With the growing reliance on large health care data bases, the need to verify data quality increases as well. Because of the considerable costs involved in checks using primary data collection, a computerized methodology for performing such checks is suggested. The technique seems appropriate for any situation where two data collection systems (i.e. hospital discharge abstracts and physician claims for payment) relate to the same event, such as a patient's hospitalization. After reviewing other approaches, this paper suggests linking physician claims for performing particular surgical procedures with hospital discharge abstracts for the stay in which the surgery took place. Physician and hospital data for adults age 25 and over in Manitoba from 1 April, 1979 to 31 March, 1984 were used to address the questions: 1. How well can the two data sets be linked? 2. Given linkage of the two data sets, how much agreement is there as to procedure and diagnosis? Linkage between hospital and physician data was excellent (over 95%) for 5 out of 11 surgical procedures (hysterectomy, prostatectomy, total hip replacement, coronary artery bypass surgery, and heart valve replacement); there was over 90% perfect agreement for three other procedures (cholecystectomy, cataract surgery and total knee replacement). Problems with matching the Manitoba Health Services Commission tariffs (on physician claims) with ICD-9-CM operation codes (on hospital data) led to only 77% perfect agreement for vascular surgery and 84% for gallbladder and biliary tract operations other than cholecystectomy; over 10% of the cases linked on surgeon and date but not on the designated procedures.(ABSTRACT TRUNCATED AT 250 WORDS)
An overview of the Manitoba study of common surgical procedures is presented. The research is oriented toward describing and explaining the outcomes of nine relatively common procedures, using longitudinal data from the Manitoba Health Services Commission's population registry, medical claims, and physician claims. The research approach recognizes differences among surgical procedures, tailoring the analyses to specific characteristics of a given procedure. At the same time, this article describes the efforts made to achieve economies of scale in organizing the data base and writing the computer programs. The strategy used for assessing surgical risks and benefits is described at some length. Health services utilization before and after surgery is compared across small areas with widely differing surgical rates. Comparisons between surgical and other groups are suggested. The wealth of data permits a number of different types of studies. One study deals with patterns of surgical practice, types of operations performed, and risk characteristics of patients brought to surgery in areas with differing surgical rates. High-risk patients residing in high-rate areas are more likely to be operated upon than their counterparts in low-rate areas. A second study found that hysterectomy is apparently being used in situations where women have high rates of contact with the health care system before surgery; their rates of contact after surgery are almost as high. Ongoing activities in the research project are outlined.
This paper discusses several practical problems in research design: Is it worth doing a relatively "quick and dirty" study or is a more thorough study using all available information necessary? All the desired information may either not be available or be time-consuming to collect. What are the likely biases in going ahead and doing the research with the data base "in hand"? Such issues are important because of the limited resources for technology assessment (in terms of money, number of researchers, and research interest) and the great number of unstudied technologies.
This study concentrates on utilizing registries and assessing their quality for population-based research. A method of successive comparisons is used to develop and update a summary record of coverage (length of time on the registry) and mortality for each individual in the Manitoba Health Services Commission data base. Various ways to ascertain the accuracy of the summary records are discussed. These techniques are validated by efforts to follow over an 8-year period 4,794 individuals interviewed in 1971 as part of ongoing research on the Manitoba elderly. Ninety-seven percent of the total elderly sample (and 99% of those successfully matched with interviewees) were traced over 8 years. Deaths recorded on hospital claims but not on the master registry and possible unrecorded out-of-hospital deaths are outstanding problems with the Manitoba data base. Further checks against 1970-1977 vital statistics information in the Canadian Mortality Data Base will be made.
Research on adverse outcomes following common surgical procedures has suggested the importance of hospital and surgeon variables. Policy directions depend on which factors are important in influencing patient outcomes and what sorts of policies are feasible. Focusing on where a given procedure is performed highlights a concern for centralization; emphasizing who should perform a particular operation implies physician certification. Finally, monitoring involves identifying particular hospitals that appear to have relatively poor (or relatively good) results. This paper analyzes patient, surgeon, and hospital characteristics associated with serious postdischarge complications of hysterectomy, cholecystectomy, and prostatectomy in patients age 25 and over in Manitoba, Canada, following surgery during 1974 through 1976. The three procedures differ markedly in the ease of prediction of the probability of complications and in the predictive importance of patient, hospital, and physician variables. The predictors worked fairly well for cholecystectomy, somewhat less well for hysterectomy, and not well at all for prostatectomy. Hospital variables were not generally important in the multiple logistic regressions. After controlling for case mix and type of surgery, physician surgical experience was found to account for relatively large differences (almost two to one) in the probability of patient complications following cholecystectomy. Cholecystectomy might be a candidate for certification because of the epidemiology of the operation. As of the mid-1970s, a substantial proportion of the cholecystectomies were being performed by physicians with comparatively little ongoing experience with this type of procedure. Moreover, a monitoring perspective identified one hospital with a significantly higher postcholecystectomy complication rate, even after physician experience was taken into account. Both identifying which procedures should be attended to and focusing on problems following surgery are important beyond Manitoba and highly relevant to such American requirements as Peer Review Organizations. Methods of increasing the efficiency of using claims data for quality assurance studies are outlined.
Continuity of care is defined and measured in terms of care received from a single physician, from several physicians practicing as a group and from physicians seen through referrals. All patients receiving tonsillectomy and adenoidectomy (T and As) in Manitoba for one year, as well as a group of similar individuals treated with respiratory illnesses but not having T and As, were studied. Several patient and physician characteristics were examined to determine their relationship to continuity of care. Continuity consistently increased with patient age, but appeared unrelated to several other variables. The links between continuity of care and quality of care were explored using process and outcome measures of quality. A cross-lagged panel analysis suggested no casual relationship between continuity and quality. These results contradict those of several other studies; they are important in that continuity of care is shown not to reduce one type of error of commission made by practitioners.
Cholecystectomy is one of the most frequently performed elective surgical procedures, and a major contributor to surgery-associated mortality. The well-documented variation in surgical rates across geographic areas has been attributed not simply to differences in disease prevalence but to factors such as varying rates of clinical and radiologic investigation and use of different indications for surgical treatment. The research uses a large claims-based data bank--the hospital and medical files maintained by the Manitoba Health Services Commission. The study focused first on the incidence of gallbladder operations in Manitoba's six rural and three urban areas. Age-adjusted surgical rates varied across regions from more than 50 operations per 10,000 persons aged 25 and over to less than 42. Such variation was considerably less than that noted earlier for the tonsillectomy/adenoidectomy (T&A) operation. Cholecystectomy and T&A rates were not significantly correlated across regions. Moreover, a region's cholecystectomy rate and its 'supply' of operating physicians (measured by a physician-to-population ratio) were not significantly associated. Because a large number of referrals to surgeons in urban centers take place, an analytical distinction between surgery done within the region and that done outside the region has been made. Some movement of rural patients with more serious conditions to urban hospitals is found. Questions of regionalization of surgery are discussed using 9 years of data on mortality following cholecystectomy and biliary tract surgery.
Interest in research on health care has become quite substantial, in part as a result of the recent emergence of public-policy concern for quality assurance and cost-containment. Yet, the essence of this novel line of research has remained, regrettably, a matter of confusion. In particular, the distinction between health care research on one side and health research on the other is being missed in some eminent writings. We emphasize that, properly, the former is to be viewed as having health care, rather than health, as its object, and as being largely descriptive fact-finding about the nature and occurrence of various processes of health care. In these terms it serves policy and administrative decisions in the context of whatever knowledge is available from health research--as to the health consequences of such processes of care. Health research (applied), in turn, addresses the nature and occurrence of phenomena of health (their frequency)--in relation to type of health care, inter alia. Using the example of the North Karelia project, we illustrate the negative consequences of including under health care research inquiries into the premises of health care--notably studies on the effects of care on health outcome.
The impact of an aging population on the health care system is a primary speculative concern for health policy. Unique data from a large sample of 4,263 decedents aged 45 years and over in Manitoba, Canada, describe actual utilization in the four years prior to death: all hospitalizations, nursing home stays, and ambulatory physician contacts. Total expenditures associated with dying do increase with age, but even among the very elderly many deaths have few expenditure consequences. Apocalyptic scenarios for the health care system may be premature.