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A growing number of Americans have no usual source of care, perhaps reflecting declining access to care
Individuals with a usual source of care, either a physician's office or outpatient clinic, typically have better access to care and are more likely to receive needed medical services ranging from immunizations to cancer screening. They also are more apt to be diagnosed early, receive appropriate care, and report satisfactory outcomes. However, compared with 1987, 4 percent fewer individuals in 1992 had a regular source of care, and it was more likely to be a hospital outpatient department rather than a physician's office, finds a study by Carolyn M. Clancy, M.D., of the Agency for Health Care Policy and Research and her colleagues from the Association of American Medical Colleges and the University of Maryland. This may reflect deteriorating access to care, notes Dr. Clancy.
The researchers analyzed data from the 1987 and 1992 National Health Interview Surveys and found that from 1987 to 1992, the estimated number of adult Americans who did not have a usual source of care rose from 30 to 39 million (17 to 21 percent). Identification of doctors' offices as a usual source of care decreased from 66 to 59 percent, whereas identification of health maintenance organizations and hospital outpatient departments increased. In fact, nearly twice as many patients were likely to identify a hospital outpatient department rather than a doctor's office as a usual source of care in 1992 compared with 1987. Hospital outpatient departments typically offer less continuity of care than doctors' offices. Identification of hospital emergency rooms and other sites as usual sources of care did not change.
Every population group experienced an increase in the lack of a usual source of care. However, Hispanics, individuals with less education or lower income, those in worse health, and residents of the South or rural areas experienced particularly large increases in the odds of not having a usual source of care from 1987 to 1992. The authors conclude that barriers to care are no longer reserved for the socioeconomically disadvantaged but are felt by Americans in every walk of life.
See "Changes in usual sources of medical care between 1987 and 1992," by Ernest Moy, M.D., M.P.H., Barbara A. Bartman, M.D., M.P.H., Dr. Clancy, and Llewellyn J. Cornelius, Ph.D., in the Journal of Health Care for the Poor and Underserved 9(2), pp. 126-138, 1998.
Reprints (AHCPR Publication No. 98-R071) are available from the AHCPR Publications Clearinghouse.
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HMO enrollment not associated with delayed ER access for patients with heart attack symptoms
There is growing concern that by attempting to limit unnecessary care in hospital emergency departments (EDs), health maintenance organizations (HMOs) may be creating financial hurdles that discourage or delay their enrollees from seeking needed emergency treatment. As of 1993 at least, HMO insurance did not delay patients with symptoms of acute cardiac ischemia (ACI, heart attack or angina) in seeking emergency care. They were as likely to summon an ambulance and arrive at the hospital as soon after symptom onset as indemnity-insured patients, concludes a study supported in part by the Agency for Health Care Policy and Research (HS07360 and National Research Service Award training grant T32 HS00060).
A delay of even 1 hour in treating heart attack patients can reduce by half the effectiveness of thrombolytic (clot-busting) therapy in preventing death, explains Harry P. Selker, M.D., M.S.P.H., of the New England Medical Center (NEMC). Dr. Selker and his colleagues from NEMC and Tufts University used data collected prospectively on 6,604 HMO- and indemnity-insured patients arriving at EDs of 10 adult care hospitals in 1993 within 24 hours of ACI symptom onset (left arm, jaw, or upper abdominal pain; dizziness; nausea or vomiting; or labored breathing). The hospital-matched sample of HMO-insured and indemnity-insured patients showed no difference in the rate of ambulance use (which was associated with a nearly 2 hours shorter time-to-treatment) or duration of time from symptom onset to ED arrival.
However, since 1993 HMOs have erected more barriers to emergency services—for example, by establishing substantial copayments for ED visits or, in some parts of the country, paying for ambulance services on a capitated basis. In addition, indemnity plans have added their own systems or preauthorization requirements, copayments, and selective reimbursement. The researchers conclude that caution should be used in applying their results to current HMOs and that access to 911 and emergency services needs ongoing monitoring.
See "Insurance type and the transportation to emergency departments of patients with acute cardiac ischemia: The ACI-TIPI trial insurance study," by Harold A. Picken, M.D., Deborah R. Zucker, Ph.D., M.D., John L. Griffith, Ph.D., Joni R. Beshansky, R.N., M.P.H., and Dr. Selker, in the June 1998 American Journal of Managed Care 4(6), pp. 821-827.
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Many people who suffer chronic headache pain are unable to participate fully at work
Like chronic back pain sufferers, people who have chronic headache pain often are unable to work. Pain can impair work performance through its impact on physical functioning, such as the ability to lift, walk or sit, or perform movements required by a work task. Pain also can impair work performance through its effects on cognitive, emotional, and interpersonal capacities required to be effective at work, such as concentration, motivation, energy, and the ability to engage in positive interactions with others.
According to a study supported in part by the Agency for Health Care Policy and Research (HS06168), over one-third (36 percent) of those who suffer from moderate to severe headache pain, compared with 48 percent of people who suffer from moderate to severe back pain, were unable to obtain or keep full-time work at some time during a 3-year period. Only 4 percent of headache patients who had low-intensity or no pain reported that their work was similarly affected during that timeframe.
Study participants were interviewed three times over a 2-year period; about 13 percent of all headache patients reported at one or more of the interviews that they were unable to obtain or keep full-time work in the prior year because of their pain condition, compared with 18 percent of all back pain patients who were unable to do so. Migraine sufferers were nearly twice as likely as headache patients without migraine and depressed patients were twice as likely as nondepressed patients to report being unable to obtain or keep full-time work because of headaches.
The findings from this comparison of headache and back pain patients surprised Michael Von Korff, Sc.D., of Group Health Cooperative of Puget Sound, and his colleagues because headache, especially migraine, is an intermittent disorder while back pain is more persistent. This study included 662 headache patients and 1,024 back pain patients who visited a primary care physician at a large Seattle-area health maintenance organization at baseline, 1 year, and 2 years.
For more details, see "Reduced labor force participation among primary care patients with headache," by Paul Stang, Ph.D., Dr. Von Korff, and Bradley S. Galer, M.D., in the May 1998 Journal of General Internal Medicine 13, pp. 296-302.
Most primary care practices will need help in using quality improvement techniques
Over the past decade, the application of quality management techniques to health care institutions—better known as continuous quality improvement (CQI) or total quality management—has motivated considerable efforts to refocus how we approach the collective challenge of improving health care delivery. CQI has been attempted most often in large institutions and nonclinical settings. However, research has shown that most people prefer to obtain their care in small scale practice settings. Thus, a recent study supported by the Agency for Health Care Policy and Research (HS08091) attempted to apply CQI principles to address clinical problems in small practice settings and to involve physicians in the process.
Despite a mostly favorable attitude toward CQI, the study found that clinicians participating in the study had a limited depth of understanding or involvement, and that there was considerable room for improvement. The study, described here, was conducted by Leif I. Solberg, M.D., of HealthPartners Research Foundation, Minneapolis, MN, and colleagues. In an editorial accompanying Dr. Solberg's article, Carolyn M. Clancy, M.D., Acting Director of AHCPR's Center for Primary Care Research, points out that knowledge is not enough; improvements in care must be linked with incentives and strategies for change.
Solberg, L.I., Brekke, M., Kottke, T.E., and Steel, R.P. (1998). "Continuous quality improvement in primary care: What's happening." Medical Care 36(5), pp. 625-635.
The researchers conducted three surveys of the clinicians, nurses, and other staff in 44 primary care clinics in the metropolitan area of Minneapolis and St. Paul, MN. The surveys addressed attitudes about quality improvement, previous efforts by the clinics to use process improvement teams, and the extent to which the clinics' organizational cultures were perceived as supporting quality.
The surveys showed that primary care providers appear to have mixed attitudes and a limited understanding of CQI. Although they generally have a positive attitude about CQI, they aren't necessarily sure that reducing variation in care is desirable or that clinic leaders are committed to CQI.
Although about half (20) of the 44 participating clinics reported that there had been at least one process improvement team at their clinic, 60 percent of clinicians had never been involved with such a team. Many of the teams did not complete the quality improvement actions, especially the actions that should make the most difference to success, that is, those involved in evaluating the implemented plan's success.
Only five teams had completed a process improvement cycle—that is, they developed an evaluation plan and used data to evaluate the plan's implementation. That may explain in part why only 7 of the 12 teams (58 percent) reported improvements in the problem that they had been formed to address, such as reducing waiting time, increasing patient satisfaction, or improving urgent care arrangements.
Dr. Solberg and his colleagues conclude that despite relatively favorable attitudes and some CQI activities, clinics will need help to build skill and experience to achieve improvements in care.
Clancy, C.M. (1998). "Continuous quality improvement and primary care." Medical Care 36(5), pp. 619-620.
According to this editorial, the results of the study by Dr. Solberg and colleagues suggest a striking contrast between clinicians' perceptions of the "problem" of clinical performance and the basic assumptions of CQI. The findings also underscore the collective need for additional information on organizational and clinician factors that motivate sustained and successful efforts at quality improvement, notes Dr. Clancy.
This information could help explain why a group of motivated clinicians apparently were unmoved by a need to reduce variations in practice. It may be that primary care clinicians take tremendous pride in customizing their approach to individual patients. The unspoken inference may be that reducing variations will require elimination of aspects of daily practice that are both rewarding and valued by patients.
If clinicians are not persuaded that reducing variations in practice based on good evidence is desirable, no quality improvement strategy is likely to succeed for very long, explains Dr. Clancy. The long-term prognosis for CQI in primary care—or any setting—will depend on clinicians and those involved in quality improvement reaching consensus on which variations should be reduced or eliminated and which should be celebrated because they are responsive to patients' preferences. Dr. Clancy concludes that the historical roots of quality assessment, focused on the hospital, will require extensive transformation to be useful in small practices.
Conference participants examine organizational issues in delivery of primary care to the elderly
The massive restructuring of American health care is bound to have a lasting impact on how primary care is delivered to the elderly. To examine this issue, the Agency for Health Care Policy and Research and the National Institute on Aging cosponsored a national invitational conference, "Aging and Primary Care: Organizational Issues in the Delivery of Health Care for Older Americans." About 50 attendees with expertise in geriatrics, nursing, the social and behavioral sciences, and health care management and policy met in Washington, DC, in 1996. The underlying goal of the conference was to examine the potential of an organizational research perspective for expanding the current knowledge base on the determinants of different health care structures and their consequences for older people.
Overall, the conference examined the structure, culture, and process of health care organization; the mix, capacities, values, and role played by various health care professionals and agencies; and the interaction between providers and the people they serve.
Participants examined the impact of managed care organizational, economic, and structural characteristics on both the delivery of health care to the elderly and their responses to and outcomes of that care. Attendees explored research linking key internal organizational characteristics, such as size, mission, ownership, and managerial communication and control structures, to patient outcomes. Another focus was on the nature and extent of relationships among multi-institutional systems, insuring organizations, and other organizations that deliver health care to older Americans.
How elderly individuals' decisions, behaviors, and preferences may change in response to health care system changes, and whether the altered health care system will be responsive to the needs of older clients were also examined. And finally, attendees examined methodological problems and barriers in performing research on organizational and patient factors related to the delivery of primary care to older Americans and identified research priorities.
Following the conference, six primary working papers were reworked for publication in a special supplement to the journal Health Services Research:
- Ory, M.G., Cooper, J., and Siu, A.L., "Toward the development of a research agenda on organizational issues in the delivery of health care to older Americans," pp. 287-297.
- Sofaer, S., "Aging and primary care: An overview of organizational and behavioral issues in the delivery of health care services to older Americans," pp. 298-321.
- Wholey, D.R., Burns, L.R., and Lavizzo-Mourey, R., "Managed care and the delivery of primary care to the elderly and the chronically ill," pp. 322-353.
- Zinn, J.S. and Mor, V., "Organizational structure and the delivery of primary care to older Americans," pp. 354-380.
- Kaluzny, A.D., Zuckerman, H.S., and Rabiner, D.J., "Interorganizational factors affecting the delivery of primary care to older Americans," pp. 381-401.
- Counte, M.A., "The emerging role of the client in the delivery of primary care to older Americans," pp. 402-423.
- Fennell, M.L., and Flood, A.B., "Key challenges in studying organizational issues in the delivery of health care to older Americans," pp. 424-433.
For more information, see "Organizational issues in the delivery of primary care to older Americans," Special Supplement to Health Services Research 33(2, Part II), June 1998.
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Health Care Delivery
Treating suspected TB pending lab results often minimizes both the risk of death and health care costs
Even with commonly available rapid laboratory culture tests to diagnose Mycobacterium tuberculosis, the bacteria that causes tuberculosis (TB), it takes 2 or 3 weeks to obtain results. While waiting for these results, the average patient's risk of death and health care costs can be reduced by treating all patients suspected of having TB who have a positive acid-fast bacillus (AFB) sputum smear or are infected with the human immunodeficiency virus (HIV). HIV-positive patients should be treated even if the AFB smear is negative, since they are at high risk for TB. The potential for deaths from drug toxicity in treating many people without TB is slightly outweighed by the potential deaths of not treating those with smear-negative disease pending culture results, according to a study supported in part by the Agency for Health Care Policy and Research (National Research Service Award F32 HS00079).
The researchers found, for example, that treatment of HIV-infected patients who have AFB-negative smears decreases deaths by 2 percent on average at an additional cost of $8,000 per life saved. This is still lower than costs per life-year-saved for other medical interventions such as HIV screening of blood donors. When the prevalence of multi-drug resistant TB (MDR-TB) in a community exceeds 9.6 percent, drug-resistant therapy for AFB smear-positive patients (prior to results from culture and drug-resistant tests), rather than the initial four-drug regimen recommended for much of the United States (INH, rifampin, pyrazinamide, and ethambutol), minimizes both the risk of mortality and costs. A quinolone drug is added to the regimen for MDR-TB.
This decision analysis by Timothy F. Brewer, M.D., M.P.H., and his colleagues at Harvard Medical School was based on the most recently available U.S. survey data on percentage of TB infections and MDR-TB. The decision model incorporated an average baseline mortality risk, mortality risks from drug toxicity, treated drug-sensitive or drug-resistant TB, and untreated TB.
For more information, see "An effectiveness and cost analysis of presumptive treatment of Mycobacterium tuberculosis," by Dr. Brewer, S. Jody Heymann, M.D., Ph.D., Mary Ettling, Sc.D., and others, in the American Journal of Infection Control 26(3), pp. 232-238, 1998.
Expert panels are being used to gauge the appropriateness of medical procedures
The cornerstone of good care is sound clinical judgment—an ability to determine which interventions (or decisions not to intervene) will consistently benefit individual patients. The problem, of course, is defining and measuring appropriate care and evaluating clinical judgment.
Two recent studies, supported by the Agency for Health Care Policy and Research (HS07185 and HS08071) and briefly summarized here, address these issues. Both assess what is arguably the most respected approach to defining appropriate care—the RAND-University of California at Los Angeles (UCLA) Delphi panel method, for evaluating appropriateness of medical procedures. In this method, researchers develop hundreds of case scenarios based on combinations of clinical factors that could affect patients' net benefits from a given procedure. A multidisciplinary panel of expert clinicians independently rates the scenarios on a nine-point appropriateness scale and then rates them again after discussing areas of disagreement. Analysts use the ratings to categorize each procedure as appropriate, of uncertain appropriateness, or inappropriate.
Shekelle, P.G., Kahan, J.P., Bernstein, S.J., and others (1998, June). "The reproducibility of a method to identify the overuse and underuse of medical procedures." New England Journal of Medicine 338(26), pp. 1888-1895.
In this study, the authors employed the RAND-UCLA method using expert panels stratified for balance in specialty, geography, and type of practice. Three panels rated noncancerous indications for elective hysterectomy; three other panels rated indications for coronary revascularization (angioplasty or bypass surgery). Final panel ratings were used to classify the procedure in each scenario as necessary or not necessary and appropriate or inappropriate.
The rates of agreement among the three coronary-revascularization panels were 95, 94, and 96 percent for inappropriate-use scenarios and 93, 92, and 92 percent for necessary-use scenarios. Agreement among the three hysterectomy panels was 88, 70, and 74 percent for inappropriate-use scenarios. Scenarios depicting necessary use of hysterectomy were not assessed.
Application of individual panels' criteria to real populations of patients resulted in a 100 percent variation in the proportion of cases classified as inappropriate and a 20 percent variation in the proportion of cases classified as necessary. Also, the proportion of procedures that would be deemed inappropriate varied between panels by a factor of two. For example, one panel categorized 7.3 percent of coronary-revascularization procedures provided at
15 New York hospitals as inappropriate compared with 3.8 percent by another panel. Inappropriate elective use of hysterectomy in seven managed care organizations varied from 24 to 52 percent. The authors conclude that although appropriateness criteria may be useful in comparing levels of appropriate procedure use among populations, these criteria should not by themselves be used to direct care for individual patients.
Ayanian, J.Z., Landrum, M.B., Normand, S-L, and others (1998, June). "Rating the appropriateness of coronary angiography—Do practicing physicians agree with an expert panel and with each other?" New England Journal of Medicine 338(26), pp. 1896-1904.
These researchers asked 1,058 internists, family practitioners, and cardiologists in five States (California, Florida, New York, Pennsylvania, and Texas) to rate the appropriateness of coronary angiography after acute myocardial infarction for 20 common indications. Nine clinical experts also rated these indications using the RAND-UCLA Delphi method. Overall, surveyed physicians agreed with clinical experts about the appropriateness of coronary angiography after myocardial infarction for most indications. This suggests that well-designed expert panels can closely reflect the views of practicing physicians.
Cardiologists rated angiography as significantly more appropriate than did primary care physicians for complicated indications. For uncomplicated indications, cardiologists who performed invasive procedures rated angiography as more appropriate than did cardiologists who did not perform such procedures, and primary care physicians and physicians from hospitals providing coronary angioplasty and bypass surgery rated angiography as more appropriate than did physicians from other hospitals.
Physicians from New York and those employed by health maintenance organizations rated angiography as less appropriate than other physicians. More than 50 percent of primary care physicians and cardiologists reported that patient or family requests were an important influence on their decisions, and almost 50 percent of each physician group said on-site availability of angiography was an important consideration in their decision. Understanding differences among practicing physicians in their views about appropriate medical care can help ensure that clinical guidelines and evaluations encompass the views of a range of relevant types of physicians.
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Researchers examine treatment of benign prostatic hyperplasia
Evaluation and treatment of lower urinary tract symptoms in elderly men with benign prostatic hyperplasia (BPH, enlarged prostate) in the United States changed rapidly between 1991 and 1995, with a sharp decline in invasive therapy for BPH. The two studies described here examine the diagnostic procedures and care provided to BPH patients in the early 1990s.
The first study, conducted by researchers at the Agency for Health Care Policy and Research, compares changing patterns of care for BPH with the recommendations set forth in the AHCPR-sponsored clinical practice guideline on BPH which was issued in 1994. The second study shows that men with moderate symptoms of BPH who undergo transurethral resection of the prostate (TURP) have fewer genitourinary problems 5 years later than patients who are simply monitored (watchful waiting). This study was conducted by the Veterans Affairs Cooperative Studies Program. It was supported in part by AHCPR (HS08397, the Patient Outcomes Research Team (PORT) on prostatic diseases). The AHCPR Prostate PORT is led by Michael J. Barry, M.D., of Massachusetts General Hospital.
Baine, W.B., Yu, W., Summe, J.P., and Weis, K.A. (1998, September). "Epidemiologic trends in the evaluation and treatment of lower urinary tract symptoms in elderly male Medicare patients from 1991 to 1995." Journal of Urology 160, pp. 816-820, 1998.
This study of trends in the use of BPH-related procedures shows that transurethral resection of the prostate (TURP) for elderly men with BPH and lower urinary tract symptoms declined 43 percent from 1991 to 1995, with even steeper reductions for open prostatectomy. In addition, the proportion of transurethral resections performed on hospitalized patients decreased from 96 to 88 percent. Age-specific rates for this surgery were highest in the ninth decade, and during the 5-year study period operative rates generally declined more among white than among black men of the same age.
Many of the changes in use of BPH-related diagnostic tests for men with BPH and lower urinary tract symptoms were consistent with the recommendations of AHCPR's BPH practice guideline, but the changes were often already under way before publication of the guideline. Thus, the guideline may have simply codified ongoing modifications to clinical practice rather than eliciting them, according to the researchers. For instance, according to the guideline, filling cystometry, urethrocystoscopy, and imaging of the urinary tract are "tests not recommended" to evaluate BPH. Use of filling cystometry showed an overall decrease from 1991 through 1993 with no perceptible change thereafter. Urethrocystoscopy and excretory urography (an imaging test) performed specifically in cases of BPH declined steadily with overall declines of 35 percent and 60 percent, respectively, during the 5-year study period.
Also, the guideline categorized uroflowmetry, post-void residual urine, and pressure flow studies as "optional diagnostic tests." Use of uroflowmetry increased during the first 3 years, and pressure flow studies increased throughout the 5 years studied, with the former test being performed more frequently than the latter. These findings are based on an analysis of a 5 percent sample of the Health Care Financing Administration's database of Medicare beneficiaries.
Reprints (AHCPR Publication No. 98-R087) are available from the AHCPR Publications Clearinghouse.
Flanigan, R.C., Reda, D.J., Wasson, J.H., and others (1998, July). "5-year outcome of surgical resection and watchful waiting for men with moderately symptomatic benign prostatic hyperplasia: A Department of Veterans Affairs cooperative study." Journal of Urology 160, pp. 12-17, 1998.
Men with moderate symptoms of BPH who undergo transurethral resection of the prostate (TURP) have fewer genitourinary symptoms 5 years later than those who are simply monitored (watchful waiting). While many men do well on watchful waiting, those who undergo TURP after a trial of watchful waiting have less improved bladder functioning than men initially treated with TURP, according to this study by Prostate PORT researchers. They randomized 556 men with moderate symptoms of BPH at nine Veterans Affairs Hospitals to either TURP or watchful waiting and followed them for up to 5 years.
Men who underwent TURP had significantly better outcomes across the board than those in the watchful waiting group. For example, they had half the treatment failure rates (10 vs. 21 percent). Also, 36 percent of men in the watchful waiting group, usually those with the most bothersome genitourinary symptoms, had to cross over to surgery at 5 years. Overall, men who underwent prostatic resection had less genitourinary bother and fewer symptoms, and the rates of acute urinary retention and high residual urinary volume were much less than in men in the watchful waiting group.
Only 1.2 percent of men who underwent surgery had persistent incontinence compared with 2.9 percent of those assigned to watchful waiting. These results underscore the fact that watchful waiting, with or without medication, is a safe treatment choice for many men with moderate symptoms of BPH. On the other hand, for some men delay of surgical resection may have some negative effects on symptom resolution, peak flow rates, and residual urinary volume. The researchers conclude that men whose genitourinary symptoms are bothersome are most likely to benefit from resection.
Medical consultants play a key role in improving outcomes of hip fracture patients
Within a year of hip fracture, 24 percent of elderly Medicare patients die, only 54 percent of those who survive can walk unaided, and only 40 percent can independently perform all physical activities of daily living. The medical consultant has a key role in improving the care and outcomes of hip fracture patients by providing state-of-the-art care and managing preoperative conditions and postoperative complications, according to a recent literature review conducted by researchers at Mount Sinai School of Medicine and supported in part by the Agency for Health Care Policy and Research (HS09459).
Despite the involvement of medical consultants in the care of most hip fracture patients, many internists have no formal training in this condition, and they may be unfamiliar with optimal management of its complications, according to the researchers. They reviewed studies on clinical interventions to improve care of conditions typically encountered by medical consultants in the care of hip fracture patients.
The studies show that surgical repair of hip fracture for medically stable patients within the first 24 to 48 hours lowers 1-year mortality rates and the incidence of confusion and pressure ulcers. Prophylactic antibiotics given for about 24 hours can substantially reduce the risk of deep-wound infections and should probably be administered 0 to 2 hours before surgery.
Strong evidence also supports the use of heparin to prevent deep, venous thrombosis starting at hospital admission. As many as 20 percent of hip fracture patients are severely malnourished. Oral protein supplementation seems to reduce minor postoperative complications, preserve body protein stores, and reduce overall length of hospital stay. Postoperative delirium occurs in up to 61 percent of patients with hip fracture, but it can be prevented by identifying and correcting risk indicators for delirium, such as electrolyte and metabolic laboratory abnormalities. Finally, more than one physical therapy session per day is probably beneficial, note the researchers.
Details are in "The medical consultant's role in caring for patients with hip fracture," by R. Sean Morrison, M.D., Mark R. Chassin, M.D., M.P.P., M.P.H., and Albert L. Siu, M.D., M.S.P.H., in the June 15, 1998, Annals of Internal Medicine 128(12, Pt. 1), pp. 1010-1020.
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