Physician Billing Research Articles

Effects of Outpatient Aftercare on Psychiatric Rehospitalization Among Children and Emerging Adults in Alberta, Canada.

The one-year readmission rates for children and youths hospitalized for a psychiatric condition is estimated at 38%. Studies suggest that these high readmission rates result from a lack of aftercare, but evidence is mixed. This study further explored the relationship between aftercare and readmission among children and youths ages five to 24 in Alberta, Canada, by using the same study sample to identify predictors of both outcomes. A retrospective analysis using linked administrative data was performed. Records of the index inpatient stay and any subsequent readmissions for a mental health reason between July 1, 2007, and December 31, 2012, were obtained from the Discharge Abstract Database. Data on outpatient aftercare for this sample were obtained from ambulatory care records and a patient-level physician billing database. Rates of aftercare and readmission were calculated. A Cox proportional hazards regression model was used to identify predictors of both outcomes. Overall, 15,628 hospitalizations were identified for 12,728 unique individuals. For these hospitalizations, aftercare services were recorded for 29.4% within one week of discharge and for 54.5% within 30 days. Fourteen percent of hospitalizations resulted in readmission within 90 days. Aftercare was associated with a 32% reduction in readmission. Prior service use, longer hospital stays, higher income, specific diagnoses, female sex, and comorbid mental health conditions were associated with a greater likelihood of aftercare receipt. Access to community mental health services for children and youths remains a priority. The significant role of aftercare in reducing readmission risk demonstrates the need to improve these services.

Modifying the Primary Care Exception Rule to Require Competency-Based Assessment.

Teaching residents to practice independently is a core objective of graduate medical education (GME). However, billing rules established by the Centers for Medicare and Medicaid Services (CMS) require that teaching physicians physically be present in the examination room for the care they bill, unless the training program qualifies for the Primary Care Exception Rule (PCER). Teaching physicians in programs that use this exception can bill for indirectly supervised ambulatory care once the resident who provides that care has completed six months of training. However, CMS does not mandate that programs assess or attest to residents' clinical competence before using this rule. By requiring this six-month probationary period, the implication is that residents are adequately prepared for indirectly supervised practice by this time. As residents' skill development varies, this may or may not be true. The PCER makes no attempt to delineate how residents' competence should be assessed, nor does the GME community have a standard for how and when to make this assessment specifically for the purpose of determining residents' readiness for indirectly supervised primary care practice.In this Perspective, the authors review the history and current requirements of the PCER, explore its limitations, and offer suggestions for how to modify the teaching physician billing requirements to mandate the evaluation of residents' competence using the existing milestones framework. They also recommend strategies to standardize this process of evaluation and to develop benchmarks across training programs.

Diagnostic Accuracy of Transient Ischemic Attack from Physician Claims.

Hospitalization data underestimate the occurrence of transient ischemic attack (TIA). As TIA is frequently diagnosed in primary care, methodologies for the accurate ascertainment of a TIA from physician claims data are required for surveillance and health systems planning in this population. The present study evaluated the diagnostic accuracy of multiple algorithms for TIA from a longitudinal population-based physician billing database. Population-based administrative data from the province of British Columbia were used to identify the base population (1992-2007; N=102,492). Using discharge records for hospital admissions for acute ischemic stroke with a recent (<90 days) TIA as the reference standard, we performed receiver-operating characteristic analyses to calculate sensitivity, specificity, positive and negative predictive values and overall accuracy, and to compare area under the curve for each physician billing algorithm. To evaluate the impact of different case definitions on population-based TIA burden, we also estimated the annual TIA occurrence associated with each algorithm. Physician billing algorithms showed low to moderate sensitivity, with the algorithm for two consecutive physician visits within 90 days showing the highest sensitivity at 37.7% (CI 95%=37.4-38.1). All algorithms demonstrated high specificity and moderate to high overall accuracy, resulting in low positive predictive values (≤5%), low discriminability (0.53-0.57) and high false positive rates (1 - specificity). Population-based estimates of TIA occurrence were comparable to prior studies and declined over time. Physician billing data have insufficient sensitivity to identify TIAs but may be used in combination with hospital discharge data to improve the accuracy of estimating the population-based occurrence of TIAs.

Heart Disease, Hypertension, Gestational Diabetes Mellitus, and Preeclampsia/Eclampsia in Mothers With Juvenile Arthritis: A Nested Case-Control Study.

To determine whether women with a history of juvenile arthritis are at higher risk for heart disease and hypertension and for developing adverse maternal outcomes: gestational diabetes mellitus, maternal hypertension, and preeclampsia/eclampsia. We designed a nested case-control study from a cohort of first-time mothers with prior physician billing codes suggesting juvenile arthritis, and a matched comparison group without juvenile arthritis. For the nested case-control design, we selected 3 controls for each case for the outcomes of heart disease (n = 403), prepregnancy hypertension (n = 66), gestational diabetes mellitus (n = 285), maternal hypertension (n = 561), and preeclampsia/eclampsia (n = 236). We used conditional logistic regression, adjusting for maternal age and education. Having juvenile arthritis was associated with heart disease (odds ratio [OR] 2.44 [95% confidence interval (95% CI) 1.15-5.15]) but not with gestational hypertension, diabetes mellitus, or preeclampsia/eclampsia. All 66 cases of prepregnancy hypertension had juvenile arthritis. Having prepregnancy hypertension was strongly associated with preeclampsia/eclampsia (OR 8.05 [95% CI 2.69-24.07]). Women with a history of juvenile arthritis had a higher risk of heart disease. This risk signals the potential importance of cardiac prevention strategies in juvenile arthritis. As this was a retrospective study, it was not possible to correct for some relevant potential confounders. Further studies should assess the impact of medications, disease severity, and other factors (e.g., obesity) on cardiac outcomes in juvenile arthritis.

Factors associated with mode of colorectal cancer detection and time to diagnosis: a population level study

BackgroundAlthough it is well-known that early detection of colorectal cancer (CRC) is important for optimal patient survival, the relationship of patient and health system factors with delayed diagnosis are unclear. The purpose of this study was to identify the demographic, clinical and healthcare factors related to mode of CRC detection and length of the diagnostic interval.MethodsAll residents of Alberta, Canada diagnosed with first-ever incident CRC in years 2004–2010 were identified from the Alberta Cancer Registry. Population-based administrative health datasets, including hospital discharge abstract, ambulatory care classification system and physician billing data, were used to identify healthcare services related to CRC diagnosis. The time to diagnosis was defined as the time from the first CRC-related healthcare visit to the date of CRC diagnosis. Mode of CRC detection was classified into three groups: urgent, screen-detected and symptomatic. Quantile regression was performed to assess factors associated with time to diagnosis.Results9626 patients were included in the study; 25% of patients presented as urgent, 32% were screen-detected and 43% were symptomatic. The median time to diagnosis for urgent, screen-detected and symptomatic patients were 6 days (interquartile range (IQR) 2–14 days), 74 days (IQR 36–183 days), 84 days (IQR 39–223 days), respectively. Time to diagnosis was greater than 6 months for 27% of non-urgent patients. Healthcare factors had the largest impact on time to diagnosis: 3 or more visits to a GP increased the median by 140 days whereas 2 or more visits to a GI-specialist increased it by 108 days compared to 0–1 visits to a GP or GI-specialist, respectively.ConclusionA large proportion of CRC patients required urgent work-up or had to wait more than 6 months for diagnosis. Actions are needed to reduce the frequency of urgent presentation as well as improve the timeliness of diagnosis. Findings suggest a need to improve coordination of care across multiple providers.

Use of MRSA Nasal Swab to Guide Empiric Antibiotic Treatment of Hospital Acquired or Community Acquired Pneumonia in a Pediatric Population

BackgroundCurrent PIDS/IDSA guidelines recommend the use of MRSA empiric coverage in the case of hospital acquired pneumonia (HAP) and in community acquired pneumonia (CAP) if patients have risk factors or clinical characteristics consistent with MRSA infection. Retrospective studies in adult patients have shown the MRSA PCR nasal swab to have a negative predictive value of 99% in patients treated for pneumonia in the inpatient setting, making the MRSA nasal swab a potential tool to guide de-escalation of empiric antibiotics. No published studies to date have examined the sensitivity and specificity of MRSA PCR nasal swab in pediatric populationsMethodsA cohort of patients was identified by cross-matching internal physician and laboratory billing data from the past 10 years at IU hospitals in the Indianapolis area for pneumonia. An initial pool of 550 patients were identified. Patients less than 25 years of age were eligible. Patients were excluded if they had medical conditions such as Cystic Fibrosis, Chronic Lung Disease, or cavitary pneumonia seondary to IV drug use. Chart review identified a total of 28 patients that met diagnostic criteria for pneumonia, had culture data and had a MRSA PCR nasal swab performed during treatment.ResultsIn the cohort, 5 patients had positive MRSA nasal swab and positive cultures for MRSA. Two patients had positive MRSA swab with negative cultures. Twenty-one patients had negative MRSA nasal swabs and cultures without MRSA growth. No patients were identified with a negative MRSA nasal swab that grew MRSA in cultures. In this population the MRSA nasal swab had a sensitivity of 100%, specificity of 91%, positive predictive valve of 71%, and a negative predictive value of 100%. The patients with negative MRSA swab and negative cultures, 66% were treated with vancomycin. If MRSA nasal PCR was used to guide treatment, 71% of the patients with a negative nasal swab had potential to discontinue MRSA empiric antibiotics sooner.ConclusionThe MRSA PCR nasal swab has a high negative predictive valve in this pediatric population of inpatients treated for HAP/CAP. This is consistent with results from adult studies. The high negative predictive valve makes the MRSA PCR nasal swab a potential tool as a rapid diagnostic test to guide empiric antibiotic therapy.Disclosures All authors: No reported disclosures.

Effectiveness of Influenza Vaccine in Preventing Death among Ontario Residents Aged ≥65 Years during 20 Seasons

BackgroundEstimation of influenza vaccine effectiveness (VE) among older adults at high risk of serious complications of influenza infection is challenging. These challenges include identifying and adjusting for potential confounders. The rarity of documented influenza deaths, even among individuals at greatest risk, makes VE assessment for this outcome particularly difficult. Thus, population-level linkages of public health system records are helpful in estimating VE for preventing death.MethodsWe conducted a retrospective cohort study from 1993 through 2013 among community-dwelling residents of Ontario aged ≥65 years. Eligible subjects were registered with Ontario’s publicly funded health insurance program, which provided universal, free access to physician services, hospital care, and vaccines; we excluded those with no contact with the health system during the prior 3 years. We assessed influenza VE for preventing death from any cause and death for which the primary cause was a respiratory or circulatory condition. Influenza vaccination was determined using physician and pharmacist billing claims. Temperature and influenza virus detection data were collected from provincial sources. Ratio-of-ratios models were used to estimate VE, by comparing marginal changes in outcome rates among vaccinated and unvaccinated groups at various levels of influenza circulation. We evaluated several methods of characterizing temporal variation in influenza circulation and several geographic scales for using influenza and temperature data in VE estimation models.ResultsDuring the 20-year study period, we estimated VE among a mean of 1.39 million subjects each season, of whom a mean of 51.9% were vaccinated. During weeks of high influenza A circulation, we estimated that VE for the prevention of any death was 16% (95% CI -6% to 38%) and for the prevention of a respiratory or circulatory death was 21% (95% CI 2% to 40%). The precision of VE estimates improved when regional-level rather than Ontario-wide temperature data were used.ConclusionDuring weeks of influenza A circulation over 20 seasons, we found that modest but significant reductions in deaths with an underlying respiratory or circulatory cause occurred among Ontario residents aged ≥65 who received an influenza vaccine.Disclosures All authors: No reported disclosures.

Relative Risk and Incidence for Developmental Dysplasia of the Hip

To determine the incidence and associated risk factors of developmental dysplasia of the hip (DDH) in a modern population without universal screening. Children with DDH were identified from the Manitoba Centre for Health Policy's Data Repository by the use of International Classification of Diseases diagnosis codes as well as physician billing tariffs for surgical procedures for DDH for all children born between 1995 and 2012. To identify the outpatient-treated patients, ultrasound scans and radiographic imaging for DDH were reviewed for 2004-2012. Overall incidence was calculated on the basis of birth rate for the province per year. Relative risks of sex, first born, breech position, clubfoot deformity, multiple gestations, as well as regional health areas were analyzed with χ2 tests. We identified 1716 cases of DDH of 258 499 newborns. The incidence of DDH was calculated at 6.6/1000 newborns. Late-presenting DDH was detected in 2.2/1000 newborns. Female first-born children, clubfoot deformity, and breech position were associated significantly with an increased risk. Children with DDH born in rural areas of the Northern and Central part of Manitoba presented at a later age than those who are born in the urban areas (P < .0001) CONCLUSION: This study shows the need for improved early detection and awareness at well-baby clinics of risk factors and regional differences for DDH.

Vasectomy and risk of prostate cancer: population based matched cohort study

Objective To determine the association between vasectomy and prostate cancer, adjusting for measures of health seeking behaviour.Design Population based matched cohort study.Setting Multiple validated healthcare databases in Ontario, Canada, 1994-2012.Participants...

Predicting tuberculosis risk in the foreign-born population of British Columbia, Canada: study protocol for a retrospective population-based cohort study

IntroductionImproved understanding of risk factors for developing active tuberculosis (TB) will better inform decisions about diagnostic testing and treatment for latent TB infection (LTBI) in migrant populations in low-incidence regions....

Validity of administrative data for identification of obstructive sleep apnea.

Obstructive sleep apnea (OSA) is a common condition associated with significant morbidity and health-care utilization. We determined the validity of an algorithm derived from administrative data for identifying OSA using the respiratory disturbance index (RDI) as the reference standard. We conducted a retrospective cohort study of adults in Alberta, Canada referred for facility and community-based sleep diagnostic testing between July 2005 and August 2007. Validity indices were estimated for several case definitions of OSA derived from outpatient physician billing claims and hospital discharge codes. For each algorithm, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated against several reference standards for OSA (RDI≥5h-1 , RDI≥15h-1 or RDI≥30h-1 ). For the 2149 patients included in the study, an algorithm requiring one hospital discharge code or two outpatient billing claims identifying OSA in a 2-year period had a sensitivity of 24.1%, specificity of 67.8%, PPV of 74.8% and NPV of 18.3% (reference standard RDI≥5h-1 ). When comorbidities were included in the case definition, the specificity was 90.5% and PPV was 83.3% (reference standard RDI≥5h-1 ). Similar findings were observed using RDI≥15 h-1 and ≥30h-1 as the reference standard. We identify a claims-based algorithm that identifies OSA with a high degree of specificityin patients referred for sleep diagnostic testing. This validatedalgorithm has a good PPV and may be useful when identifying patients with OSA for population studies within a single-payer health-care system.

How Reliable Are Administrative Data for Capturing Stroke Patients and Their Care

Background/Aims: The reliability of diagnostic coding of acute stroke and transient ischemic attack (TIA) in administrative data is uncertain. The purpose of this study is to determine the agreement between administrative data sources and chart audit for the identification of stroke type, stroke risk factors, and the use of hospital-based diagnostic procedures in patients with stroke or TIA. Methods: Medical charts for a population-based sample of patients (n = 14,508) with ischemic stroke, intracerebral hemorrhage (ICH), or TIA discharged from inpatient and emergency departments (ED) in Ontario, Canada, between April 1, 2012 and March 31, 2013, were audited by trained abstractors. Audited data were linked and compared with hospital administrative data and physician billing data. The positive predictive value (PPV) of hospital administrative data and kappa agreement for the reporting of stroke type were calculated. Kappa agreement was also determined for stroke risk factors and for select stroke-related procedures. Results: The PPV for stroke type in inpatient administrative data ranged from 89.5% (95% CI 88.0-91.0) for TIA, 91.9% (95% CI 90.2-93.5) for ICH, and 97.3% (95% CI 96.9-97.7) for ischemic stroke. For ED administrative data, PPV varied from 78.8% (95% CI 76.3-81.2) for ischemic, 86.3% (95% CI 76.8-95.7) for ICH, and 95.3% (95% CI 94.6-96.0) for TIA. The chance-corrected agreement between the audited and administrative data was good for atrial fibrillation (k = 0.60) and very good for diabetes (k = 0.86). Hospital administrative data combined with physician billing data more than doubled the observed agreement for carotid imaging (k = 0.65) and echocardiography (k = 0.66) compared to hospital administrative data alone. Conclusions: Inpatient and ED administrative data were found to be reliable in the reporting of the International Classification of Diagnosis, 10th revision, Canada (ICD-10-CA)-coded ischemic stroke, ICH and TIA, and for the recording of atrial fibrillation and diabetes. The combination of physician billing data with hospital administrative data greatly improved the capture of some diagnostic services provided to inpatients.

What “big population data” tells us about neurological disorders comorbidity

Objective: To use a large population dataset to examine neurological disorder comorbidity. Seventeen main classes of Diagnosed International Classification of Disease (ICD) disorder codes were grouped and compared to ICD-9 Nerurological disorder codes.Methods: Calgary, Alberta, health zone diagnosis, sex and age data from 1994-2009 physician billings (n = 763,449) were grouped and tallied on the basis of the presence or absence of any neurological disorder across the 17 remaining ICD main disorder classes and represented as odds ratios (ORs with 95% confidence intervals).Results: Within the ICD categories the 17 classes were ranked by ORs: Ill-defined conditions (OR 7.42), musculoskeletal and connective tissue system disorders (OR 4.22), and psychiatric disorders (OR 3.81) were the ranked the highest main classes, respectively. Thirteen additonal main classes had ORs greaeter than 2.00.Conclusions: There was a strong relationship between neurological disorders and the ICD main classes. The results of this broad stroke analysis point to the requirement for analysis of the both the temporal relationships (e.g., before vs. after) between neurological disorders and comorbid disorderss as well as more fine-grained description of the specifice intra-class disorders underlying the reported odds ratios.

Cost analysis of iliac stenting performed in the operating room and the catheterization lab: A case-control study

BackgroundIliac arterial stenting is performed both in the operating room (OR) and the catheterization lab (CL). To date, no analysis has compared resource utilization between these locations. MethodsConsecutive patients (n = 105) treated at a single center were retrospectively analyzed. Patients included adults with chronic, symptomatic iliac artery stenosis with a minimum Rutherford classification (RC) of 3, treated with stents. Exclusion criteria were prior stenting, acute ischemia, or major concomitant procedures. Immediate and two-year outcomes were observed. Patient demographics, perioperative details, physician billings, and hospital costs were recorded. Multivariable regression was used to adjust costs by patient and perioperative cost drivers. ResultsFifty-one procedures (49%) were performed in the OR and 54 (51%) in the CL. Mean age was 57, and 44% were female. Severe cases were more often performed in the OR (RC ≥ 4; 42% vs. 11%, P < 0.001) and were associated with increased total costs (P < 0.01). OR procedures more often utilized additional stents (stents ≥ 2; 61% vs. 46%, P = 0.214), thrombolysis (12% vs. 0%, P = 0.011), cut-down approach (8% vs. 0%, P = 0.052), and general anesthesia (80% vs. 0%, P < 0.001): these were all associated with increased costs (P < 0.05). After multivariable regression, location was not a predictor of procedure room or total costs but was associated with increased professional fees. Same-stay (5%) and post-discharge reintervention (33%) did not vary by location. ConclusionsThe OR was associated with increased length of stay, more ICU admissions, and increased total costs. However, OR patients had more severe disease and therefore often required more aggressive intervention. After controlling for these differences, procedure venue per se was not associated with increased costs, but OR cases incurred increased professional fees due to dual-provider charges. Given the similar clinical results between venues, it seems reasonable to perform most stenting in the CL or utilize conscious sedation in the OR.

Province-Wide Review of Pediatric Shiga Toxin-Producing Escherichia coli Case Management

To identify the gaps in the care of children infected with Shiga toxin-producing Escherichia coli (STEC), we sought to quantitate care received and management timelines. Such knowledge is crucial to the design of interventions to prevent the development of hemolytic uremic syndrome (HUS). We conducted a retrospective case-series study of 78 children infected with STEC in Alberta, Canada, through the linkage of microbiology and laboratory results, telephone health advice records, hospital charts, physician billing submissions, and outpatient antimicrobial dispensing databases. Outcomes were the time intervals between initial presentation and reporting of positive culture result and symptom onset to HUS and to describe the proportions that had baseline blood work performed and received antibiotics. Seventy-eight children infected with STEC were identified; 13% (10/78) developed HUS. Median time from initial presentation to laboratory stool sample receipt was 33 hours (IQR 18, 42); time to positive culture was 120 hours (IQR 86, 205). Time from symptom onset to HUS diagnosis was 188 ± 37 hours. Baseline blood tests were obtained in 74% (58/78) of infected children. Antibiotics were administered to 50% (5/10) of those who developed HUS and 22% (15/78) of those who did not; P = .11. The provincial telephone advice system received 31 calls regarding 24 children infected with STEC; 23% (7/31) of callers were recommended to seek emergency department care. A significant proportion of children developed HUS following multiple interactions with the health care system. Delays in the confirmation of STEC infection occurred. There are numerous opportunities to improve the timing, monitoring, and interventions in children infected with STEC.

Clinical Impact of Subsequent Depression in Patients With a New Diagnosis of Stable Angina: A Population-Based Study.

Depression is prevalent among patients with myocardial infarction and is associated with a worse prognosis. However, little is known about its importance in patients with chronic stable angina. We conducted a retrospective population-based cohort study to determine the occurrence and predictors of developing depression in patients with a new diagnosis of chronic stable angina. In addition, we sought to understand its impact on subsequent clinical outcomes. Our cohort included patients in Ontario, Canada, with stable angina based on obstructive coronary artery disease found on angiogram. Depression was ascertained by physician billing codes and hospital admissions diagnostic codes. We first developed multivariable Cox proportional hazards models to determine predictors of developing depression. Clinical outcomes of interest included all-cause mortality, admission for myocardial infarction, and subsequent revascularization. Using hierarchical multivariable Cox proportional hazards models with occurrence of depression as a time-varying variable to control for potential immortal time bias, we evaluated the impact of depression on clinical outcomes. Our cohort consisted of 22 917 patients. The occurrence of depression after diagnosis of stable chronic angina was 18.8% over a mean follow-up of 1084 days. Predictors of depression included remote history of depression, female sex, and more symptomatic angina based on Canadian Cardiovascular Society class. Patients who developed depression had a higher risk of death (hazard ratio 1.83, 95% confidence interval 1.62-2.07) and admission for myocardial infarction (hazard ratio 1.36, 95% confidence interval 1.10-1.67) compared with nondepressed patients. Depression is common in patients with chronic stable angina and is associated with increased morbidity and mortality.

Using physician billing claims from the Ontario Health Insurance Plan to determine individual influenza vaccination status: an updated validation study.

Owing to the absence of a vaccination registry in Ontario, administrative data are currently the best available source to determine population-based individual-level influenza vaccination status. Our objective was to validate physician billing claims for influenza vaccination in the Ontario Health Insurance Plan database against the Canadian Community Health Survey. We used self-reported seasonal influenza vaccination status of Ontario residents surveyed between 2007 and 2009 as the reference standard. The survey responses were linked to physician claims database records to validate billing codes for influenza vaccination. We calculated sensitivity, specificity, positive predictive value and negative predictive value with 95% confidence intervals (CIs). We stratified the data by several covariates and comorbidities to determine stratum-specific performance characteristics. We used these estimates to adjust an estimate of influenza vaccine effectiveness for the 2010/11 influenza season. For the 47 301 patients included in the analysis, the sensitivity for the billing codes was 49.8% (95% CI 49.0%-50.5%), specificity was 95.7% (95% CI 95.5%-96.0%), positive predictive value was 88.4% (95% CI 87.8%-89.0%) and negative predictive value was 74.5% (95% CI 74.0%-74.9%). Performance measures were optimized in patients aged 65 years and older, particularly those with comorbidities. Although administrative data have limitations for determining influenza vaccination status, owing to the high positive predictive value, they are well suited for self-controlled study designs that are often used to assess vaccine safety. For studies of coverage and effectiveness, restricting the cohort to patients aged 65 years and older will minimize misclassification bias. Performance characteristics from this study can be used to mitigate misclassification bias.

Utilization of Ambulatory Physician Encounters, Emergency Room Visits, and Hospitalizations by Systemic Lupus Erythematosus Patients: A 13-Year Population Health Study.

To determine total physician encounters, emergency room (ER) visits, and hospitalizations in an incident cohort of systemic lupus erythematosus (SLE) cases and matched control patients over 13 years. A retrospective cohort study was performed utilizing administrative health care data from approximately 1 million people with access to universal health care. Using International Classification of Diseases, Ninth and Tenth Revisions diagnostic codes, 7 SLE case definitions were used. Each case was matched by age and sex to 4 randomly selected controls. Data included physician billings, ER visits, and hospital discharges over 13 years. The number of incident SLE cases varied from 564 to 4,494 depending on the case definition used. The mean age varied from 47.7 to 50.6 years and the proportion of females from 78.0% to 85.1%. SLE utilization of physicians was highest in the index year, and declined significantly thereafter for all case definitions. By the fourth year, encounters with subspecialty physicians fell by 60% (rheumatologists), 50% (internists), and 31% (other physicians). In contrast, visits to family physicians fell by only 9%. Visits to the ER and hospital admissions for SLE cases were also more frequent early in the disease course and fell significantly over the study for both ER visits (all case definitions) and hospitalizations (2 of 7 case definitions). In SLE patients, health care utilization is highest in the first few years following the diagnosis, which is also the time of maximal involvement by rheumatologists. Utilization declines over time, and encounters with patients' family physicians predominate over those of other physician groups.

Association of erythropoiesis-stimulating agents and the incidence risk of cancer diagnosis among chronic dialysis patients: a nested case-control study.

Erythropoiesis-stimulating agents (ESAs) are the cornerstone of the treatment for anemia in end-stage renal disease (ESRD) patients. Although a correlation has been established between ESAs and increased tumor growth among patients with cancer-related anemia, an association with a higher incidence of cancer among chronic dialysis patients remains relatively unclear. We completed a nested case-control study in a cohort of 4574 patients who began chronic dialysis treatment between 1 January 2001 and 31 December 2007 in Quebec, Canada, utilizing dialysis registry and administrative databases exclusively to extract our data. We excluded patients with a prior diagnosis of cancer. Eligible cases were identified by the time of initial cancer diagnosis obtained from either the hospital's discharge or physician billing form. We then randomly selected up to 10 controls for each case. ESA exposure was evaluated between 6 and 9 months prior to the initial cancer diagnosis. The mean weekly exposure was used to categorize ESA usage as either a low dose (<30 µg/week), moderate dose (30-70 µg/week) or high dose (>70 µg/week). We estimated the association between ESAs and the risk of developing cancer using a multivariable conditional logistic regression. We identified 419 cases of cancer and 3895 matched controls during the study period. The use of ESAs was associated with a higher risk of cancer {odds ratio [OR] 1.04 [95% confidence interval (CI) 1.02-1.07]}. Specifically, patients in the high exposure group (>70 µg/week) had an increased risk of developing cancer [OR 1.77 (95% CI 1.18-2.66)] compared with patients in the unexposed group. High-dose ESA was associated with an increased incidence risk of new cancer diagnosis among chronic dialysis patients.

On Adjusting for Life's Confounding.

A wide range of data sources are available to study the epidemiology of mental illness. Community surveys such as Alex Leighton’s Stirling County Study are the gold standard for such data sources, particularly because community surveys cover everyone, not just people seeking treatment. However, as surveys require a lot of resources, other methods are also used, each of which has strengths and weaknesses. For example, medical records contain detailed information, but this can be difficult to extract and the quality may vary. Another source entails administrative data, typically hospital separations, physician billings, ambulatory care visits, and drug databases. While such data require careful analysis with the use of multivariate or propensity score techniques to adjust for potential confounding variables, these data can be invaluable in the study of diseases with multifactorial aetiologies.