system.  Excludes transfers from other institutions. Excludes cases ages 0-1.  Excludes cases in MDC 14 (obstetrics).  Please refer to PDI 14 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for further information regarding methodology.

Brain Surgery – Ages 0-17 years

Brain Surgery – APR-DRG codes 20, 21, and 22 – Ages 0-17 (excluding birth hospitalizations and newborn transfers less than or equal to 28 days old).

Bronchiolitis and RSV Pneumonia – Ages 0-4 years

Bronchiolitis and RSV Pneumonia – APR-DRG code 138 – Ages 0-4 (excluding birth hospitalizations and newborn transfers less than or equal to 28 days old).

Cancer Care – Ages 0-17 years

Cancer Care – APR-DRG codes 680, 681, 690, 691, 692, 693, 694, and 41 – Ages 0-17 (excluding birth hospitalizations and newborn transfers less than or equal to 28 days old).

Cellulitis – Ages 0-17 years

Cellulitis – APR-DRG code 383 (excluding birth hospitalizations and newborn transfers less than or equal to 28 days old).

Convulsions (Seizures) – Ages 0-4 years and 5-17 years

Convulsions (Seizures) – APR-DRG code 53 – Ages 0-4 (excluding birth hospitalizations and newborn transfers less than or equal to 28 days old) and ages 5-17.

Diabetes – Ages 6-17 years

Diabetes – Inclusions: All non-maternal discharges ages 6 to 17 years with ICD-9-CM principal diagnosis codes for short-term complications (ketoacidosis, hyperosmolarity, coma) including 25010, 25011, 25012, 25013, 25020, 25021, 25022, 25023, 25030, 25031, 25032, and 25033. Exclusions: Excludes transfers from other institutions. Excludes cases in MDC 14 (obstetrics). Please refer to PDI 15 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for further information regarding methodology.

Fever and Infectious Illness – Ages 0-17 years

Fever and Infectious Illness – APR-DRG codes 722, 723, and 113 – Ages 0-17 (excluding birth hospitalizations and newborn transfers less than or equal to 28 days old).

Gastroenteritis – Ages 1 year – 4 years and 5-17 years

Gastroenteritis – Inclusions: All non-maternal discharges ages 1 year-4 years and 5-17 years with ICD-9-CM principal diagnosis code for gastroenteritis or with a secondary diagnosis code of gastroenteritis and a principal diagnosis code of dehydration. ICD-9-CM gastroenteritis diagnosis codes 00861, 00862, 00863, 00864, 00865, 00866, 00867, 00869, 0088, 0090, 0091, 0092, 0093, and 5589. ICD-9-CM dehydration diagnosis codes 27650, 27651, 27652, and 2765. Exclusions: Excludes transfers from other institutions. Exclude those with a diagnosis code of gastrointestinal abnormalities or bacterial gastroenteritis. Excludes ages less than 1 year (or neonates if age in days is missing). Excludes cases in MDC 14 (obstetrics). Please refer to PDI 16 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for further information regarding methodology.

Pneumonia, Other – Ages 2-17 years

Pneumonia, Other – APR 139.  Inclusions:Includes ages 2-17. Exclusions: Excludes transfers from other institutions. Exclude cases in MDC 14 (obstetrics). Excludes those patients with a diagnosis code for cystic fibrosis and anomalies of the respiratory system. Please refer to PDI 14 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for further information regarding methodology.

Sickle Cell Disease – Ages 1-17 years

Sickle Cell Disease – APR-DRG code 662 – Ages 1-17.

Spinal Fusion – Ages 5-17 years

Spinal Fusion – APR-DRG codes 303, 304, and 321 – Ages 5-17 years.

Urinary Tract Infections – Ages 1 year to 17 years

Urinary Tract Infections – Inclusions: All non-maternal discharges ages 1 year to 17 years with ICD-9-CM urinary tract principal diagnosis codes 59010, 59011, 5902, 5903, 59080, 59081, 5909, 5950, 5959, 5990.   Exclusions: : Excludes transfers from other institutions. Exclude those patients with a diagnosis code of kidney/urinary tract disorder and with a diagnosis code of high or intermediate-risk immunocompromised state. Excludes ages less than 1 year (or neonates if age in days is missing). Excludes cases in MDC 14 (obstetrics). Please refer to PDI 18 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for a list of the kidney/urinary disorder diagnosis codes and refer to Appendixes C and D for ICD-9-CM Codes for Immunocompromised States and ICD-9-CM Codes for Intermediate-risk Immunocompromised States and more detailed information regarding methodology.

Viral Meningitis – Ages 0-17 years

Viral Meningitis – APR-DRG code 51 – Ages 0-17 years (excluding birth hospitalizations and newborn transfers less than or equal to 28 days old).

Ambulatory (Outpatient) Surgery Centers

Enhanced Ambulatory Patient Groups (EAPGs) – Explanation of Designation as Levels I-IV

EAPGs simplify ambulatory visits for analysis and reporting. This is achieved by identifying key diagnoses and procedures, both diagnostic and therapeutic, performed during an ambulatory visit. Once identified, these diagnoses and procedures are used to classify outpatient visits into categories, called EAPGs, that are both clinically and financial meaningful.

Once the EAPGs are assigned, a second step is taken that assigns a level of complexity to each respective EAPG. Levels I through IV may be assigned to each EAPG. The complexity of an EAPG is defined by the following criteria: clinical similarity within an EAPG, the type (e.g. incision vs excision) of procedures in a particular EAPG, the amount of resources needed for the procedures in an EAPG, and the likelihood that other ancillaries (e.g. diagnostic vs therapeutic procedures involving different types of surgical and other types of surgical pathology) will be performed for the procedure in that EAPG.

Levels of complexity are characterized as follows:

Level I	–	Short treatment time in the operating room. Few laboratory tests or radiology procedures ordered. Few expensive disposable devices used, if any.
Level II	–	Laboratory tests and radiology procedures typically ordered as part of procedure. Disposable devices may consume significant resources. Increased length of time in the operating room.
Level III	–	Laboratory tests and radiology procedures ordered as part of a procedure. Disposable devices consume significant resources. Longer stay in the operating room than levels I and II.
Level IV	–	Procedure of major complexity. Treatment and resources used are extensive. Thus, Level IV EAPGs are frequently performed in an inpatient setting, not in an outpatient setting.

Ambulatory (Outpatient) Surgery Centers Procedures/Surgeries -- Adults

Bones and Joints

Arthroscopy, Level I – EAPG 37

Arthroscopy, Level II – EAPG 38

Bunion Procedures – EAPG 45

Open or Percutaneous Treatment of Fractures – EAPG 43

Digestive System

Colonoscopy, Therapeutic – EAPG 137

Endoscopy of the Lower Airway – EAPG 64

Endoscopy of the Upper Airway, Level I – EAPG 62

Endoscopy of the Upper Airway, Level II – EAPG 63

Hernia Repair, Level I – EAPG 139

Hernia Repair, Level II – EAPG 140

Lower Gastrointestinal Endoscopy, Diagnostic – EAPG 136

Upper Gastrointestinal (GI) Endoscopy or Intubation, Diagnostic – EAPG 134

Upper Gastrointestinal (GI) Endoscopy or Intubation, Therapeutic – EAPG 135

Eyes

Cataract Procedures – EAPG 233

Laser Eye Procedures – EAPG 232

Vitrectomy – EAPG 242

General Surgery

Facial and Ear, Nose and Throat Procedures, Level I – EAPG 252

Facial and Ear, Nose and Throat Procedures, Level II – EAPG 253

Facial and Ear, Nose and Throat Procedures, Level III – EAPG 254

Facial and Ear, Nose and Throat Procedures, Level IV – EAPG 255

Tonsil and Adenoid Procedures – EAPG 256

Heart and Circulatory System

Cardiac Catheterization, Diagnostic – EAPG 84

Pacemaker Insertion and Replacement – EAPG 86

Kidneys and Urologic System

Bladder and Kidney Procedures, Level I – EAPG 163

Bladder and Kidney Procedures, Level II – EAPG 164

Bladder and Kidney Procedures, Level III – EAPG 165

Extracorporeal Shock Wave Lithotripsy – EAPG 160

Skin

Excision and Biopsy of Skin and Soft Tissue, Level I – EAPG 9

Excision and Biopsy of Skin and Soft Tissue, Level II – EAPG 10

Excision and Biopsy of Skin and Soft Tissue, Level III – EAPG 11

Skin Debridement and Destruction, Level I – EAPG 6

Skin Debridement and Destruction, Level II – EAPG 7

Skin Debridement and Destruction, Level III – EAPG 8

Women’s Health

Breast Procedure, Level I – EAPG 20

Breast Procedure, Level II – EAPG 21

Breast Procedure, Level III – EAPG 22

Hysteroscopy – EAPG 200

Ambulatory (Outpatient) Surgery Centers Procedures/Surgeries -- Pediatrics

Bones and Joints

Arthroscopy, Level I – EAPG 37

Arthroscopy, Level II – EAPG 38

Open or Percutaneous Treatment of Fractures – EAPG 43

Digestive System

Endoscopy of the Lower Airway – EAPG 64

Endoscopy of the Upper Airway, Level I – EAPG 62

Endoscopy of the Upper Airway, Level II – EAPG 63

Hernia Repair, Level I – EAPG 139

Hernia Repair, Level II – EAPG 140

Lower Gastrointestinal (GI) Endoscopy, Diagnostic – EAPG 136

Upper Gastrointestinal (GI) Endoscopy or Intubation, Diagnostic – EAPG 134

Upper Gastrointestinal (GI) Endoscopy or Intubation, Therapeutic – EAPG 135

Eyes

Strabismus (Repair of Cross-Eyed) and Muscle Eye Procedures – EAPG 239

General Surgery

Circumcision – EAPG 181

Facial and Ear, Nose and Throat Procedures, Level I – EAPG 252

Facial and Ear, Nose and Throat Procedures, Level II – EAPG 253

Facial and Ear, Nose and Throat Procedures, Level III – EAPG 254

Facial and Ear, Nose and Throat Procedures, Level IV – EAPG 255

Tonsil and Adenoid Procedures – EAPG 256

Inpatient Mortality Indicators

The Agency for Healthcare Research and Quality (AHRQ) software (Version 3.2) was used in calculating the Inpatient Mortality Indicators and Patient Safety Indicators.  This includes a 95% confidence interval for all statistical significance determinations.  If a hospital had fewer than 30 cases, the results were redacted.

Confidence Intervals are used to identify which hospitals had significantly more or fewer deaths than expected given the risk factors of their patients. The confidence interval identifies the range in which the risk-adjusted mortality rate may fall. Hospitals with significantly higher rates than expected after adjusting for risk are those where the confidence interval range falls entirely above the statewide risk adjusted mortality rate. Hospitals with significantly lower rates than expected given the severity of illness of their patients before surgery have the entire confidence interval range entirely below the statewide risk adjusted mortality rate. The more cases a provider performs, the narrower their confidence interval will be. This is because as a provider performs more cases, the likelihood of chance variation in the risk adjusted mortality rate decreases.

For more information, visit the Agency for Healthcare Research and Quality website at:  www.qualityindicators.ahrq.gov.

Mortality Inpatient Procedures

Abdominal Aortic Aneurysm Repair (AAA) Mortality - IQI 11

Inclusions: Number of deaths with a code of AAA repair in any procedure field and a diagnosis of AAA in any field divided by discharges, age 18 years or older, with ICD-9 codes of 3834, 3844, 3864 or 3971 in any procedure field and an AAA diagnosis code of 4413 and 4414 in any field. Exclusions:Excludes cases with missing discharge disposition. Exclude cases transferring to another short-term hospital. Excludes cases in MDC 14 (obstetrics) and MDC 15 (newborns and other neonates).

Coronary Artery Bypass Graft (CABG) Mortality - IQI 12

Inclusions: Number of deaths with a code of CABG in any procedure field divided by discharges, age 40 years and older, with ICD-9 codes of 3610 through 3619 in any procedure field. Exclusions: Excludes cases with missing disposition. Excludes cases transferring to another short-term hospital. Excludes cases in MDC 14 (obstetrics) and MDC 15 (newborns and other neonates).

Craniotomy Mortality (Surgical opening of the skull) - IQI 13

Inclusions: Number of deaths with DRG code for craniotomy (DRG 001, 002, 528, 529, 530, and 543) divided by all discharges, age 18 years and older with DRG code for craniotomy (DRG 001, 002, 528, 529, 530, and 543). Exclusions:Excludes cases with a principal diagnosis of head trauma. Excludes cases missing discharge disposition. Excludes cases transferring to another short-term hospital. Please refer to IQI 13 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for the detailed list of the head trauma diagnosis codes and more detailed information regarding methodology.

Esophageal Resection Mortality (Surgical Removal of the Throat) - IQI 8

Inclusions: Number of deaths with a code of esophageal resection in any procedure field and a diagnosis code of esophageal cancer in any field divided by discharges, age 18 years and older, with ICD-9 procedure codes of 424 -4269 in any field and a ICD-9 diagnosis code of 1500, 1501, 1502, 1503, 1504, 1505, 1508 or 1509 for esophageal cancer in any field. Exclusions:Excludes cases with missing discharge disposition. Excludes cases transferring to another short-term hospital. Excludes cases in MDC 14 (obstetrics) and MDC 15 (newborns and other neonates).

Hip Replacement Mortality - IQI 14

Inclusions: Number of deaths with a procedure code of partial or full hip replacement in any field divided by all discharges, age 18 years and older, with a procedure code of partial or full hip replacement in any field. Include only discharges with uncomplicated cases: diagnosis codes for osteoarthrosis of hip in any field. Exclusions: Excludes cases with missing discharge disposition. Excludes cases transferring to another short-term hospital. Exclude cases in MDC 14 (obstetrics) and MDC 15 (newborns and other neonates). Please refer to IQI 14 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for the list of ICD-9 hip replacement procedure and osteoarthrosis diagnosis codes and more detailed information regarding methodology.

Pancreatic Resection Mortality (Surgical Removal of the Pancreas) - IQI 9

Inclusions: Number of deaths with a code of pancreatic resection in any procedure field and a diagnosis code of pancreatic cancer in any field divided by discharges, age 18 and older, with ICD-9 codes of 526 or 527 in any procedure field and a diagnosis code of 1520, 1561, 1562, 1570, 1571, 1572, 1573, 1574, 1578 and 1579 for pancreatic cancer in any field. Exclusions:Excludes cases with missing discharge disposition. Excludes cases transferring to another short-term hospital. Excludes cases in MDC 14 (obstetrics) and MDC 15 (newborns and other neonates).

Mortality Inpatient Conditions

Acute Myocardial Infarction (Heart Attack) - IQI 15

Inclusions: Number of deaths with a principal diagnosis code of AMI ICD-9 codes 41001, 41011, 41021, 41031, 41041, 41051, 41061, 41071, 41081, or 41091 divided by all discharges, age 18 years and older, with a principal diagnosis code of AMI ICD-9 codes 41001, 41011, 41021, 41031, 41041, 41051, 41061, 41071, 41081, or 41091. Exclusions: Excludes cases where transferred to another short-term hospital. Excludes cases with missing discharge disposition.

Acute Myocardial Infarction (Heart Attack), Without Transfer Cases - IQI 32

Inclusions: Number of deaths with a principal diagnosis code of AMI ICD-9 codes 41001, 41011, 41021, 41031, 41041, 41051, 41061, 41071, 41081, or 41091.divided by all discharges, age 18 and older, with a principal diagnosis code of AMI. Exclusions: Excludes cases where transferred to or from another short-term hospital. Excludes missing admission source and missing discharge disposition.

Acute Stroke Mortality - IQI 17

Inclusions: Number of deaths with a principal diagnosis code for stroke 430, 431, 4320, 4321, 4329, 43301, 43311, 43321, 43331, 43381, 43391, 43401, 43411, 43491, or 436 divided by all discharges, age 18 and older, with a principal diagnosis code of stroke 430, 431, 4320, 4321, 4329, 43301, 43311, 43321, 43331, 43381, 43391, 43401, 43411, 43491 or 436. Exclusions: Excludes cases transferring to another short-term hospital. Exclude cases in MDC 14 (obstetrics) and MDC 15 (newborns and other neonates). Excludes cases with missing discharge disposition.

Congestive Heart Failure (CHF) Mortality - IQI 16

Inclusions: Number of deaths with a principal diagnosis code of CHF divided by all discharges, ages 18 years and older, with principal diagnosis of CHF. Exclusions:Excludes cases with missing discharge disposition. Exclude cases transferring to another short-term hospital. Excludes cases in MDC 14 (obstetrics) and MDC 15 (newborns and other neonates). Please refer to IQI 16 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for the list of ICD-9 CHF diagnosis codes and more detailed information regarding methodology.

Gastrointestinal (GI) Hemorrhage Mortality - IQI 18

Inclusions: Number of deaths with a principal diagnosis code of gastrointestinal hemorrhage divided by all discharges with principal diagnosis code for gastrointestinal hemorrhage. Include ages 18 years and older. Exclusions:Excludes cases transferring to another short-term hospital. Excludes cases in MDC 14 and MDC 15. Excludes cases with missing discharge disposition. Please refer to IQI 18 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for the list of ICD-9 gastrointestinal hemorrhage diagnosis codes and more detailed information regarding methodology.

Hip Fracture Mortality - IQI 19

Inclusions: Number of deaths with a principal diagnosis code of hip fracture divided by all discharges, age 18 and older, with a principal diagnosis code for hip fracture. Exclusions: Excludes cases transferring to another short-term hospital. Excludes cases in MDC 14 and MDC 15. Excludes cases with missing discharge disposition. Please refer to IQI 19 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for the list of ICD-9 hip fracture diagnosis codes and more detailed information regarding methodology.

Pneumonia Mortality - IQI 20

Inclusions: Number of deaths with a principal diagnosis code of pneumonia divided by all discharges, age 18 years and older, with principal diagnosis code of pneumonia. Exclusions: Excludes cases transferring to another short-term hospital. Exclude cases in MDC 14 and MDC 15. Excludes cases with missing discharge disposition. Please refer to IQI 20 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for the list of ICD-9 pneumonia diagnosis codes and more detailed information regarding methodology.

Patient Safety Indicators - Complication and Infection Including Complication Index

The Agency for Healthcare Research and Quality (AHRQ) software (Version 3.2) was used in calculating the Inpatient Mortality Indicators and Patient Safety Indicators.  This includes a 95% confidence interval for all statistical significance determinations.  If a hospital had fewer than 30 cases, the results were redacted.

Confidence Intervals are used to identify which hospitals had significantly more or fewer complications than expected given the risk factors of their patients.  The confidence interval identifies the range in which the risk-adjusted rate may fall.  Hospitals with significantly higher rates than expected after adjusting for risk are those where the confidence interval range falls entirely above the statewide risk adjusted complication rate.  Hospitals with significantly lower rates than expected given the severity of illness of their patients before surgery have the entire confidence interval range entirely below the statewide risk adjusted complication rate.  The more cases a provider performs, the narrower their confidence interval will be.  This is because as a provider performs more cases, the likelihood of chance variation in the risk adjusted complication rate decreases.  This methodology incorporates the Present on Admission (POA) indicator, when appropriate.

For more information, visit the Agency for Healthcare Research and Quality website at:  www.qualityindicators.ahrq.gov

Decubitus Ulcer - PSI 3

Inclusions: Cases of decubitus ulcer per 1,000 discharges. Includes discharges with ICD-9 code of decubitus ulcer in any secondary diagnosis field. Includes all medical and surgical discharges, ages 18 years and older defined by specific DRGs.

Exclusions: Cases with a length of stay between 0-4 days. Excludes cases with preexisting condition of decubitus ulcer (primary diagnosis or secondary diagnosis present on admission, if known). Excludes cases in MDC 9 and MDC 14. Exclude cases with any diagnosis of hemiplegia, paraplegia, or quadriplegia. Exclude cases with an ICD-9-CM code of spina bifidia or anoxic brain damage. Excludes cases with ICD-9-CM procedure code for debridement or pedicle graft before or on the same day as the major operating room procedure (surgical cases only). Excludes patients admitted from a long-term care facility or transferred from an acute care facility.

Reference: For more detailed information regarding methodology please refer to PSI 3 (AHRQ Version 3.1) at www.qualityindicators.ahrq.gov for the detailed list of ICD-9-CM decubitus ulcer, hemiplegia, paraplegia, quadriplegia, spina bifidia, and anoxic brain damage diagnosis codes. Refer to the list of ICD-9-CM procedure codes for debridement or pedicle graft. Refer to Appendixes A, B, and F for applicable operating room procedure codes, medical and surgical DRGs, respectively.

Iatrogenic Pneumothorax - PSI 6

Inclusions: Cases of iatrogenic pneumothorax per 1,000 discharges. Include discharges with ICD-9-CM code of 512.1 in any secondary diagnosis field. Includes all medical and surgical discharges, ages 18 years and older defined by specific DRGs.

Exclusions: Cases with ICD-9-CM code of 512.1 in the principal diagnosis field or secondary diagnosis present on admission, if known. Exclude cases in MDC 14 (obstetrics). Excludes patients with diagnosis code of chest trauma or pleural effusion. Excludes patients with any procedure code of diaphragmatic surgery repair, thoracic surgery, lung or pleural biopsy, or patients assigned to cardiac surgery DRGs.

Reference: For more detailed information regarding methodology please refer to PSI 6 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for the list of ICD-9-CM chest trauma and pleural effusion diagnosis codes, thoracic surgery, local excision or destruction of lesion or tissue lung, repair and plastic operation on lung and bronchus, lung transplant, diagnostic procedures on chest wall, pleura, mediastinum, and diaphragm, repair of chest wall, operations on diaphragm, operations on thoracic duct, esophagotomy, excision of esophagus, intrathoracic anastomosis of exophagus, antesternal anastomosis, other repair of esophagus, lung or pleural biopsy procedure codes and cardiac surgery DRGs.

Infections Due to Medical Care - PSI 7

Inclusions: Cases selected infections due to medical care, secondary diagnosis per 1,000 discharges. Includes discharges with ICD-9-CM codes 999.3 or 996.62 in any secondary diagnosis field. Includes discharges for all medical and surgical discharges, ages 18 years and older or MDC 14 (obstetrics), defined by specific DRGs.

Exclusions: Excludes cases with ICD-9-CM code of 999.3 or 996.62 in the principal or secondary diagnosis field present on admission, if known. Excludes cases with length of stay between 0-1 days. Excludes cases with any code of immunocompromised state or cancer or with cancer DRG.

Reference: For more detailed information regarding methodology please refer to PSI 7 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for the list of applicable codes and/ or DRGs refer to Appendixes B, F, D, E and Q for applicable surgical discharge DRGs, medical discharge DRGs, ICD-9-CM codes for immunocompromised states, cancer codes and cancer DRGs, respectively.

Postoperative Hip Fracture - PSI 8

Inclusions: Cases of hip fracture per 1,000 surgical discharges. Includes cases of any secondary ICD-9-CM codes for hip fracture. Includes all surgical discharges age 18 and older defined by specific DRGs and an ICD-9-CM code for an operating room procedure.

Exclusions: Excludes cases with ICD-9-CM code for hip fracture in the principal diagnosis field or secondary diagnosis present on admission, if known. Excludes cases where the only operating room procedure is hip fracture repair. Excludes cases where a procedure for hip fracture repair occurs before or on the same day as the first operating room procedure. Excludes cases in MDC 8 (diseases and disorders of the musculoskeletal system and connective tissue). Excludes cases with principal diagnosis (or secondary diagnosis present on admission, if known) of seizure, syncope, stroke, coma, cardiac arrest, poisoning, trauma, delirium and other psychoses, or anoxic brain injury. Excludes cases with any diagnosis of metastatic cancer, lymphoid malignancy or bone malignancy, or self-inflicted injury. Exclude cases in MDC 14 (obstetrics).

Reference: For more detailed information regarding methodology please refer to PSI 8 (AHRQ Version 3.1) at www.qualityindicators.ahrq.gov for the detailed list of hip fracture repair procedure codes, hip fracture, seizure, syncope, stroke, occlusion and stenosis of precerebtal arteries, occlusion of cerebral arteries, coma, cardiac arrest, poisoning, delirium and other psychoses, anoxic brain injury, metastatic cancer, lymphoid malignancy, bone malignancy diagnosis codes. Also refer to Appendixes A, B, C, J and L for applicable operating room procedure codes, surgical discharge DRGs, ICD-9-CM trauma diagnosis codes, trauma DRGs, and self-inflicted injury diagnosis codes, respectively.

Postoperative Pulmonary Embolism or Deep Vein Thrombosis - PSI 12

Inclusions: Cases of secondary deep vein thrombosis or pulmonary embolism diagnosis per 1,000 surgical discharges. Includes discharges with an ICD-9-CM code for deep vein thrombosis or pulmonary embolism in any secondary diagnosis field. Includes all surgical discharges age 18 and older defined by specific DRGs and an ICD-9-CM code for an operating room procedure.

Exclusions: Excludes cases with preexisting (principal or secondary diagnosis present on admission, if known) deep vein thrombosis or pulmonary embolism. Excludes cases where a procedure for interruption of vena cava is the only operating room procedure. Excludes cases where a procedure for interruption of vena cava occurs before or on the same day as the first operating room procedure. Excludes cases in MDC 14 (obstetrics).

Reference: For more detailed information regarding methodology please refer to PSI 12 (AHRQ Version 3.1) at www.qualityindicators.ahrq.gov for the detailed list of interruption of vena cava diagnosis codes. Also refer to Appendixes A, B, C, and K for applicable operating room procedure codes, surgical discharge DRGs, ICD-9-CM trauma diagnosis codes, pulmonary embolism/deep vein thrombosis diagnosis codes, respectively.

Postoperative Sepsis - PSI 13

Inclusions: Cases of secondary sepsis diagnosis per 1,000. Include elective surgery discharges with ICD-9-CM code for sepsis in any secondary diagnosis field. Include all elective surgical discharges age 18 and older defined by specific DRGs and an ICD-9-CM code for an operating room procedure.

Exclusions: Excludes cases with preexisting (principal or secondary diagnosis present on admission, if known) sepsis or infection. Excludes cases with any code for immunocompromised state of cancer. Excludes cases in MDC 14 (obstetrics). Excludes cases with length of stay 0-3 days.

Reference: For more detailed information regarding methodology please refer to PSI 13 (AHRQ Version 3.2) at www.qualityindicators.ahrq.gov for the detailed list diagnosis codes and DRGs refer to Appendixes O,P, D, E, and Q for applicable sepsis diagnosis codes, infection diagnosis codes and DRGS, ICD-9-CM codes for immunocompromised states, cancer codes and cancer DRGs, respectively.