Coding accuracy of hospital discharge data for elderly survivors of myocardial infarction

OBJECTIVE

To assess the coding accuracy of primary and secondary discharge diagnoses in the Quebec hospital discharge database for elderly persons with myocardial infarction (MI).

DESIGN

Retrospective chart review in a convenience sample of six Montreal hospitals. The diagnoses listed in the medical chart were compared with those listed in the hospital discharge database. For each subject, the Charlson comorbidity index was calculated twice, once based on the medical chart and again based on the hospital discharge database.

PATIENTS

Subjects aged 65 years and over who had an MI coded as the primary discharge diagnosis in the hospital discharge database and who were discharged alive.

MAIN RESULTS

For 234 MI survivors, the positive predictive value (ie, probability that a patient with MI reported in the hospital discharge database had an MI diagnosed by the discharging physician) for coding MI was 0.96 (95% CI 0.94, 0.98). Comorbid medical conditions and complications of the MI were under-reported in the hospital discharge database, which meant that the Charlson index based on the hospital discharge database was an average of 0.71 units lower than the Charlson index based on the medical chart.

CONCLUSIONS

When studying survivors of MI by using hospital discharge databases, the advantages must be weighed against potential drawbacks in the quality of the information. Hospital discharge databases are almost as reliable as medical charts for identifying MI patients, but there is substantial under-reporting of comorbid medical conditions.

Use of standardized patients to assess between-physician variations in resource utilization

CONTEXT

As medical costs are increasingly being scrutinized, there is heightened interest in defining variations in physician behavior in clinical settings.

OBJECTIVE

To evaluate if standardized patient (SP) technology is a reliable and feasible method of studying interphysician variations in test ordering, referral requests, prescribing behavior, and visit costs.

DESIGN

The study was conducted with blinded SP visits to family medicine and internal medicine residents, university-affiliated family physicians, and community-based family physicians. Resource utilization and visit costs were assessed using test requisitions, consult requests, and prescriptions that were collected by the SPs.

SETTING

Physicians' offices in ambulatory care, hospital-based clinics and in the community.

PARTICIPANTS

Four persons (aged 57-77 years) trained to simulate having osteoarthritis of the hip. In one simulation, the patient had gastropathy due to nonsteroidal anti-inflammatory drug use, and in the other, the patient sought therapy for hip discomfort.

MAIN OUTCOME MEASURES

Reliability of cost estimates of physician services, tests, consultations, prescriptions, and total visits and test-ordering behavior for nonsteroidal anti-inflammatory gastropathy.

RESULTS

Overall, 112 (63%) of the physicians who were sent invitations to the study agreed to participate. Of 312 total SP visits conducted over a 1-year period, unblinding due to SP detection occurred on 36 occasions (11.5%). Reliable cost estimates of physician services, tests, and consultations, and moderately reliable estimates of total visit costs, were obtained with 4 visits per practicing physician and with 2 visits per resident. There were extreme variations in total visit costs generated by the study physicians. A small number of physicians had a major impact on this variability.

CONCLUSION

Standardized patient technology provides a reliable, feasible method to assess variations in resource utilization between physicians.

Characteristics of physicians who frequently prescribe long-acting benzodiazepines for the elderly

Long-acting benzodiazepines (LABZs) are relatively contraindicated for elderly patients because they increase the risk of impaired cognitive function, falls, and hip fractures. The purpose of this study was to identify the characteristics of physicians who frequently prescribe LABZs for elderly patients. The authors examined the prescribing profile of 4,976 physicians who saw at least 20 elderly Quebec medicare registrants in 1990. Physicians who frequently prescribed LABZs for their elderly patients were more likely to have graduated before 1979, to be general practitioners as opposed to specialists, to practice in long-term care settings, and to have graduated from a medical school in Quebec as opposed to other schools in Quebec, in other provinces, or in other countries. The authors have identified several characteristics of physicians who frequently prescribed LABZs for the elderly. Strategies to improve prescribing in this field should target this group of physicians.

The Office of the Future Project: the integration of new technology into office practice. Academic detailing through the super highway. Quebec Research Group on Medication Use in the Elderly

Effective management of drug therapy in the elderly is a challenge for primary-care physicians. There are 20,400 drugs approved for marketing in Canada. Most elderly patients will fill 33 prescriptions per year and take 5 different medications. To be a safe prescriber in the 1990s, physicians need to be aware that 33,000 drug interactions, 6,500 drug-disease contraindications, and 3,500 drug-allergy contraindications have been documented. Inappropriate prescribing is a problem in the elderly. At least one inappropriate prescription is given to 12% to 46% of seniors, and 25% of drug-related hospital admissions are due to prescribing errors. Half of all physicians will write at least one inappropriate prescription for an elderly patient each year, and one quarter of inappropriate prescriptions will be created by the presence of multiple prescribing physicians. Academic detailing is the most effective approach to improve physician prescribing. However, it is an expensive intervention that must be limited to a small number of drugs and conditions, and it must be continued to retain its effectiveness. Furthermore, it fails to address the problems created by multiple prescribers. In this project, we developed a prototype of the future office practice. Physicians are equipped with personal computers and expert prescribing-system software. This electronic academic detailer reviews all current medications for a patient, identifies therapeutic duplications, generates alerts for 50 prescribing problems that have been identified as clinically relevant by a Canadian expert panel, suggests suitable alternatives, and reviews all new prescriptions for potential problems. Information on all prescriptions received by the physicians' elderly patients is downloaded weekly from the provincial prescription claims database, so that the primary physician is able to coordinate and manage all drugs prescribed to their patients by all physicians. The effectiveness of this intervention is being evaluated in a randomized controlled trial of 110 physicians and approximately 16,000 elderly patients in Montreal. We will test whether the intervention reduces the rate of inappropriate prescribing, as well as the rate of drug-related injuries and hospitalizations among patients treated by physicians in the experimental group.

[Characteristics of physicians prescribing more psychotropic drugs to women than to men]

In industrialized countries, gender differences observed in health condition and the use of medical services appear insufficient to explain a greater consumption of psychotropic drugs in women than men. The authors have tested the hypothesis that physician prescribing patterns largely explains this observation. They demonstrate, using data from the Régie de l'assurance maladie du Québec for people aged 65 and over, that physicians' sociodemographic and practice characteristics are significantly associated with the percentage of men and women who receive a psychotropic drug prescription in their practice.

Defining inappropriate practices in prescribing for elderly people: a national consensus panel

OBJECTIVE

To develop a consensus-based list of inappropriate practices in prescribing for elderly people.

DESIGN

Mail survey of a 32-member national panel.

SETTING

Academic medical centres across Canada.

PARTICIPANTS

Thirty-two specialists selected arbitrarily, including 7 clinical pharmacologists, 9 geriatricians, 8 family practitioners and 8 pharmacists.

OUTCOME MEASURES

Consensus that the practice would introduce a substantial and significant increase in the risk of serious adverse effect and is common enough that its curtailment would decrease morbidity among elderly people, ranking of clinical importance of the risk, and availability of equally or more effective and less risky alternative therapy.

RESULTS

The 32-member national panel developed a list of 71 practices in prescribing for elderly people and rated the clinical significance of each on a scale of 1 (not significant) to 4 (highly significant). The practices in prescribing identified fell into 3 categories: drugs generally contraindicated for elderly people, drug-disease interactions and drug-drug interactions. The mean significance rating was greater than 3 for 39 practices. For each practice, alternative therapies were recommended. There was surprising congruence among the specialists on the significance rating and the suggested alternative therapies.

CONCLUSION

The authors have developed a valid, relevant list of inappropriate practices in prescribing for elderly people, to be used in a practice-based intervention study.

Exposure to varying levels of contaminants and symptoms among workers in two office buildings

OBJECTIVES

We hypothesized that exposure to contaminants would be associated with symptoms reported by office workers.

METHODS

In two mechanically ventilated office buildings in. Montreal, the outdoor air supply was manipulated for 6 weeks, while symptoms were reported and environmental parameters were measured at multiple sites.

RESULTS

Contaminant concentrations varied considerably, in part related to experimental changes in outdoor air supply. Eye symptoms were reported with higher dust and with higher concentrations of nitrogen dioxide. Mucosal symptoms were increased with higher TVOCs, higher nitrogen dioxide, and higher total contaminant load. Systemic symptoms were associated with higher dust levels.

CONCLUSIONS

Symptoms reported by the workers were associated with increased concentrations of several contaminants and a summary measure of all contaminants.

Do too many cooks spoil the broth? Multiple physician involvement in medical management of elderly patients and potentially inappropriate drug combinations

OBJECTIVES

To determine (a) whether the risk of a potentially inappropriate drug combination (PIDC) increases with the number of physicians involved in the medical management of an elderly patient and (b) whether the risk of a PIDC is reduced if a patient has a single primary care physician or a single dispensing pharmacy, or both.

DESIGN

Cross-sectional retrospective provincial database study.

PARTICIPANTS

A regionally stratified random sample of 51,587 elderly medicare registrants in Quebec who (a) visited at least one physician in 1990, (b) were not living in a health care institution for the entire year and (c) had been dispensed at least one prescription for a cardiovascular drug, a psychotropic drug or a nonsteroidal anti-inflammatory drug (NSAID).

OUTCOME MEASURES

Information on all physician visits and drugs dispensed during 1990. Physician claims were used to identify the number of physicians involved in a patient's management and whether the patient had one primary care physician. Prescription claims were used to identify the number of PIDCs, prescribing physicians and dispensing pharmacies.

RESULTS

The prevalence of PIDCs ranged from 4.0% (among those in the NSAID group) to 20.3% (among those in the psychotropic drug group). Of the PIDCs identified, 17.6% to 25.8% resulted from contemporaneous prescribing by different physicians. The number of prescribing physicians was the most important risk factor for a PIDC in all drug groups (odds ratio [OR] 1.44 to 1.71). The presence of a single primary care physician lowered the risk for cardiovascular and psychotropic PIDCs (OR 0.70 and 0.79 respectively) but not for NSAID PIDCs (OR 0.94). The use of a single dispensing pharmacy lowered the risk of a PIDC in all drug groups (OR 0.68 to 0.79).

CONCLUSION

The greater the number of physicians prescribing medications for an elderly patient, the greater is the risk that the patient will receive a PIDC. A single primary care physician and a single dispensing pharmacy may be "protective" factors in preventing PIDCs.

Who should rate candidates in an objective structured clinical examination?

PURPOSE

To determine who is the better rater of history taking in an objective structured clinical examination (OSCE): a physician or a standardized patient (SP).

METHOD

During the 1991 pilot administration of an OSCE for the Medical Council of Canada's qualifying examination, five history-taking stations were videotaped. Candidates at these stations were scored by three raters: a physician (MD), an SP observer (SPO), and an SP rating from recall (SPR). To determine the validity of each rater's scores, these scores were compared with a "gold standard", which was the average of videotape ratings by three physicians, each scoring independently. Analysis included both correlations with the standard and a repeated-measures analysis of variance (ANOVA) comparing raters' mean scores on each station with mean scores of the gold standard.

RESULTS

Ninety-one videotapes were scored by the "gold-standard" physicians. Correlations with the standard showed no clear preference for MD, SPO, or SPR raters. ANOVAs revealed significant differences from the standard on three stations for the SPR, two stations for the SPO, and one stations for the MD.

CONCLUSIONS

An MD rater is less likely to differ from a standard established by a consensus of MD ratings than are SP raters rating from recall. If an MD cannot be used, an SP observer is preferable to an SP rating from recall.

Questionable prescribing for elderly patients in Quebec

OBJECTIVE

To estimate the prevalence of questionable and rational high-risk prescribing among elderly people of the three drug groups most commonly implicated in drug-related illness: cardiovascular drugs, psychotropic drugs and nonsteroidal anti-inflammatory drugs (NSAIDs).

DESIGN

Retrospective prevalence study; all prescription and billing records for the period Jan. 1 to Dec. 31, 1990, for the study sample were retrieved from the relevant provincial databases of the Régie de l'assurance-maladie du Québec.

SETTING

Quebec.

PARTICIPANTS

Regionally stratified random sample of 63,268 elderly medicare registrants who made at least one visit to physician in 1990 and were not living in a health care institution for the entire year.

MAIN OUTCOME MEASURE

Prescription information was examined for three types of high-risk prescribing: rational and questionable drug combinations, excessive treatment duration and drugs relatively contraindicated for use in elderly people.

RESULTS

Overall, 52.6% of the patients experienced one or more events of high-risk prescribing, and 45.6% experienced at least one that was questionable. High-risk prescribing was most prevalent for psychotropic drugs, and questionable prescribing was more frequent than rational prescribing in this drug group. An estimated 30.8% of the total elderly population in Quebec received benzodiazepines for more than 30 consecutive days, 12.9% received a long-acting benzodiazepine, and 13.0% received a questionable high-risk psychotropic drug combination. The prevalence of high-risk prescribing was higher among the women than among the men and increased with age until 75 to 84 years. There were significant unexplained differences between regions in the regional prevalence of high-risk prescribing, particularly of psychotropic drugs.

CONCLUSION

The prevalence of questionable high-risk prescribing, especially of psychotropic drugs, is substantial among elderly people. This may be a potentially important and avoidable risk factor for drug-related illness in elderly people.

Compliance and cognitive function: a methodological approach to measuring unintentional errors in medication compliance in the elderly. McGill-Calgary Drug Research Team

This study describes the development of a method for assessing the relationship between cognitive function, comprehension, and compliance with medication. We assessed multiple aspects of cognitive performance, medication planning ability, and medication compliance in a convenience sample of 20 outpatients. Using a test battery that measured mental status, attention/concentration, memory function, and motor strength and dexterity, we found that: (1) standard mental status assessment was poorly correlated with memory function; (2) attention/concentration and memory were related to medication planning accuracy; (3) motor dexterity and strength were related to the ability to access medications; and (4) visual perception and memory were the skills most strongly correlated with medication compliance. Findings suggest that aspects of attention/concentration, visual and verbal memory, and motor function which are untapped by simple mental status assessment are related to medication access, planning, and compliance in elderly patients.

The feasibility of using a double blind experimental cross-over design to study interventions for sick building syndrome

Methodological problems have limited scientific investigation of the causes of and solutions for sick building syndrome. The feasibility of using an experimental double blind cross-over study to resolve many of these methodological problems was assessed in a pilot study. The experimental intervention was to vary the amount of outdoor air from 10 cubic feet per minute per person (cfmpp) to 20 cfmpp or 50 cfmpp by central manipulation of the building heating, ventilation and air-conditioning (HVAC) system. Over 6 consecutive study weeks, 2 trials of rates were administered in random order. Study subjects and investigators of the study were blinded to intervention sequence. Unblinding, office environment rating and symptom occurrence were measured weekly. Of 305 eligible workers, 254 participated. Problems were encountered in delivering the lowest dose of ventilation due to building leakage. The prevalence of symptoms diminished steadily over the 6 study weeks, time trends which could be controlled by recommended design modifications. Blinding to the intervention was successfully maintained. Weekly non-response did not introduce a response bias but reduced the number of subjects available for analysis by one-third for each trial. We conclude that this design, with certain modifications, is feasible to evaluate many proposed interventions for sick building syndrome.

An initial evaluation of learning units to facilitate problem solving and self-directed study (portable patient problem pack)

This paper describes the initial evaluation of the portable patient problem pack, a learning unit designed to facilitate the development of problem-solving skills and stimulate self study. A cross-over design using two neurological patient problems, each presented in two formats (simulated patient and P4), was used with a sample of twenty-nine volunteer nursing and medical students. The results indicate that the P4 appears to be feasible and effective in stimulating problem solving and self-directed study. The suggested concurrent validity, low cost of production, and implementation make it a potentially potent tool for evaluation.

Bedside clinics in neurology. An alternate format for the one-day course in continuing medical education

Five one-day workshops entitled "Bedside Clinics in Neurology" were conducted and evaluated at the annual American Medical Association conventions during the past four years. A problem-based, student-centered, small-group approach using simulated patient problems was used as a means of avoiding the educational assumptions made by the more conventional teacher-centered lecture-discussion format. The response by participants in an immediate evaluation and six-month follow-up of the last two workshops indicated that (1) this format was stimulating, (2) the workshop would be attended again if conducted in a different topic, (3) the participants would pay a mean cost of $70, and (4) the workshop provided practical and relevant information for their day-to-day practice situation. Further evaluation to assess the educational effectiveness of this format is being planned.