Implications of conducting trend analyses of emergency department visits using publicly released masked design variables.


STUDY OBJECTIVE:We examine whether using public National Hospital Ambulatory Medical Care Survey (NHAMCS) data with masked design variables produces different estimates, standard errors, and confidence intervals (CIs) for the temporal trend of overall and injury-related emergency department (ED) visits compared with using unmasked data housed at the Centers for Disease Control and Prevention. METHODS:We obtained counts of ED visits with their standard errors for unmasked data from published summaries from 1999 through 2006. Public files with masked design variables were used to estimate visit counts and rates with standard errors for each year, using the Taylor series linearization method. Weighted least squares linear regressions were used for trend analysis to estimate the annual change in visits. RESULTS:Compared with using unmasked data, using masked data produced similar estimates of overall ED visit counts and rates for each year from 1999 through 2006 but overestimated standard errors by 27% on average (range 12% to 45%). According to unmasked data, overall ED visit counts increased by 1.973 million annually (standard error 0.747; 95% CI 0.505 to 3.440 million [corrected] ). With masked data, the estimated change was 1.977 million visits annually (standard error 0.894; 95% CI -0.221 to 3.733 million [corrected] ). As for injury-related ED visit counts, masked data overestimated the standard error by 16% for trend. Although neither unmasked nor masked data suggested a statistically significant annual increase of overall or injury-related ED visit rate, masked data overestimated the standard error by 16%. CONCLUSION:Using masked public data overestimated standard errors for trend of counts and rates for overall and injury-related ED visits and resulted in wider CIs.


Ann Emerg Med


Zhu M,Chu H,Rice TM,Carter MW




Has Abstract


2011-06-01 00:00:00














  • Video capsule endoscopy in the emergency department: a prospective study of acute upper gastrointestinal hemorrhage.

    abstract:STUDY OBJECTIVE:Video capsule endoscopy has been used to diagnose gastrointestinal hemorrhage and other small bowel diseases but has not been tested in an emergency department (ED) setting. The objectives in this pilot study are to demonstrate the ability of emergency physicians to detect blood in the upper gastrointes...

    journal_title:Annals of emergency medicine

    pub_type: 临床试验,杂志文章


    authors: Meltzer AC,Ali MA,Kresiberg RB,Patel G,Smith JP,Pines JM,Fleischer DE

    更新日期:2013-04-01 00:00:00

  • Electric shock does not save snakebitten rats.

    abstract::A team of missionary doctors from Ecuador recently described striking success in the treatment of venomous snakebites with a series of brief, high-voltage, low-current electric shocks applied to the bit site. We designed a randomized, controlled, blinded test of their methods in laboratory rats. Venom of the fer-de-la...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Howe NR,Meisenheimer JL Jr

    更新日期:1988-03-01 00:00:00

  • Serum levels of smooth muscle heavy-chain myosin in patients with ectopic pregnancy.

    abstract:STUDY OBJECTIVE:Previous studies have suggested that serum markers of smooth muscle destruction have utility in predicting ectopic pregnancy. Our goal was to determine whether a novel marker of muscle destruction, smooth muscle heavy-chain myosin (SMHC), is elevated in the serum of patients with ectopic pregnancy. MET...

    journal_title:Annals of emergency medicine

    pub_type: 临床试验,杂志文章


    authors: Birkhahn RH,Gaeta TJ,Suzuki T,Katoh H,Nagai R,Bove J

    更新日期:2000-08-01 00:00:00

  • Significance of symptoms and signs in patients with traumatic aortic rupture.

    abstract::The records of 50 patients with traumatic aortic rupture (Group I) and 50 patients with blunt chest trauma but negative aortograms (Group II) were reviewed retrospectively. Symptoms and signs referable to the chest and thoracic aorta were recorded and compared in Group I and Group II patients. Each patient's chart was...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Sturm JT,Perry JF Jr,Olson FR,Cicero JJ

    更新日期:1984-10-01 00:00:00

  • Epidemiology and practice of emergency medicine in a developing country.

    abstract:STUDY OBJECTIVE:To analyze the emergency medicine system in a developing country and identify areas of need and potential collaboration. DESIGN:Convenience sample surveys of all emergency visits over a 2-week period, hospital admission and health department statistics, and interviews with government officials, health ...

    journal_title:Annals of emergency medicine

    pub_type: 评论,杂志文章


    authors: Kirsch TD,Hilwig WK,Holder Y,Smith GS,Pooran S,Edwards R

    更新日期:1995-09-01 00:00:00

  • Opiate antagonist in traumatic shock.

    abstract::In experimental animal studies, opiate receptor antagonists (such as naloxone) and physiological opiate antagonists (thyrotropin-releasing hormone [TRH] have been used with some success to improve outcome and physiological variables following traumatic shock associated with hypovolemia, spinal cord trauma, and head in...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章,评审


    authors: McIntosh TK,Faden AI

    更新日期:1986-12-01 00:00:00

  • Randomized Trial of Intravenous Lidocaine Versus Hydromorphone for Acute Abdominal Pain in the Emergency Department.

    abstract:STUDY OBJECTIVE:We compare the efficacy and safety of intravenous lidocaine with that of hydromorphone for the treatment of acute abdominal pain in the emergency department (ED). METHODS:This was a randomized, double-blind, clinical trial conducted in 2 EDs in the Bronx, NY. Adults weighing 60 to 120 kg were randomize...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章,随机对照试验


    authors: Chinn E,Friedman BW,Naeem F,Irizarry E,Afrifa F,Zias E,Jones MP,Pearlman S,Chertoff A,Wollowitz A,Gallagher EJ

    更新日期:2019-08-01 00:00:00

  • Determination of cerebral cortical blood flow: a thermal technique.

    abstract::A mathematical model for tissue thermodilution was developed to study cerebral cortical perfusion before and after controlled perfusion arrest. Cerebral cortical perfusion rates are readily determined by this method. A thermistor was introduced into the subdural space and secured in direct contact with the frontal cor...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Hoehner PJ,Krause GS,White BC,Gadzinski DS

    更新日期:1983-01-01 00:00:00

  • Cardiac arrest witnessed by prehospital personnel: intersystem variation in initial rhythm as a basis for a proposed extension of the Utstein recommendations.

    abstract:STUDY OBJECTIVE:To test the hypothesis that intersystem variation in initial rhythm among EMS-witnessed arrests is of sufficient magnitude to warrant standardization of survival by creation of an Utstein-style denominator of EMS-witnessed ventricular fibrillation (VF). METHODS:We conducted a planned subset analysis of...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Gallagher EJ,Lombardi G,Gennis P

    更新日期:1997-07-01 00:00:00

  • Observational studies of patients in the emergency department: a comparison of 4 sampling methods.

    abstract:STUDY OBJECTIVE:We evaluate the ability of 4 sampling methods to generate representative samples of the emergency department (ED) population. METHODS:We analyzed the electronic records of 21,662 consecutive patient visits at an urban, academic ED. From this population, we simulated different models of study recruitmen...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Valley MA,Heard KJ,Ginde AA,Lezotte DC,Lowenstein SR

    更新日期:2012-08-01 00:00:00

  • Effect of visual cues, vital signs, and protocols on triage: a prospective randomized crossover trial.

    abstract:STUDY OBJECTIVES:We sought to compare triage designations derived from in-person and telephone interviews and systematically examine the effect of visual cues, vital signs, and complaint-based protocols on the triage process. METHODS:We conducted a 2-phase, prospective, observational study employing a randomized, cros...

    journal_title:Annals of emergency medicine

    pub_type: 临床试验,杂志文章,随机对照试验


    authors: Salk ED,Schriger DL,Hubbell KA,Schwartz BL

    更新日期:1998-12-01 00:00:00

  • The effect of axial traction during orotracheal intubation of the trauma victim with an unstable cervical spine.

    abstract::Axial (in-line) traction is recommended as a stabilizing maneuver during orotracheal intubation of a trauma victim with a potential cervical spine injury. There are no published data demonstrating the safety of this technique in trauma patients with an unstable cervical spine. In our study, 17 victims of blunt traumat...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Bivins HG,Ford S,Bezmalinovic Z,Price HM,Williams JL

    更新日期:1988-01-01 00:00:00

  • Pediatric urinary tract infection: does the evidence support aggressively pursuing the diagnosis?

    abstract::The epidemiology of pediatric fever has changed considerably during the past 2 decades with the development of vaccines against the most common bacterial pathogens causing bacteremia and meningitis. The decreasing incidence of these 2 conditions among vaccinated children has led to an emphasis on urinary tract infecti...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章,评审


    authors: Newman DH,Shreves AE,Runde DP

    更新日期:2013-05-01 00:00:00

  • Cimetidine protection against alpha-amanitin hepatotoxicity in mice: a potential model for the treatment of Amanita phalloides poisoning.

    abstract::The ingestion of the mushroom Amanita phalloides is associated with hepatic necrosis appearing clinically two to three days after ingestion. The mechanism of this toxicity is unknown, and no reliable antidote is available. Because of the similarity of Amanita poisoning to other toxins affecting cytochrome P450, we inv...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Schneider SM,Borochovitz D,Krenzelok EP

    更新日期:1987-10-01 00:00:00

  • Incidence of clinically important biphasic reactions in emergency department patients with allergic reactions or anaphylaxis.

    abstract:STUDY OBJECTIVE:Allergic reactions are common presentations to the emergency department (ED). An unknown proportion of patients will develop biphasic reactions, and patients are often monitored for prolonged periods to manage potential reactions. We seek to determine the incidence of clinically important biphasic react...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Grunau BE,Li J,Yi TW,Stenstrom R,Grafstein E,Wiens MO,Schellenberg RR,Scheuermeyer FX

    更新日期:2014-06-01 00:00:00

  • Seizures due to maprotiline overdose.

    abstract::Maprotiline, a new tetracyclic antidepressant, has a pattern of toxicity that is different from that of tricyclics. Maprotiline overdosage appears more likely to cause seizures but less likely to cause the peripheral autonomic and cardiac manifestations seen with tricyclics. Two cases of maprotiline overdose resulting...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Northup L,Reed G,McAnalley B,Anderson RJ

    更新日期:1984-06-01 00:00:00

  • Houston's medical disaster response to Hurricane Katrina: part 1: the initial medical response from Trauma Service Area Q.

    abstract::After Hurricane Katrina hit the Gulf Coast on August 29, 2005, thousands of ill and injured evacuees were transported to Houston, TX. Houston's regional disaster plan was quickly implemented, leading to the activation of the Regional Hospital Preparedness Council's Catastrophic Medical Operations Center and the rapid ...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Hamilton DR,Gavagan TF,Smart KT,Upton LA,Havron DA,Weller NF,Shah UA,Fishkind A,Persse D,Shank P,Mattox K

    更新日期:2009-04-01 00:00:00

  • A community survey of the potential use of thrombolytic agents for acute myocardial infarction.

    abstract::We surveyed all patients admitted to nine community hospital coronary care units to determine what proportion could be candidates for thrombolytic therapy. During the 12-month study period, there were 4,115 admissions for possible acute myocardial infarction, and 1,076 (26%) had a discharge diagnosis of myocardial inf...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Eisenberg MS,Ho MT,Schaeffer S,Litwin P,Larsen MP,Hallstrom AP,Weaver DW

    更新日期:1989-08-01 00:00:00

  • Impact of rapid entry and accelerated care at triage on reducing emergency department patient wait times, lengths of stay, and rate of left without being seen.

    abstract:STUDY OBJECTIVE:Patients who leave before being seen by a physician represent a significant problem for many emergency departments (EDs). We sought to determine the effect of a new ED rapid entry and accelerated care at triage (REACT) process on the frequency of patients who leave before being seen. METHODS:We conduct...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Chan TC,Killeen JP,Kelly D,Guss DA

    更新日期:2005-12-01 00:00:00

  • Effect of emergency department crowding on time to antibiotics in patients admitted with community-acquired pneumonia.

    abstract:STUDY OBJECTIVE:We hypothesize that emergency department (ED) volume and increased patient complexity are associated with lower quality of care, as measured by time to antibiotics for patients being admitted with community-acquired pneumonia. METHODS:This was a cross-sectional study at a university tertiary care hospi...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Fee C,Weber EJ,Maak CA,Bacchetti P

    更新日期:2007-11-01 00:00:00

  • Survival rates from out-of-hospital cardiac arrest: recommendations for uniform definitions and data to report.

    abstract::Survival rates for out-of-hospital cardiac arrest vary widely among locations. We surveyed the definitions used in published studies of out-of-hospital cardiac arrest. Data from 74 studies involving 36 communities showed survival rates ranging from 2% to 44%. There were five different case definitions and 11 different...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Eisenberg MS,Cummins RO,Damon S,Larsen MP,Hearne TR

    更新日期:1990-11-01 00:00:00

  • An Age-Adjusted D-dimer Threshold for Emergency Department Patients With Suspected Pulmonary Embolus: Accuracy and Clinical Implications.

    abstract:STUDY OBJECTIVE:We determine the accuracy of an age-adjusted D-dimer threshold to detect pulmonary embolism in emergency department (ED) patients older than 50 years and describe current ED practices when evaluating possible pulmonary embolism. METHODS:This was a retrospective study of ED encounters for suspected pulm...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Sharp AL,Vinson DR,Alamshaw F,Handler J,Gould MK

    更新日期:2016-02-01 00:00:00

  • Sixteen years of croup in a Western Australian teaching hospital: effects of routine steroid treatment.

    abstract:STUDY OBJECTIVE:To describe the experience of croup at Princess Margaret Hospital for Children (PMH), the only tertiary pediatric hospital in Western Australia, from 1980 through 1995 with reference to the introduction of routine steroid treatment in the ICU in 1989, in the general hospital wards from 1989 through 1993...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Geelhoed GC

    更新日期:1996-12-01 00:00:00

  • Comparison of electronic pharmacy prescription records with manually collected medication histories in an emergency department.

    abstract:STUDY OBJECTIVE:Medication history is an essential part of patient assessment in emergency care. Patient-reported medication history can be incomplete. We study whether an electronic pharmacy-sourced prescription record can supplement the patient-reported history. METHODS:In a community hospital, we compared the patie...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Fung KW,Kayaalp M,Callaghan F,McDonald CJ

    更新日期:2013-09-01 00:00:00

  • Soluble intercellular adhesion molecule-1 as a predictor of early adverse events in patients with chest pain compatible with myocardial ischemia.

    abstract:STUDY OBJECTIVE:Inflammation plays an important role in acute coronary syndromes, and some evidence indicates that patients with a more pronounced vascular inflammatory response have a poorer outcome. Soluble intercellular adhesion molecule-1 (sICAM-1) is a specific marker for vascular endothelial cell activation. The ...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Hillis GS,Terregino C,Taggart P,Killian A,Zhao N,Kaplan J,Dalsey WC,Mangione A

    更新日期:2001-09-01 00:00:00

  • Sports-related pneumothorax.

    abstract::Pneumothorax and pneumomediastinum are rare complications of athletic activity. Spontaneous pneumothorax has been reported in association with several sports, but reports of pneumothorax associated with blunt trauma sustained during sporting activity are rare. We present a case series of patients in whom pneumothorax ...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Partridge RA,Coley A,Bowie R,Woolard RH

    更新日期:1997-10-01 00:00:00

  • Bleeding complications following initiation of thrombolytic therapy for acute myocardial infarction: a comparison of helicopter-transported and nontransported patients.

    abstract:STUDY OBJECTIVE:To evaluate the effect of helicopter transport of acute myocardial infarction (AMI) patients after initiation of thrombolysis on bleeding complications through hospital discharge. DESIGN:Prospectively identified incidence (cohort) study. SETTING:Air medical service of tertiary-care teaching hospital. ...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Fromm RE Jr,Hoskins E,Cronin L,Pratt CM,Spencer WH 3rd,Roberts R

    更新日期:1991-08-01 00:00:00

  • Prehospital Index: a scoring system for field triage of trauma victims.

    abstract::The Prehospital Index (PHI) is a triage-oriented trauma severity scoring system comprising four components: systolic blood pressure, pulse, respiratory status, and level of consciousness, each scored 0 to 5. The PHI was developed after analysis of 313 cases to provide an objective prehospital scoring system for distin...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Koehler JJ,Baer LJ,Malafa SA,Meindertsma MS,Navitskas NR,Huizenga JE

    更新日期:1986-02-01 00:00:00

  • Failure of cross clamping the thoracic aorta to control intra-abdominal bleeding.

    abstract::The efficiency of cross clamping the thoracic aorta for cases of massive hemorrhage and impending cardiac arrest is questionable. We present two cases of major intra-abdominal aortic injury in which the bleeding could not be controlled by cross clamping the thoracic aorta. Multiple collateral pathways around the clamp...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Brotman S,Oster-Granite M,Cox EF

    更新日期:1982-03-01 00:00:00

  • Coacaethylene levels in patients who test positive for cocaine.

    abstract:STUDY OBJECTIVE:To determine the presence of cocaethylene, an active metabolite of the combination of cocaine and ethanol, among trauma patients who test positive for cocaine. METHODS:We assembled a case series of 416 consecutive urban trauma center patients with major trauma. Urine was tested for the presence of the ...

    journal_title:Annals of emergency medicine

    pub_type: 杂志文章


    authors: Brookoff D,Rotondo MF,Shaw LM,Campbell EA,Fields L

    更新日期:1996-03-01 00:00:00