Analysis of Waiting-Time Data in Health Services Research
In health care systems that provide universal access to care, efforts to contain costs for standby hospital capacity usually result in wait lists for surgical procedures. When access to health care is rationed by such wait lists, the length of time that patients are required to wait is usually uncertain. This uncertainty is a natural product of stochastic variation in service time and in the percentage of urgent cases in any queuing system. However, in a queue for elective (nonemergency) procedures, waiting-time uncertainty has many additionalcauses. Forinstance,decisionsofbothpatientsandcareprovidersmayoverrideaqueuediscipline. Alternatively, the lack of a hospital resource, such as beds in the intensive care unit, may change queuing practices in favor of services that would not require the resource. Waiting time is often compared between regions, hospitals, periods, or surgical services to evaluate p- icy and performance. However, surprisingly little attention has been given to the variation in times spent in a single queue. Why some patients wait longer than others remains an important question in health services - search. Itisunclear,forexample, whether timetoservicevariesmorethanwouldbeexpected throughchance alone after differences in clinical condition are taken into account. Another important issue is preferential allocation of hospital resources. It also remains unclear whether patients of low priority are admitted directly as a way to circumvent long wait lists or to substitute for cancellations on the operating room schedule.
What people are saying - Write a review
We haven't found any reviews in the usual places.
Variation and access probabilities
53 What is the probability of undergoing surgery within a certain time?
532 Elective coronary artery bypass grafting
Factors inﬂuencing waiting times
622 Elective coronary artery bypass grafting
63 Does registration period affect waiting times?
64 Does the type of procedure affect waiting times?
65 Does waitlist size at registration affect time to surgery?
192 Truncated samples
195 Competing risks
Waitingtime data used in this book
22 Access to coronary artery bypass grafting surgery
222 Other data sources
224 Patient population
23 Access to elective vascular surgery
233 Priority groups
242 Patient population
Waits and outcomes What should be reported?
322 Proportions and odds Deﬁnition
323 Hazard and rates Deﬁnition
324 Probabilities of access Deﬁnition
325 Cumulative incidence functions Deﬁnition
326 Conditional probability functions Deﬁnition
33 Methods of comparison
334 Comparison of probabilities of access Logrank test
335 Comparison of cumulative incidence functions
336 Comparison of conditional probability functions
34 Regression models
343 Cox regression
344 Poisson loglinear regression
345 Discretetime regression
346 Regression for pseudovalues of cumulative incidence functions
Overview of waiting times and other variables
423 Waitlist size
442 Waiting outcomes
652 Elective coronary artery bypass grafting
Surgery after target access time
73 What is the relation between weekly number of emergency referrals and elective admissions within the target time?
Adverse events while waiting
83 What is the risk of unplanned emergency surgery among patients waiting for surgery?
832 Elective coronary artery bypass grafting
84 What is the relation between length of the wait list at registration for coronary artery bypass grafting and chances of death while on the wait list?
85 What is the relation between length of the wait list at registration for coronary artery bypass grafting and chances of unplanned emergency surgery?
86 What is the risk of death associated with delayed surgical treatment of coronary artery disease?
93 What is the effect of registration period in the presence of delays?
Survival beneﬁt of coronary artery bypass grafting 101 Introduction
A2 Data dictionary for vascular
A3 Data dictionary for cholecystectomy
B12 Preparing data set on access to coronary artery bypass grafting surgery
B13 Preparing data set on access to cholecystectomy surgery
B2 Estimating summary measures
B22 Macro to estimate event rates by group
B3 Creating new variables and reformatting records
B32 DATA step for creating patient by week data for access to surgery
B33 DATA step for creating patient by week data for ontime surgery
B34 DATA step for expansion to pseudovalues data
C2 Estimating the conditional probability function
C3 Comparing conditional probability functions in two groups
Other editions - View all
Analysis of Waiting-Time Data in Health Services Research
Boris Sobolev,Lisa Kuramoto
No preview available - 2007
100 patient-weeks 52 weeks access to surgery admission rate analysis artery bypass grafting batch CABG chi-square chi-square distribution cholecystectomy comorbidity competing event conditional probability confidence interval coronary artery bypass covariates cumulative incidence function data set DATA step delay in scheduling described in Chapter disease elective coronary artery elective surgery elective vascular surgery emergency admission event of interest event rate hazard ratio indicator variables log-rank test logistic regression nonurgent group null hypothesis number of events number of patients odds ratio operating room patients registered peripheral vascular disease Poisson regression preoperative death primary event priority group probability of undergoing procedures proportion of patients pseudovalues registered for elective registration period registration weeks regression model SAS Code SAS Output scheduling delay semiurgent group surgery rate survival analysis Table target access test statistic time-dependent total number treatment undergoing surgery unplanned emergency surgery urgent wait-list week Wald test weekly rate
Page 207 - Yusuf S, Zucker D, Peduzzi P, et al: Effect of coronary artery bypass graft surgery on survival: overview of 10-year results from randomised trials by the Coronary Artery Bypass Graft Surgery Trialists Collaboration.