Patients classification System

tools for
Cost management

tools for
Quality management

tools for
HOSPITAL PLANNING

4  Why to choose US

4  implementation

4  ANECDOTE

4  contact

4  Logic

4  diagnoses

4  procedures

4  inpatients

4  outpatients

4  insurance

4  readmissions

4  reoperations

4  complications

4  deaths

4  length of stay

4  day surgery

4  unjustified stays

OUTPUT FILES DESCRIPTION

Overview

All indicators are provided for hospital acute somatic care. Stays in geriatrics, rehabilitation units, psychiatrics units (M500, M900, M950, M990) are not taken into account.

Global results are provided separately for each hospital and hospital site in Excel workbooks specific to each indicator (readmission.xls, cost.xls, etc.).

Detailed results are provided in separate text files, corresponding to the eligible population of specific indicators:

- Eligible_discharges.txt for READMISSIONS (excluding transferred and dead patients, healthy newborns, foreigners, candidates for day surgery);
- Eligible_operations.txt for
REOPERATIONS (each operation day with at least one therapeutic surgical procedure);
- Eligible_surgery.txt for candidates to one
DAY SURGERY (at least a surgical intervention, not transferred or discharged alive, programmed);
- Eligible_death.txt for premature
DEATH (patients not considered as at the end of their life);
- Eligible_cases.txt for
UNJUSTIFIED STAYS (all discharges are eligible, except those with only one day duration;
- Analysis.txt for
length of stay, hospital cost and complications (all discharges are eligible).

To facilitate further analyses, SQLape® tool generate four data files:

- Cases.txt, with all non medical variables included in SQLape_input.txt file
- Health.txt: case identifier, health problem (ICD-10) and rank
- Procedure.txt: case, procedure, date of operation
- Categories.txt: case, SQLape category.

Notation

A systematic notation is used for all results, with indices describing observed value (index 1) and expected values (index 0, 0min and 0max giving the 95% confidence intervals). The two letters before indices correspond to abbreviations of each indicator:

AR

Potentially avoidable readmissions
- ARi for internal readmissions
- ARe for external readmissions

BE

Potential of beds reduction

CO

Hospital costs

CP

Iatrogenic complications

DS

One day surgery

LS

Length of stay

PD

Premature death

RO

Potentially avoidable reoperations

UJ

Unjustified stays

For instance, LS1 is the observed length of stay and RO0min is the minimal expected rate of potentially avoidable reoperations.

For each indicator, the SQLape® tool computes the ratio between observed and expected values (rate ratio, ratio of costs, ratio of length of stay). For instance, RAR = R1/R0

Performance is measured by ratios, with good results if ratios are low (observed < expected values) and bad results corresponding to high ratios. A ratio of 1.2 means that observed rate is 20% greater than expected, for instance.

Expected values are provided with 95% confidence intervals, assessing if they differ significantly from observed rates:

A  observed rate < minimal expected rate (significantly lower than expected)
B  minimal expected rate < observed rate < maximal expected rate
C  observed rate > maximal expected rate (significantly higher than expected)

Some additional information is provided in global results (per hospital and site)

c   number of cases (numerator)

e   elective population size (denominator)

n   number of stays provided in SQLape_input.txt file, corresponding to acute somatic care

q   quality of data, measured specifically for each indicator (see below)

s   sum

d   difference

p   potential reduction (proportion of potential improvement)

Some additional information is provided in detailed results (per stay or operation):

Dates:  admission, discharge, readmission, reoperation dates for instance (01.01.2200 or 31.12.2999 correspond to unspecified dates)
Identifiers: #Hospital, #Case, #Readmission, etc. (# designing identifiers)
Groups: Risk groups
Etc.

Context variables

To assess length of stays, hospital costs and beds, we compute the variable “analysis” describing the context of hospital stays:

A. Back home, not followed by a potentially avoidable readmission (if not classified as B-F)
B. Back home, followed by a potentially avoidable readmission (if not classified as C-F)
C. Transfer at discharge or death
D. Nursing home placement (if not transferred)
E. Candidates for one day surgery
F. Unjustified stay

New case definition (Switzerland)

When cases include several hospital stays (new Swiss definition of the case, introduced in 2012), each stay is newly built with admission and discharge dates. The case identifier is extended with the rank of the stay (for instance: 19222110_1, 19222110_2, 19222110_3 if there are two interruptions). Diagnoses are linked to each stay, but procedures are allocated to corresponding stays knowing their dates.

GLOBAL RESULTS

Synthesis (Synthesis.xls)

Variables                                     Description

For each hospital and site:

A                                                   Indicator
                                                     - Length of stay
                                                     - Hospital cost

                                                     - Potentially avoidable readmission
                                                     - Potentially avoidable reoperation
                                                     - Premature death
                                                     - Iatrogenic complication
Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

n                                                   Number of stays in the SQLape_input.txt file

q                                                   Quality of data

N                                                  Numerator of the indicator (cases, hospital days or Swiss francs)

D                                                   Denominator of the indicator (eligible population)

V1                                                 Observed value (rate, length, cost) = N/D

V0                                                 Expected value (rate, length, cost)
V0min                                             Minimal expected rate

V0max                                            Maximal expected rate

R                                                   Rate, length or cost ratio (observed/expected values)

V                                                   Result :
                                                     A   observed value < minimal expected value (good)
                                                     B   minimal expected value < observed value < maximal expected value
                                                     C   observed value > maximal expected value (too high)

GLOBAL RESULTS

Length of stay (Length.xls)

Variables                                     Description Variables            Description

H                                                   Hospital identifier

Site                                               Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

n                                                   number of stays in the SQLape_input.txt file

qLS                                                quality of data for length of stay indicator

cLS                                                 number of hospital days (including admission and discharge days, except for stays with interruptions
                                                     (see “new case definition”, above)

eLS                                                number of discharges

LS1                                                observed length of stay (cLS/eLS)

LS0                                                expected rate
LS0min                                           minimal expected rate

LS0max                                           maximal expected rate

RLS                                                length ratio (LS1/LS0)

VLS                                                Result :
                                                     A   observed rate < minimal expected rate (good)
                                                     B   minimal expected rate < observed rate < maximal expected rate
                                                     C   observed rate > maximal expected rate (too high)

GLOBAL RESULTS

Hospital cost (Cost.xls)

 

Variables                                     Description

H                                                   Hospital identifier

Site                                               Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

n                                                   number of stays in the SQLape_input.txt file

qCO                                                quality of data for cost indicator

cCO                                                amount of hospital resources (Swiss francs)

eCO                                                number of discharges

CO1                                              observed cost (cCO/eCO)

CO0                                              expected cost
CO0min                                          minimal expected cost

CO0max                                         maximal expected cost

RCO                                               cost ratio (CO1/CO0)

CO0CH                                           Swiss reference rate

COa                                              Adjusted reoperation rate (CO0CH * RCO)

VCO                                               Result :
                                                     A   observed rate < minimal expected rate (good)
                                                     B   minimal expected rate < observed rate < maximal expected rate
                                                     C   observed rate > maximal expected rate (too high)

GLOBAL RESULTS

Potentially avoidable readmissions (Readmission.xls)

 

Variables                                     Description

H                                                   Hospital idenfier

Site                                               Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

n                                                   number of stays in the SQLape_input.txt file

qAR                                                quality of data for readmission indicator

cAR                                                number of potentially avoidable readmissions (internal and external)

eAR                                                number of eligible discharges

AR1                                               observed rate of potentially avoidable readmissions (=AR1i + AR1e=cAR/eAR)

AR1i                                              internal observed rate (in the same hospital readmissions)

AR1e                                             external observed rate (in other hospital readmissions)

AR0                                               expected rate (internal and external)
AR0min                                          minimal expected rate

AR0max                                          maximal expected rate

RAR                                               rate ratio (AR1/AR0)

vAR                                                Result :
                                                     A   observed rate < minimal expected rate (good)
                                                     B   minimal expected rate < observed rate < maximal expected rate
                                                     C   observed rate > maximal expected rate (too high)

GLOBAL RESULTS

Potentially avoidable reoperations (Reoperation.xls)

 

Variables                                     Description

H                                                   Hospital identifier

Site                                               Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

n                                                   number of stays in the SQLape_input.txt file

qRO                                               quality of data for reoperation indicator

cRO                                                number of potentially avoidable reoperations

eRO                                               number of eligible operations

RO1                                              observed rate of potentially avoidable reoperations (cRO/eRO)

RO0                                              expected rate
RO0min                                          minimal expected rate

RO0max                                         maximal expected rate

RRO                                               rate ratio (RO1/RO0)

VRO                                               Result :
                                                     A   observed rate < minimal expected rate (good)
                                                     B   minimal expected rate < observed rate < maximal expected rate
                                                     C   observed rate > maximal expected rate (too high)

GLOBAL RESULTS

Premature death (Death.xls)

 

Variables                                     Description

H                                                   Hospital identifier

Site                                               Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

n                                                   number of stays in the SQLape_input.txt file

qPD                                                quality of data for premature death indicator

cPD                                                number of premature deaths

ePD                                                number of discharges of patients not at the end of their life

PD1                                               observed rate of premature deaths (cPD/ePD)

PD0                                               expected rate
PD0min                                          minimal expected rate

PD0max                                          maximal expected rate

RPD                                                rate ratio (PD1/PD0)

VPD                                                Result :
                                                     A   observed rate < minimal expected rate (good)
                                                     B   minimal expected rate < observed rate < maximal expected rate
                                                     C   observed rate > maximal expected rate (too high)

GLOBAL RESULTS

Iatragenic complications (Complication.xls)

Variables                                     Description

H                                                   Hospital identifier

Site                                               Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

n                                                   number of stays in the SQLape_input.txt file

qCP                                                quality of data for complication indicator

cCP                                                number of iatrogenic complications

eCP                                                number of discharges of patients

CP1                                               observed rate of iatrogenic complications (cCP/eCP)

CP0                                               expected rate

CP0min                                          minimal expected rate

CP0max                                          maximal expected rate

RCP                                                rate ratio (CP1/CP0)

VCP                                                Result :

                                                     A   observed rate < minimal expected rate (good)

                                                     B   minimal expected rate < observed rate < maximal expected rate

                                                     C   observed rate > maximal expected rate (too high)

GLOBAL RESULTS

Day surgery (Daysurgery.xls)

Variables                                    

H                                                   Hospital identifier

L                                                   Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

n                                                   number of stays in the SQLape_input.txt file

qDS                                                quality of data for day surgery (same criteria than for length of stay)

cDS                                                number of candidates for one day surgery

eDS                                                number of eligible discharges

DS1                                               observed rate of candidates for one day surgery (cDS/eDS)

DS0                                               expected rate
DS0min                                          minimal expected rate

DS0max                                          maximal expected rate

RDS                                                rate ratio (DS1/DS0)

VDS                                                Result :
                                                     A   observed rate < minimal expected rate (good)
                                                     B   minimal expected rate < observed rate < maximal expected rate
                                                     C   observed rate > maximal expected rate (too high)

GLOBAL RESULTS

Beds reduction (Beds.xls)

Variables                                     Description

H                                                   Hospital identifier

Site                                               Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

N1                                                 observed number of stays

N0                                                 expected number of stays (if no more than 15% of candidates for one day surgery
                                                     and no more than 5% of unjustified hospitalizations)

LS1                                                observed length of stay

LS0                                                expected length of stay
dCP                                                Excess of complication (=CP1-CP0), if CP1>CP0, else if = 0

dLS                                                Excess of length of stay dLS = (LS1C – LS0C) - (LS1Æ – LS0Æ),
                                                     more details: 4 COMPLICATIONS-INTERPRETATION

pN                                                 reduction potential related to case numbers
                                                     = (N1-N0) [min(LS0;LS1)-1]/
SLS1 for candidates for one day surgery if N1>N0
                                                     = (N1-N0) min(LS0;LS1)/
SLS1 for unjustified stays if N1>N0
                                                                      
= 0 in other cases

pCP                                                reduction potential related to complications
                                                     = N1 dCP dLS /
SLS1

pLS                                                reduction potential related to length of stay
                                                     =  N1 (LS1-LS0) /
SLS1 - pCP   if > 0, else if = 0

BE1                                               observed number of beds (=SLS1 / (365 *0.85)

BE0                                               expected number of beds (=SLS1 (1-pN-PCP-PLS) / (365 *0.85)

DBE                                               potential reduction of the number of beds (B1 – B0)

 

General explanations

There are three ways to reduce the number of hospital days and therefore hospital beds: to avoid unnecessary hospitalizations, to lower the incidence of complications and to reduce length of stay.

Avoiding unnecessary hospitalizations (proportion pN)

It is not wise to eliminate all candidates for one day surgery, because some of them are justified, for instance because patients live alone, too far from hospital to come back if a complication occur or for other reasons. We consider here that a lower threshold of 15% is normal, but that supernumerary stays could probably be treated in less than 24 hours.

Similarly, we consider that a threshold of 5% of unjustified stays is normal, because some patients need to be monitored to exclude severe morbidities or risk of complications. But, many of such situations might also be managed by ambulatory care and the supernumerary stays might provide hospital days savings.

The impact of avoiding unnecessary hospitalizations is estimated by the difference between observed and expected numbers of stays (N1-N0), weighted by optimal length of stay (the minimum between observed and expected values, min[LS0;LS1]). One day was considered appropriate for candidates for one day surgery. This potential savings (pN) is expressed in proportion of actual number of hospital days (sum of observed hospital days LS1).

 

Lowering complications rates (proportion pCP)

Expected lengths of stay are computed considering all illnesses of patients, inclusive complications. This is justified by the fact that not all complications can be avoided even in the best hospitals. But if there is an excess of complications rates (dCP), there is a corresponding potential of reduction, estimated by the observed excess of length due to complications (dLS).

Reducing length of stay (proportion pLS)

The potential reduction is computed by the difference of lengths of stay (observed LS1 – expected LS0) weighted by the observed number of cases (N1) and expressed in proportion of the total number of hospital days (SLS1). The part of excessive length due to complication (pCP, see above) is not considered here.

Estimation of the impact on the number of beds

The number of beds is estimated with a standard bed occupancy rate of 85% and a full utilization during the all years (365 days).

DETAILED RESULTS

Length of stay, hospital cost and complications (Analysis.txt)

Variables                                     Description

#Case                                          Hospital stay identifier

Analysis                                       A. Back home, without readmission
                                                     B. Back home, with readmission
                                                     C. Transfer or death

                                                     D. Nursing home placement (Stay before <>3 and <>4, Stay after =2 or 3)

                                                     E. Day surgery

                                                     F. Unjustified stay

#Hospital                                    Hospital identifier

#Site                                            Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

#Patient                                      Patient identifier

#Case                                          Hospital stay identifier

DateIndex                                   Date of index operation (each day = another eligible operation)

Age                                              Age at admission

Gender                                        1 = male, 2 = female

Entry                                            0 = birth, 1 = transfer (Stay before = 5 or 6), 2 = other
End                                               0 = death, 1 = transfer (Stay after = 4, 5 or 6), 2 = other

Specialty                                     4 SPECIALTY (.pdf)
                                                    
4 SPECIALTY (.xls)
                                                    
4 SPECIALTY (.txt)

Mission                                       New variable added for hospital planning purpose (more details will be given soon on the website)

Category                                     Main SQLape® category

CP1                                               Observed rate of complications (1 = yes, 0 = no)
CP0                                               Expected rate of complications

CP0min                                          Minimal expected rate of complications (idem)

CP0max                                          Maximum expected of complications (idem)

LS1                                                Observed length of stay
LS0                                                Expected length of stay

LS0min                                           Minimal expected length of stay (idem)

LS0max                                           Maximum expected length of stay (idem)

LS0_CP                                           Expected length of stay for observed complications

CO1                                              Observed hospital cost (1 = yes, 0 = no)
CO0                                              Expected hospital cost

CO0min                                          Minimal expected hospital cost (idem)

CO0max                                        Maximum expected hospital cost (idem)

DETAILED RESULTS

Readmissions (Eligible_discharges.txt)

Variables                                     Description

#Hospital                                    Hospital identifier

#Site                                            Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

#Patient                                      Patient identifier

#Case                                          Index stay identifier (index stay = eligible for a possible readmission)

Age                                              Age at admission

Gender                                        1 = male, 2 = female

Previous                                      Hospitalization during the six months prior to admission date

Programmed                              1=planned, 0=unplanned (corresponding to “admission mode” = 1 or 3 in SQLape_input.txt file)

#Group-AR                                 Clinical groups, used to compute expected rates (labels in Excel table)

AdmissionDate                          Admission date of the index stay (each eligible discharge)

DischargeDate                           Discharge date of the index stay (each eligible discharge)

AR0                                               Expected rate

AR0min                                          Minimal expected rate (idem)

AR0max                                          Maximum expected rate (idem)

AR1                                               Observed rate (internal or external, = 1 if potentially avoidable readmission, 0 if not

ReadmissionDate                      Admission date of the readmission stay (31.12.2999 if no readmission)

ARDelay                                      Admission date of the readmission – Discharge date of the index stay

#Readmission                            Identifier of the readmission

ReadmissionHospital               Identifier of the hospital of readmission

AR1i                                              Observed internal rate (= 1 if potentially avoidable readmission in the same hospital, 0 if not)

DETAILED RESULTS

Reoperations (Eligible_operation.txt)

Variables                                     Description

#Hospital                                    Hospital identifier

#Site                                            Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

#Patient                                      Patient identifier

#Case                                          Hospital stay identifier

DateIndex                                   Date of index operation (each day = another eligible operation)

Age                                              Age at admission

Gender                                        1 = male, 2 = female

Programmed                              Admission mode = 1 or 3

#Group-RO                                 Clinical groups, used to compute expected rates (labels in Excel table)

AdmissionDate                          Admission date of the index stay (each eligible discharge)

DischargeDate                           Discharge date of the index stay (each eligible discharge)

RO0                                              Expected rate

RO0min                                          Minimal expected rate (idem)

RO0max                                         Maximum expected rate (idem)

RO1                                              Observed rate (= 1 if potentially avoidable reoperation,0 if not

ReoperationDate                      Admission date of the reoperation

RODelay                                      Reoperation date – previous operation date

DETAILED RESULTS

Premature death (Eligible_death.txt)

Variables                                     Description

#Case                                          Hospital stay identifier

#Hospital                                    Hospital identifier

#Site                                            Location of the hospital

Year                                             Year (most frequent discharge year in the SQLape_input.txt file)

Specialty                                     4 SPECIALTY (.pdf)
                                                    
4 SPECIALTY (.xls)
                                                    
4 SPECIALTY (.txt)

Complexity                                 3    > 7 SQLape® categories (complications categories excluded)
                                                     2    >3 SQLape® categories (complications categories excluded)

                                                     1    1 SQLape® category (complications categories excluded)

AgeClass                                     Class of age, expressed in years
PD1                                               Observed rate (= 1 if premature death, 0 if not

PD0                                               Expected rate

PD0min                                          Minimal expected rate (idem)

PD0max                                          Maximum expected rate (idem)

DETAILED RESULTS

Candidates for one day surgery (Eligible_surgery.txt)

Variables                                     Description

EligibleDS                                    Hospital stay identifier

#Hospital                                    Hospital identifier

#Site                                            Location of the hospital

DS1                                               Observed rate (= 1 if candidates for one day surgery, 0 if not

DS0                                               Expected rate = 10% of eligible stay with surgery

DS0min                                          idem (no statistical model)

DS0max                                          idem (no statistical model)

DETAILED RESULTS

Unjustified hospitalizations (Eligible_cases.txt)

Variables                                     Description

#Case                                          Hospital stay identifier

#Hospital                                    Hospital identifier

#Site                                            Location of the hospital

UJ1                                               Observed rate (= 1 if candidates for one day surgery, 0 if not)  

UJ0                                               Expected rate = 10% of eligible stay with surgery

UJ0min                                           idem (no statistical model)

UJ0max                                          idem (no statistical model)

© Yves Eggli and SQLape s.à.r.l., 2014. Last update: 29.04.2016