Biomedical subjects

B Chan

Publications and source records attributed to B Chan.

At least 37 records · Page 2Linked to original sources

PubMed2000

FIZZ1, a novel cysteine-rich secreted protein associated with pulmonary inflammation, defines a new gene family.

Bronchoalveolar lavage fluid from mice with experimentally induced allergic pulmonary inflammation contains a novel 9.4 kDa cysteine-rich secreted protein, FIZZ1 (found in inflammatory zone). Murine (m) FIZZ1 is the founding member of a new gene family including two other murine genes expressed, respectively, in intestinal crypt epithelium and white adipose tissue, and two related human genes. In control mice, FIZZ1 mRNA and protein expression occur at low levels in a subset of bronchial epithelial cells and in non-neuronal cells adjacent to neurovascular bundles in the peribronchial stroma, and in the wall of the large and small bowel. During allergic pulmonary inflammation, mFIZZ1 expression markedly increases in hypertrophic, hyperplastic bronchial epithelium and appears in type II alveolar pneumocytes. In vitro, recombinant mFIZZ1 inhibits the nerve growth factor (NGF)-mediated survival of rat embryonic day 14 dorsal root ganglion (DRG) neurons and NGF-induced CGRP gene expression in adult rat DRG neurons. In vivo, FIZZ1 may modulate the function of neurons innervating the bronchial tree, thereby altering the local tissue response to allergic pulmonary inflammation.

Amino Acid Sequence↗

PubMed2000

Effects of humanized monoclonal antibody to rhesus CD11a in rhesus monkey cardiac allograft recipients.

INTRODUCTION: Leukocyte function-associated antigen-1 (LFA-1, CD11a) monoclonal antibody (mAb) affects many leukocyte functions without cell depletion. We hypothesized that the use of a humanized, anti-rhesus modified LFA-1 mAb (H2C12) in rhesus monkeys would cause: (1) prolonged heart allograft survival, (2) inhibition of primary but not secondary antibody responses, and (3) minimal drug toxicity. METHODS AND RESULTS: Control (n=5) and H2C12-treated (n=7) (8-20 mg/kg i.v. on day -1 followed by 10 mg/kg/day) adult male rhesus recipients were inoculated with GP120 protein antigen on day -28 and -1 and grafted with heterotopic abdominal hearts (day 0). Donor-recipient pairs were equally MLR mismatched (4329.8+/-1124.1 CPM controls vs. 7289.0+/-1926.5 treated, P=NS). Mean heart allograft survival as evaluated by daily abdominal palpation was significantly prolonged in high dose recipients (23.0+/-2.6, n=4) vesus controls (8.2+/-1.3, n=5, P<0.02, Mann-Whitney U test). H2C12 treatment did not produce signs of cytokine release or toxicity, was nondepleting, but down-modulated PBL CD11a expression to 43.4+/-3.6% (n=4) of control levels (n=5) at day 7 as demonstrated by flow cytometry. It had no effect on postoperative Con A or MLR and did not prevent mAb clearance due to the rhesus-antihuman antibody response. The addition of mycophenolate mofitil prevented rhesus-antihuman antibody response with therapeutic H2C12 levels seen for >35 days. CONCLUSIONS: The use of this mAb to block CD11a had the benefit of being a well tolerated, highly targeted therapy. These are the first results showing that monotherapy with anti-leukocyte function-associated antigen-1 mAb prolonged survival of MLR mismatched allogenic cardiac grafts in primates.

Animals↗

PubMed2000

Microvascular reconstruction and tracheotomy are significant determinants of resource utilization in head and neck surgery.

BACKGROUND: Successful "critical pathway" design and implementation are dependent on appropriate patient stratification according to those factors that are primary determinants of resource utilization. OBJECTIVES: To test the validity of our previously reported critical pathway design and to determine whether tracheotomy and microvascular reconstruction (MR) are primary determinants of resource utilization. DESIGN: Cost-effectiveness analysis. SETTING: Tertiary referral academic institution. METHODS: Retrospective analysis of data from 133 head and neck surgery cases in which the treatment regimen was based on critical pathways over a 26-month period. OUTCOME MEASURES: Length of stay and total patient charges were used as indices of resource utilization. One-way analysis of variance and t tests were used for statistical analysis of significance. RESULTS: Ninety patients (67.7%) underwent MR; 43 (32. 3%) did not. Seventy-five patients (56.4%) underwent tracheotomy; 58 (43.6%) did not. Four patient groups were constructed in decreasing order of complexity as follows: group 1, patients who underwent both tracheotomy and MR (n = 58); group 2, patients who underwent MR alone (n = 32); group 3, patients who underwent tracheotomy alone (n = 17); and group 4, patients who did not undergo either procedure (n = 26). Both tracheotomy and MR were found to be independent determinants of resource utilization and were additive when both were present. The length of stay varied from 8.4 days (in patients who underwent both procedures) to 6.7 days (in patients who did not undergo either procedure), with intermediate values in cases in which only 1 procedure was performed. The total charges varied in a similar manner from a high of $33,371 to a low of $19,994. Subanalysis with respect to intensive care unit, ward, and operating room charges showed a similar stratification. CONCLUSION: Tracheotomy and MR are both significant determinants of charges and length of stay in head and neck surgery cases and must be considered in the design of strategies to promote efficient resource utilization.

Cost-Benefit Analysis↗

PubMed2000

Assessment of hemodynamic response during focal neural activity in human using bolus tracking, arterial spin labeling and BOLD techniques.

In this study, the hemodynamic response and changes in oxidative metabolism during functional activation were measured using three functional magnetic resonance imaging (fMRI) techniques: the blood oxygenation level-dependent (BOLD) technique, flow-sensitive alternating inversion recovery (FAIR), and bolus tracking (BT) of an MR contrast agent. With these three techniques we independently determined changes in BOLD signal, relative cerebral blood flow (rCBF), and cerebral blood volume (rCBV) associated with brain activation in eight healthy volunteers. In the motor cortex, the BOLD signal increased by 1.8 +/- 0.5%, rCBF by 36.3 +/- 8.2% (FAIR), and 35.1 +/- 8.6% (BT), and rCBV by 19.4 +/- 4.1% (BT) in response to simultaneous bilateral finger tapping. In the visual cortex, BOLD signal increased by 2.6 +/- 0.5%, rCBF by 38.5% +/- 7.6 (FAIR), and 36.9 +/- 8.8% (BT), and rCBV by 18.8 +/- 2.8% (BT) during flickering checkerboard stimulation. Comparing the experimentally measured rCBV with the calculated rCBV using Grubb's power-law relation, we conclude that the use of power-law relationship results in systematic underestimate of rCBV.

Adult↗

PubMed2000

A mixed-penalty biphasic finite element formulation incorporating viscous fluids and material interfaces.

The fluid viscosity term of the fluid phase constitutive equation and the interface boundary conditions between biphasic, solid and fluid domains have been incorporated into a mixed-penalty finite element formulation of the linear biphasic theory for hydrated soft tissue. The finite element code can now model a single-phase viscous incompressible fluid, or a single-phase elastic solid, as limiting cases of a biphasic material. Interface boundary conditions allow the solution of problems involving combinations of biphasic, fluid and solid regions. To incorporate these conditions, the volume-weighted mixture velocity is introduced as a degree of freedom at interface nodes so that the kinematic continuity conditions are satisfied by conventional finite element assembly techniques. Results comparing our numerical method with an independent, analytic solution for the problem of Couette flow over rigid and deformable porous biphasic layers show that the finite element code accurately predicts the viscous fluid flows and deformation in the porous biphasic region. Thus, the analysis can be used to model the interface between synovial fluid and articular cartilage in diarthrodial joints. This is an important step toward modeling and understanding the mechanisms of joint lubrication and another step toward fully modeling the in vivo behavior of a diarthrodial joint.

Biomechanical Phenomena↗

PubMed2000

A multi-mutant herpes simplex virus vector has minimal cytotoxic effects on the distribution of filamentous actin, alpha-actinin 2 and a glutamate receptor in differentiated PC12 cells.

To develop effective gene therapy techniques that target populations of neurons in the spinal cord, suitable vectors must be developed that will undergo efficient, retrograde transport from an appropriate peripheral site and will not be cytotoxic. Our previous work (LeVatte et al, 1998a) has demonstrated that a replication defective herpes simplex virus vector 14Hdelta3vhsZ, that has been substantially detoxified, is retrogradely transported from peripheral sites and can infect large numbers of the targeted spinal neurons. We plan to develop targeted gene therapy approaches designed to modulate the excitatory glutamatergic methyl-D-aspartate (NMDA) receptor in spinal cord neurons as a means of ameliorating a form of episodic high blood pressure that occurs after spinal cord injury. In this report, we demonstrate that, in differentiated PC12 cells, a neuronal-like cell line, the virus vector does not appear to alter aspects of the cytoskeletal architecture important to the proper distribution of the NMDA receptor. In turn, the distribution of endogenous NMDA receptor 1 subunit protein (NMDAR1) or a transfected NMDAR1-green fluorescent fusion protein was also found to be unaltered after vector infection. However, whereas endogenous NMDAR1 distribution was maintained, vector infection did tend to reduce the level of its expression. This drop in endogenous NMDAR1 expression coincided with the expression of the HSV immediate early genes ICP0 and ICP27 over the first 24-48 h. These results indicate that the 14Hdelta3vhsZ herpes simplex virus vector is suitable to use in future strategies to alter the level of gene expression in targeted populations of spinal cord neurons.

Actin Cytoskeleton↗

PubMed2000

The financial performance of hospitals belonging to health networks and systems.

The U.S. health industry is experiencing substantial restructuring through ownership consolidation and development of new forms of interorganizational relationships. Using an established taxonomy of health networks and systems, this paper develops and tests four hypotheses related to hospital financial performance. Consistent with our predictions, we find that hospitals in health systems that had unified ownership generally had better financial performance than hospitals in contractually based health networks. Among health network hospitals, those belonging to highly centralized networks had better financial performance than those belonging to more decentralized networks. However, health system hospitals in moderately centralized systems performed better than those in highly centralized systems. Finally, hospitals in networks or systems with little differentiation or centralization experienced the poorest financial performance. These results are consistent with resource dependence, transaction cost economics, and institutional theories of organizational behavior, and provide a conceptual and empirical baseline for future research.

American Hospital Association↗

PubMed1999

Intra-tRNA distance measurements for nucleocapsid proteindependent tRNA unwinding during priming of HIV reverse transcription.

We report here the direct measurement of intra-tRNA distances during annealing of the tRNA primer to the HIV RNA genome. This key step in the initiation of retroviral reverse transcription involves hybridization of one strand of the acceptor arm of a specific lysine tRNA to the primer binding site on the RNA genome. Although the mechanism of tRNA unwinding and annealing is not known, previous studies have shown that HIV nucleocapsid protein (NC) greatly accelerates primer/template binary complex formation in vitro. An open question is whether NC alone unwinds the primer or whether unwinding by NC requires the RNA genome. We monitored the annealing process in solution by using fluorescence resonance energy transfer (FRET). Distance measurements demonstrate unequivocally that the tRNA acceptor stem is not substantially unwound by NC in the absence of the RNA genome, that is, unwinding is not separable from hybridization. Moreover, FRET measurements show that both heat- and NC-mediated annealing result in an approximately 40-A increase in the separation of the two ends of the tRNA acceptor arm on binding to the template. This large increase in separation of the two ends suggests a complete displacement of the nonhybridized strand of the acceptor stem in the initiation complex.

Fluorescent Dyes↗

PubMed1999

Human Immunodeficiency Virus Reverse Transcriptase and Protease Sequence Database.

The HIV RT and Protease Sequence Database is an on-line relational database that catalogues evolutionary and drug-related human immunodeficiency virus reverse transcriptase (RT) and protease sequence variation (http://hivdb.stanford.edu). The database contains a compilation of nearly all published HIV RT and protease sequences including International Collaboration database submissions (e.g., GenBank) and sequences published in journal articles. Sequences are linked to data about the source of the sequence sample and the anti-HIV drug treatment history of the individual from whom the isolate was obtained. The database is curated and sequences are annotated with data from 180 literature references. Users can retrieve additional data and view alignments of sequences sets meeting specific criteria (e.g., treatment history, subtype, presence of a particular mutation).

Anti-HIV Agents↗

PubMed1999

Increased dependence of glucose production on peripheral insulin in diabetic depancreatized dogs.

We have recently found that in nondiabetic dogs and humans, suppression of glucose production (GP) is mediated by both peripheral and hepatic effects of insulin. We have also found that both nonesterified fatty acids (NEFA) and glucagon are important determinants of the peripheral effect of insulin on GP. However, in moderately hyperglycemic depancreatized dogs, suppression of GP appeared to be mediated by peripheral but not hepatic insulin. In this latter study, insulin concentrations were in the high postprandial range (approximately 300 pmol/L) and suppression of GP may have been close to maximum. The aim of the present study was to determine whether GP can be regulated by hepatic insulin in depancreatized dogs at low insulin concentrations in the postabsorptive range. Depancreatized dogs were maintained at moderately hyperglycemic levels (approximately 10 mmol/L) by subbasal insulin infusions. In paired experiments, additional low-dose equimolar insulin infusions (0.75 pmol/kg x min) were administered peripherally (PER, n = 6) or portally (POR, n = 6) during glucose clamps. This resulted in a minimal increase in peripheral insulin levels, which was greater in PER versus POR, 29.0 +/- 3.7 versus 11.7 +/- 2.2 pmol/L. Also, we infused insulin peripherally at half this rate (1/2 PER, n = 6) to match the increase in peripheral insulin levels in POR (1/2 PER, 14.6 +/- 2.2) and thus obtain a selective POR versus 1/2 PER difference in hepatic sinusoidal insulin levels. PER suppressed GP more than POR (45.4% +/- 4.0% v 35.3% +/- 6.8%, P < .001), whereas POR did not suppress GP more than 1/2 PER (35.6% +/- 6.3%). Therefore, suppression of GP was proportional to peripheral rather than hepatic sinusoidal insulin levels, as in our previous study at higher insulin concentrations. In conclusion, during glucose clamps in moderately hyperglycemic depancreatized dogs, (1) suppression of GP was dominated by insulin's peripheral effects not only at postprandial but also postabsorptive insulin levels, and (2) we found no evidence for a hepatic effect of insulin in suppressing GP. We hypothesize that this effect is reduced in the depancreatized dog model of diabetes due to hepatic insulin resistance and/or hyperglycemia.

Alanine↗

PubMed1999

Cloning of mouse prostaglandin transporter PGT cDNA: species-specific substrate affinities.

We recently identified and/or cloned the PG transporter PGT in the rat (rPGT) (Kanai, N., R. Lu, J. A. Satriano, Y. Bao, A. W. Wolkoff, and V. L. Schuster, Science 268: 866-869, 1995) and the human (hPGT) (Lu, R., and V. L. Schuster, J. Clin. Invest. 98: 1142-1149, 1996). Here we have cloned and expressed the mouse PGT (mPGT) cDNA. The tissue distribution of mPGT mRNA expression is significantly more restricted than that of rPGT and hPGT mRNA. Although the deduced amino acid sequence of mPGT is similar to the rat (91% identity) and human (82% identity) homologues, it has three regions of dissimilarity: amino acids 128-163 and 283-298, and valine 610 and isoleucine 611 (predicted to lie within putative transmembrane span 12). Affinities of hPGT, rPGT, and mPGT for several PG substrates differed, with hPGT having the highest [low Michaelis constant (K(m))] and mPGT the lowest affinity. A chimeric protein, linking the N-terminal domain of mPGT with the C-terminal domain of hPGT, had affinity for PGE2 indistinguishable from that of hPGT, indicating that the C-terminal domain dictates K(m). We mutagenized mouse valine 610 and isoleucine 611 to their corresponding human residues (methionine and glycine, respectively); however, these changes did not convert the inhibition constant of mPGT to that of hPGT. The mouse gene was localized to chromosome 9 in a region syntenic with the region of human chromosome 3 containing the hPGT gene. These studies highlight the species-dependence of tissue expression and function of PGT and lay the groundwork for the use of the mouse as a model system for the study of PGT function.

Amino Acid Sequence↗

PubMed1999

The effects of group size and group economic factors on collaboration: a study of the financial performance of rural hospitals in consortia.

STUDY QUESTIONS: To determine factors that distinguish effective rural hospital consortia from ineffective ones in terms of their ability to improve members' financial performance. Two questions in particular were addressed: (1) Do large consortia have a greater collective impact on their members? (2) Does a consortium's economic environment determine the degree of collective impact on members? DATA SOURCES AND STUDY SETTING: Based on the hospital survey conducted during February 1992 by the Robert Wood Johnson Hospital-Based Rural Health Care project of rural hospital consortia. The survey data were augmented with data from Medicare Cost Reports (1985-1991), AHA Annual Surveys (1985-1991), and other secondary data. STUDY DESIGN: Dependent variables were total operating profit, cost per adjusted admission, and revenue per adjusted admission. Control variables included degree of group formalization, degree of inequality of resources among members (group asymmetry), affiliation with other consortium group(s), individual economic environment, common hospital characteristics (bed size, ownership type, system affiliation, case mix, etc.), year (1985-1991), and census region dummies. PRINCIPAL FINDINGS: All dependent variables have a curvilinear association with group size. The optimum group size is somewhere in the neighborhood of 45. This reveals the benefits of collective action (i.e., scale economies and/or synergy effects) and the issue of complexity as group size increases. Across analyses, no strong evidence exists of group economic environment impacts, and the environmental influences come mainly from the local economy rather than from the group economy. CONCLUSION: There may be some success stories of collaboration among hospitals in consortia, and consortium effects vary across different collaborations. RELEVANCE/IMPACT: When studying consortia, it makes sense to develop a typology of groups based on some performance indicators. The results of this study imply that government, rural communities, and consortium staff and steering committees should forge the consortium concept by expanding membership in order to gain greater financial benefits for individual hospitals.

Cooperative Behavior↗

PubMed1999

Medicaid TEFRA option in Minnesota: implications for patient rights.

This research studied a special-needs population under age 18 who had both private insurance and Medicaid coverage through the Tax Equity and Fiscal Responsibility Act of 1982 (TEFRA) option. We found that children with managed care plans, particularly health maintenance organizations (HMOs), tended to incur higher total expenses to TEFRA than children with indemnity plans. Our findings also show that managed care in Minnesota tends to provide the same or marginally better coverage as indemnity plans do for core medical items but much less coverage for ancillary items such as home care, therapies, and durable medical equipment.

Adolescent↗

PubMed1999

American Society for Microbiology--99th general meeting. 30 May-3 June 1999, Chicago, IL, USA.

The American Society for Microbiology (ASM) celebrated its centenary at this meeting, which aimed to appeal to an audience with diverse microbiological interests. The program comprised six colloquia, division lectures and award sessions, division sessions, poster and special interest sessions, as well as pre-meeting workshops. The colloquia topics, selected by the ASM members advisory committee, were: pathogenesis; microbes and public health; microbial diversity; beyond the recombinant RNA revolution; molecular dissection of complex biological processes; and, host defenses. The divisional groups were: diagnostic microbiology and epidemiology; pathogenesis and host response mechanisms; general microbiology; and, molecular microbiology, physiology and virology. Each group highlighted a topic of importance to scientists from all divisions within that group and the divisional lecture was given by a distinguished scientist within one of the division's sessions.

Journal Article↗

PubMed1998

Effect of population-based interventions on laboratory utilization: a time-series analysis.

CONTEXT: Previous studies have identified methods of decreasing laboratory utilization. However, most were hospital-based, relatively small, single-centered, or of limited duration. OBJECTIVE: To determine the effect of 3 population-based interventions (physician guidelines, laboratory requisition form modification, and changes to funding policy) on laboratory utilization in Ontario. DESIGN: Interventional time-series analysis in which data analysis was based on all claims made to the Ontario Health Insurance Program between July 1, 1991, and April 1997 for laboratory tests affected by the interventions. SETTING: All clinical laboratories (not based in hospitals) in Ontario. INTERVENTIONS: Physician guidelines, modification of laboratory requisition form, and changes in funding policy for the use of the erythrocyte sedimentation rate test (ESR), microscopic urinalysis, tests for renal function, iron stores, serum urea, and serum iron determinations, and tests for thyroid dysfunction (total thyroxine and thyroid-stimulating hormone [TSH]). MAIN OUTCOME MEASURES: Change from 1991 to 1997 in utilization rates of ESR, microscopic urinalysis, serum urea and iron determinations, and tests for total thyroxine and TSH. RESULTS: Age- and sex-standardized rates for laboratory tests unaffected by the interventions were stable during the study period. Utilization of ESR and urea determination decreased by 58% (P<.001) and 57% (P<.001), respectively, after they were removed from the requisition form and guidelines discouraging their use were disseminated. Rates for urinalyses without microscopy increased by 1700% (P<.001), while microscopic urinalysis decreased by 14% (P<.001), after a policy change eliminated microscopic urinalysis from routine urinalysis. Rates of iron determination declined by 80% (P<.001) and ferritin rates increased by 34% (P= .05) when policy changes eliminated iron testing when ordered with ferritin and guidelines advocating ferritin alone for investigating iron deficiency were disseminated. Utilization of total thyroxine testing declined by 96% (P = .02) when the provincial health plan stopped its funding. When TSH was removed from the laboratory requisition form, a 12% decline (P= .03) in its use was observed. Through April 1997, these interventions saved more than 625000 tests or $210400. CONCLUSIONS: The combination of guideline dissemination, laboratory requisition form modification, and changes to funding policy was associated with significant reductions in laboratory utilization.

Clinical Laboratory Techniques↗

PubMed1998

Patterns of practice among older physicians in Ontario.

BACKGROUND: Policy-makers interested in the supply of doctors in Canada have recently begun focusing attention on older physicians. This study informs the policy debate by analysing the practice patterns of Ontario physicians aged 65 years and over. METHODS: A cross-sectional and longitudinal analysis of physician claims data for fiscal years 1989/90 through 1995/96 was conducted. The number of full-time equivalent (FTE) physicians by age category, urban or rural status, and specialty was calculated by means of an established method, and differences between older physicians, established physicians and recent graduates (in practice for 5 years or less), in terms of the types of services provided and patients seen, were examined. RESULTS: The proportion of FTE physicians aged 65 or more increased from 5.3% to 7.0% during the study period, whereas the proportion of recent graduates decreased from 19.6% to 16.3%. Of the older physicians, 61.4% practised part time (less than 1 FTE). Half of the physicians aged 75 in 1989/90 were still in practice 6 years later. Older physicians were less likely than those under age 65 to practice obstetrics (4.6% v. 16.9%), provide emergency department services (1.1% v. 14.8%) or house calls (38.7% v. 60.4%), or perform many minor procedures (38.7% v. 62.3%) (p < or = 0.001 for all comparisons). Older physicians tended to be male and had older patients in their practices than did younger physicians. Rural regions had higher proportions of older specialists. INTERPRETATION: Ontario's physician corps is aging. This may result in decreasing availability of obstetrics and emergency department coverage in the future. Encouraging retirement may create more openings for recent graduates, but if such policies are enacted, special attention should be paid to ensure that rural communities and older patients continue to be served.

Aged↗

PubMed1998

High-billing general practitioners and family physicians in Ontario: how do they do it? An analysis of practice patterns of GP/FPs with annual billings over $400,000.

BACKGROUND: To better understand the reasons why some fee-for-service physicians have high billing levels, the authors compared the practice and demographic characteristics of general practitioners and family physicians (GP/FPs) who submitted over $400,000 in annual Ontario Health Insurance Plan (OHIP) fee-for-service claims in 1994-95 with those of GP/FPs who billed between $35,000 and $400,000. METHODS: The authors describe the OHIP billing and physician characteristic data for fiscal year 1994-95. They used multivariate logistic regression to determine factors independently associated with high billing status. RESULTS: A total of 219 GP/FPs (2.5% of the GP/FPs in Ontario) billed over $400,000 in 1994-95. Of these, 14 had billing patterns similar to those of specialists, and 27 billed predominantly for diagnostic and therapeutic procedures (particularly physiotherapy). The remaining 178 (81.3%) billed for a mix of services similar to that of other GP/FPs but on average had 2.6 times the volume of patient assessments and a greater share of their total billings derived from diagnostic and therapeutic procedures (9.1% v. 5.6%). Multivariate analysis indicated that these high-volume GP/FPs were less likely than GP/FPs who billed between $35,000 and $400,000 to be 60 years of age or older (odds ratio [OR] 0.09, p < 0.05) and female (OR 0.21) and were more likely to be foreign graduates (OR 1.85) and practising in a region with low physician supply (OR 0.45 for each increase of 1 physician per 1000 population). Metropolitan Toronto was an outlier to the latter relation and was more likely to have high-volume GP/FPs (OR 16.89). INTERPRETATION: High-billing GP/FPs attained their high billing levels by maintaining large numbers of patient visits and by performing procedures. Further research is needed to determine the time spent per patient and the quality of care delivered by these physicians as well as the appropriateness of the procedures that they perform.

Adult↗

PubMed1998

Fee code creep among general practitioners and family physicians in Ontario: why does the ratio of intermediate to minor assessments keep climbing?

BACKGROUND: "Fee code creep" is the increasing tendency of primary care physicians in Ontario to bill for more intermediate than minor assessments over time. The authors examine the extent and nature of fee code creep and describe physician characteristics associated with the changes. METHODS: A cross-sectional and longitudinal analysis of Ontario Health Insurance Plan billing and physician characteristic data was conducted for fee-for-service general practitioners and family physicians (GP/FPs) in Ontario. The ratio of intermediate to minor assessments (I-M ratio) was determined for the period 1978-79 to 1994-95, and the relation of various physician characteristics to high ratios was tested with bivariate and multivariate analysis. RESULTS: The I-M ratio rose 10-fold, from 0.3 in 1978-79 to 2.9 in 1994-95. Although the I-M ratio was higher for older patients and young children, changes in population age profile over time did not account for any of the increase. The median ratio varied widely among groups of physicians: urban physicians had higher ratios than rural ones (3.9 v. 3.0, p < 0.05), and recent graduates had higher ratios than physicians 60 years of age or older (5.1 v. 2.9, p < 0.05). The I-M ratio was inversely related to number of visits; physicians billing for fewer than 5000 visits had a median ratio of 4.2, whereas those billing for 20,000 visits or more had a median ratio of 1.6. INTERPRETATION: Fee code creep has contributed to expenditure growth in Ontario. This phenomenon was related to both an increase in I-M ratio over time among physicians practising throughout the study period and an influx of new physicians billing at a higher ratio. Creep was not the result of aging of the population.

Adult↗