Incomplete Data Collection Research Articles

Reliable Data Collection with Mobile Sink Using Seamless Handover in Duty Cycled Based WSNs

Providing successful data collection in transmitter-initiated wireless sensor networks with mobile Sink (WSN-MS) scenarios is a primary goal of a myriad of critical applications in real world. Unfortunately, the problem of broken links which may occur during data transmission between a source node and a mobile Sink may cause inevitably incomplete data collection. To overcome this challenging issue, we propose in this paper a seamless handover mechanism performed on asynchronous duty cycled MAC protocol on the basis of neighborhood information. By measuring continuously the signal quality of ACKnowledgment messages of transmitted Data during a 1-hop communication, this mechanism allows the source node to continue transmitting data to the mobile Sink using a suitable neighbor node as relay in the case where the Sink node leaves the radio range in direction of that neighbor node. The asynchronous protocol XMAC (without handover) has been chosen as a basic protocol on which we designed our contribution named HXMAC (XMAC with handover). The later was implemented and evaluated using a powerful simulation tool. Experimental results based on the comparison between HXMAC and XMAC clearly showed that handover mechanism is a suitable technique to promote significantly reliability in WSN-MS data collection operation.

EFFECTS OF BOVINE LIPID EXTRACT SURFACTANT (BLES) ADMINISTRATION IN PRETERM INFANTS TREATED FOR RESPIRATORY DISTRESS SYNDROME

BACKGROUND: Surfactant therapy is effective in improving the clinical outcomes of premature infants with respiratory distress syndrome (RDS). Bovine Lipid Extract Surfactant (BLES®) is commonly used to treat RDS in premature infants in Neonatal Intensive Care Units (NICU) across Canada. OBJECTIVES: To describe the length of time to wean to room air following the administration of BLES for the treatment of RDS in premature infants as per local evidence-based practice guideline. DESIGN/METHODS: Retrospective review of data collected from infants born < 37 weeks with RDS treated with surfactant replacement therapy between February 1, 2015 and March 1, 2016. Data were analysed to determine the timing of initial surfactant administration, length of time to wean to room air and number of doses required. Infants were sub grouped within gestational age stratum; 230 weeks to 276 weeks (extreme preterm - group 1), 280 weeks to 316 weeks (very preterm - group 2) and 320 weeks to 366 weeks (group 3). RESULTS: Ninety eight premature infants with RDS were treated with surfactant during the study period. Twenty one infants were excluded due to incomplete data collection (16/21) and ongoing oxygen requirement prior to second dose of surfactant (5/21).Seventy seven infants were analysed; mean gestational age and birth weight were 286 weeks (SD 3.5) and 1250 grams (SD 602). Forty infants (52%) were in group 1, 21 (27%) in group 2 and 16 (21%) in group 3.The initial dose of surfactant in group 1 was given at a median time of 29 minutes (IQR=24) after birth compared to 150 minutes (IQR=595) in group 2 and 990 minutes (IQR=1973) in group 3 (c2=21.89, p<0.001). Median length of time to wean to room air was 14 minutes (IQR=51) in group 1, 10 minutes (IQR=48) in group 2, and 10 minutes (IQR=33) in group 3 (p=0.88). Only 6% of all infants required repeated doses of BLES, 4 infants in group 1 and 1 infant in group 3. CONCLUSION: Extreme preterm infants received their initial dose of BLES® earlier in their RDS management. Given the rapid response to BLES® in the entire patient population, careful monitoring of ventilator parameters should be made, allowing for rapid weaning and eventual extubation after surfactant administration.

Determinants of physicians’ intention to collect data exhaustively in registries: an exploratory study in Bamako’s community health centres

The incomplete collection of health data is a prevalent problem in healthcare systems around the world, especially in developing countries. Missing data hinders progress in population health and perpetuates inefficiencies in healthcare systems. This study aims to identify the factors that predict the intention of physicians practicing in community health centres of Bamako, Mali, to collect data exhaustively in medical registries. A cross sectional study. In January and February 2011, we conducted a study with a random sample of thirty two physicians practicing in community health centres of Bamako, using a questionnaire. Data was analyzed by using descriptive statistics, correlations and linear regression. Trained investigators administered a questionnaire measuring physicians' sociodemographic and professional characteristics as well as constructs from the Theory of Planned Behaviour. Our results showed that physicians' intention to collect data exhaustively is influenced by subjective norms and by the physician's number of years in practice. the results of this study could be used as a guide for health workers and decision makers to improve the quality of health information collected in community health centers.

Water intake: validity of population assessment and recommendations.

Good hydration is vital for good health and well-being. Until recently, there was little interest in collecting data on water and drink and beverage intake. However, there is increasing evidence that a low water intake or mild dehydration may be linked with the risk of chronic diseases. Accurate estimates of intake in populations are essential to explore these relationships. This will enable the identification of specific populations at the risk of low water intake and allow exposure assessment of potential contaminates and specific nutrients present in drinks and beverages. In addition, data from these population studies are used as the basis of national and international recommendations on water intake and to set and evaluate national health policies. For example, EFSA based their recommendations on data from population studies from 13 European countries. The range of intakes varied from 720 to 2621 mL/day; this diversity cannot be explained by environmental differences alone. However, this variability may, at least partially, be explained by the inconsistency in methodologies used as none of surveys used a dietary assessment tool validated for total water intake or beverage and drink intake. It is reasonable to suggest that this may result in incomplete data collection and it raises questions on the validity of the recommendations. The relationship between water consumption and health warrants further investigation, and robust methodologies are essential to ensure that these data are accurate and useful for setting public health priorities and policies.

Abstract 276: Variation of Quality of Life Data Collection Across INTERMACS Sites

Purpose: To capture health-related quality of life (HRQOL) benefits and[[Unable to Display Character: &amp;#8232;]] risks of mechanical circulatory support (MCS), the INTERMACS registry expanded collection of HRQOL data to include the Kansas City[[Unable to Display Character: &amp;#8232;]] Cardiomyopathy Questionnaire (KCCQ) prior to and after MCS (beginning[[Unable to Display Character: &amp;#8232;]] 6/12). To better understand reasons for incomplete data collection, we examined patient- and site-associated factors. Methods: Descriptive analyses and hierarchical logistic regression were used to examine the frequency &amp; site variability (median odds ratios [MOR]) for each reason for not collecting the KCCQ at baseline &amp; at three months. Results: The KCCQ was not collected in 43.4% (2031 of 4682) (range across sites: 0-[[Unable to Display Character: &amp;#8232;]]100%) &amp; 34.6% (1282 of 3702), (0-100%) of pts. at baseline and 3 months. The most common reason for incomplete KCCQ data at baseline was that the patient was too sick (14.4%) &amp; consent was not obtained (12.2%); at 3 months,[[Unable to Display Character: &amp;#8232;]] the key reason was that the coordinator was too busy/forgot (12.4%). Variations across sites, on a logistic scale, reveal no significant variation[[Unable to Display Character: &amp;#8232;]] in those who were too sick at baseline, but significant variation [[Unable to Display Character: &amp;#8232;]]in all other reasons (Fig 1). Similarly, administrative reasons for incomplete data at three months were much more variable than patient-centered[[Unable to Display Character: &amp;#8232;]] reasons. If a mechanism were created for assigning KCCQ values to the “too sick” patients then the completion rates would be 71.0% at baseline and 69.1% at three months.[[Unable to Display Character: &amp;#8232;]] Conclusion: Sites vary substantially in the completeness of KCCQ data due to both patients and administrative reasons. However, the sources of missing data need to be considered in analyses; most importantly, sites need to increase commitment to complete data collection.

The great Indian calorie debate: Explaining rising undernourishment during India’s rapid economic growth

The prevalence of undernourishment in India – the percent of people consuming insufficient calories to meet their energy requirements – has been rising steadily since the mid 1980s. Paradoxically, this period has been one of robust poverty reduction and rapid economic growth. The reasons for the apparent reductions in calorie consumption underlying increased undernourishment have been the subject of intense debate both within India and internationally. This paper critically reviews this debate, finding that is has taken place outside of the context of India’s recent nutrition and epidemiological transitions, which appear to have brought with them increased, not decreased, food consumption. The debate has also taken place under the unchallenged assumption that the data on which the conflicting trends are based, collected as part of the country’s Household Consumption and Expenditure Surveys (HCESs), are reliable. The paper provides supporting literature and empirical evidence that a probable key source of the calorie decline is incomplete collection of data on food consumed away from peoples’ homes, which is widespread and rapidly increasing. Complete measurement of this food source in the HCESs of all developing countries is vital for accurate measurement of both undernourishment and poverty – and for resolving the Indian calorie debate.

Revisional bariatric surgery following failed primary laparoscopic sleeve gastrectomy: a systematic review.

Revisional bariatric surgery following laparoscopic sleeve gastrectomy (LSG) failure presents a clinical challenge for the bariatric surgeon. Limited evidence exists in selecting the appropriate revisional operation: laparoscopic gastric bypass (LGB), laparoscopic re-sleeve gastrectomy (LRSG), or other surgical intervention (OSI), to address weight regain. We systematically reviewed the literature to assess the efficacy of existing revisional surgery. A comprehensive search of electronic databases (e.g., Medline, Embase, Scopus, Web of Science, and the Cochrane Library) was completed. All randomized controlled trials, non-randomized comparison study, and case series were included. Eleven primary studies (218 patients) were identified and included in the systematic review. Studies were grouped into three main categories: LGB, LRSG, and OSI. Preoperative body mass index (BMI) was 41.9 kg/m(2) (LGB), 38.5 kg/m(2) (LRSG), and 44.4 kg/m(2) (OSI). After conversion to LGB, BMI decreased to 33.7 and 35.7 kg/m(2) at 12 and 24 months of follow-up, respectively. Excess weight loss (EWL) was 60 and 48 % over the same periods. After LRSG, BMI decreased to 30.4 and 35.3 kg/m(2) with corresponding EWL of 68 and 44 %, at 12 and 24 months, respectively. After OSI, BMI decreased to 27.3 kg/m(2) with an EWL of 75 % at 24-month follow-up but could not be analyzed due to incomplete data collection in primary studies. Both LGB and LRSG achieve effective weight loss following failed LSG. The less technically challenging nature of LRSG may be more widely applicable. Further research is required to elicit sustainability in long-term weight loss benefits.

Support Vector Regression for Large Domain Adaptation

Incomplete data collection in regression analysis would lead to low prediction performance,which aises the issue of domain adaptation.It is well known that support vector regression(SVR) is equivalent to center-constrained minimum enclosing ball(CC-MEB).Also in solving the problem of how to effectively transfer the knowledge between the two fields,new theorems reveal that the difference between two probability distributions from two similar domains only depends on the centers of the two domains' minimum enclosing balls.Based on these developments,a fast adaptive-core vector regression(A-CVR) algorithm is proposed for large domain adaptation.The proposed algorithm uses the center of the source domain's CC-MEB to calibrate the center of the target domain's in order to improve the regression performance of the target domain.Experimental results show that the proposed domain adaptive algorithm can make up for the lack of data and greatly improve the performance of the target domain regression.

The stages of extrication: a prospective study

BackgroundMany patients will require extrication following a motor vehicle collision (MVC). Little information exists on the time taken for the various stages of extrication.ObjectiveTo report the time taken for the...

The Great Indian Calorie Debate: Explaining Rising Undernourishment during India's Rapid Economic Growth

SummaryThe prevalence of undernourishment in India – the percent of people consuming insufficient calories to meet their energy requirements – has been rising steadily since the mid‐1980s. Paradoxically, this period has been one of robust poverty reduction and rapid economic growth. The reasons for the apparent reductions in calorie consumption underlying increased undernourishment have been the subject of intense debate both within India and internationally. This paper critically reviews this debate, finding that is has taken place outside of the context of India's recent nutrition and epidemiological transitions, which appear to have brought with them increased, not decreased, food consumption. The debate has also taken place under the unchallenged assumption that the data on which the conflicting trends are based, collected as part of the country's Household Consumption and Expenditure Surveys (HCESs), are reliable. The paper provides supporting literature and empirical evidence that one key factor driving the measured calorie decline is incomplete collection of data on food consumed away from peoples’ homes, which is widespread and rapidly increasing. The India example shows that complete measurement of this food source in the HCESs of all countries is vital for accurate measurement of undernourishment and, indeed, poverty at national, regional and global levels.

The Impact of Increased Skin‐to‐Skin Contact on Breastfeeding Neonates on Exclusive Breastfeeding at 4 and 8 Weeks Postpartum

<h2>Paper Presentation</h2><h3>Objective</h3> To investigate the research question: Is there a relationship between the number of minutes of skin‐to‐skin (STS) contact between mother and infant during hospitalization and the rate of breastfeeding exclusivity at 4 and 8 weeks postpartum? <h3>Design</h3> Descriptive correlational study. <h3>Setting</h3> Urban nonprofit hospital with an average of 1,100 births per year. <h3>Sample</h3> Term pregnant women who had a vaginal delivery of a well newborn with intent to exclusively breastfeed. Sixty‐five women were enrolled into the study. Thirty women were excluded (cesarean delivery, infant admission to level II nursery, incomplete data collection). Thirty‐five women completed the inpatient data collection and follow‐up telephone calls at four and 8 weeks postpartum to assess breastfeeding exclusivity. <h3>Methods</h3> Subjects were recruited from a midwifery practice during prenatal care. At birth, newborns were placed STS with their mothers. Mothers were educated on how to provide STS for their newborns while in the hospital and maintained a log of the number of minutes of STS while in the hospital. Follow‐up phone calls were made at 4 and 8 weeks postpartum for assessment of exclusive breastfeeding, using the Index of Breastfeeding Status. <h3>Results</h3> Data were analyzed using correlation and chi‐square. The total length of time of STS in the hospital was not correlated with breastfeeding exclusivity at 4 and 8 weeks. However, STS occurring immediately at birth was positively associated with exclusive breastfeeding at 4 weeks postpartum. Increased times to STS and increased time to first breastfeeding were negatively associated with breastfeeding exclusivity. Additionally, infants with increased length of stay and those who were supplemented with formula were less likely to be exclusively breastfed at 4 and 8 weeks postpartum. <h3>Conclusion/Implications for Nursing Practice</h3> STS starting at birth was found to be significant for increasing breastfeeding exclusivity. Implications for practice include changing nursing and medical practice at delivery and placing healthy infants STS with their mothers at birth instead of routinely handing infants to the resuscitation team. Weaknesses of this study include recall bias and possible self‐selection bias in recruiting women with intent to exclusively breastfeed.

AB0019 A PLS multivariate model to predict RA radiological severity by selecting key predictors from a large panel of SNPS and environmental factors

BackgroundThe mechanisms contributing to the development of rheumatoid arthritis and to the development of tissue damage are complex [1]. Candidate gene association and linkage studies have recently identified a role...

Thermoacoustic tomography with an arbitrary elliptic operator

Thermoacoustic tomography is a term for the inverse problem of determining of one of the initial conditions of a hyperbolic equation from boundary measurements. In past publications, both stability estimates and convergent numerical methods for this problem were obtained only under some restrictive conditions imposed on the principal part of the elliptic operator. In this paper, logarithmic stability estimates are obtained for an arbitrary variable principal part of that operator. Convergence of the quasi-reversibility method to the exact solution is also established for this case. Both complete and incomplete data collection cases are considered.

Effect of Inspiratory Muscle Training Before Cardiac Surgery in Routine Care

Inspiratory muscle training (IMT) before cardiac surgery has proved to be a promising intervention to reduce postoperative pneumonia in a randomized controlled trial setting. Effects of IMT in routine care have not been reported. The purpose of this study was to investigate the effect of IMT before cardiac surgery on postoperative pneumonia in routine care at a Dutch university medical center using propensity scoring. This was an observational cohort study. All candidates for cardiac surgery were preoperatively stratified by a physical therapist for low risk or high risk for postoperative pulmonary complications. Patients at high risk either engaged in an unsupervised IMT program (20 minutes a day) at home for at least 2 weeks before surgery (group 1) or received usual care (no IMT) (group 2). Results in terms of outcome measures were adjusted with propensity scores to reduce bias caused by nonrandom treatment assignment. The results showed that of the 94 patients at high risk in group 1, 1 patient (1.1%) developed a postoperative pneumonia. In group 2, 8 out of the 252 patients at high risk (3.2%) developed this pulmonary complication (adjusted odds ratio=0.34, 95% confidence interval=0.04-3.38). No significant differences were found regarding median (25th-75th percentile) ventilation time (7 [5-9] hours versus 7 [5-10] hours), length of stay in the intensive care unit (23 [21-24] hours versus 23 [21-25] hours), or total postoperative length of stay (7 [6-11] days versus 7 [5-9] days). The most important limitations of this study were confounding, incomplete data collection, and a low incidence of the primary outcome. Propensity scoring is believed to be a valuable tool of great potential interest to researchers in the field of observational studies. Whether IMT in routine care resulted in less postoperative pneumonia cannot be concluded.

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Introduction: In critical illness, increasing oxygen delivery (DO2) in an attempt to raise oxygen consumption (VO2) was previously thought to be beneficial. Further studies however showed that while patients whose VO2 increased with increased DO2 did well, those whose VO2 did not increase in spite of high DO2 had extremely poor outcomes. This suggests that oxygen extraction is critical in these patients. Hypothesis: Thiamine, a co-factor of pyruvate dehydrogenase and necessary for aerobic metabolism, may increase oxygen extraction in critically ill patients. Methods: This was an open-label, pilot study. 20 critically ill, mechanically ventilated adult patients were enrolled in the medical and surgical ICU’s at our tertiary care medical center. 4 were excluded from analysis due to incomplete data collection. All patients were connected to the Cheetah non-invasive cardiac output monitor for continuous cardiac index(CI) monitoring, and to the GE Compact Anesthesia monitor for continuous measurement of VO2. After baseline CI and VO2 data were collected for 3 hours, a single dose of 200mg IV thiamine was administered. VO2 and CI were monitored for an additonal 6 hours after thiamine was given. Thiamine levels and lactate were collected at the beginning and end of the study. Results: The primary outcome was change in VO2. 16 patients were included in the analysis. There was a statistically significant increase in VO2 after thiamine (average increase of 16ml/min +/- SE 8, p= 0.049). These results remained the same after adjusting for changes in cardiac index (CI). In patients with an average CI greater than our cohort’s median value of 2.9L/m2, there was an increase in VO2 of 71ml/min (+/- 16, p<0.0001) after thiamine administration. Thiamine had no effect on VO2 in patients with reduced CI(<2.5L/m2). Thiamine levels ranged from undetectable in one patient to 73nmol/L (reference range 9-44nmol.L). There was no association between initial thiamine level and change in VO2 after thiamine administration. Conclusions: We found that thiamine administration increases VO2 in critically ill patients. There was a larger effect in patients with higher than average CI. These effects were not associated with baseline thiamine level.

Increased cancer risk with drug use among patients with diabetes: Are the biased methods the culprit?

Increased cancer risk with drug use among patients with diabetes: Are the biased methods the culprit?

PRM20 Empirical Analysis Shows Reduced Cost Data Collection May Be an Efficient Method in Economic Clinicl Trials

To assess the validity of cost calculation from incomplete data collection and point out its consequence on bias and on precision of study results. Over a one-year period resource use data from 234 elderly patients with myocardial infarction were collected quarterly. Applying unit costs, costs for each quarter were estimated. To examine different strategies of incomplete data collection, two different methods (inter-/extrapolation) with three different time frames (omitting quarter two and/or three) were applied and compared with complete data collection. Sample size was recalculated in response to the variation of cost estimates due to incomplete data collection. Sum of cost estimation from complete and incomplete data collection in the case of omitting information of quarter two or three showed no significant difference. When the time sampling included only 50% of the full information (omitting quarter two and three) costs were significantly lower by 3.9% (extrapolation) and 4.6% (interpolation). Generally, an increase in the standard deviation by 1% leads to an increase in sample size by 2% in the case of a single outcome. Thus, based on observed increased standard deviation due to incomplete cost collection a larger sample size by about 3% would be required. This would be efficient, since more time is saved due to incomplete data collection than extra time is required for additional patients. In economic evaluation, cost data can be collected efficiently by reducing frequency of data collection. This can be achieved by data collection for shorter periods (incomplete data collection) or extending recall windows (complete data collection). When applying the method of incomplete data collection, sample size calculation has to be modified due to increased standard deviation. This approach is suitable to enable economic evaluation with lower costs to both study participants and investigators.

Empirical analysis shows reduced cost data collection may be an efficient method in economic clinical trials

BackgroundData collection for economic evaluation alongside clinical trials is burdensome and cost-intensive. Limiting both the frequency of data collection and recall periods can solve the problem. As a consequence, gaps in survey periods arise and must be filled appropriately. The aims of our study are to assess the validity of incomplete cost data collection and define suitable resource categories.MethodsIn the randomised KORINNA study, cost data from 234 elderly patients were collected quarterly over a 1-year period. Different strategies for incomplete data collection were compared with complete data collection. The sample size calculation was modified in response to elasticity of variance.ResultsResource categories suitable for incomplete data collection were physiotherapy, ambulatory clinic in hospital, medication, consultations, outpatient nursing service and paid household help.Cost estimation from complete and incomplete data collection showed no difference when omitting information from one quarter. When omitting information from two quarters, costs were underestimated by 3.9% to 4.6%.With respect to the observed increased standard deviation, a larger sample size would be required, increased by 3%. Nevertheless, more time was saved than extra time would be required for additional patients.ConclusionCost data can be collected efficiently by reducing the frequency of data collection. This can be achieved by incomplete data collection for shortened periods or complete data collection by extending recall windows. In our analysis, cost estimates per year for ambulatory healthcare and non-healthcare services in terms of three data collections was as valid and accurate as a four complete data collections. In contrast, data on hospitalisation, rehabilitation stays and care insurance benefits should be collected for the entire target period, using extended recall windows. When applying the method of incomplete data collection, sample size calculation has to be modified because of the increased standard deviation. This approach is suitable to enable economic evaluation with lower costs to both study participants and investigators.Trial registrationThe trial registration number is ISRCTN02893746

Corneal thickness after overnight wear of an intraocular pressure fluctuation contact lens sensor

To assess the effect of overnight wear of a contact lens-based sensor (CLS) for monitoring of 24-hr intraocular pressure (IOP) fluctuations on central corneal thickness (CCT). Changes in the CCT, mid-peripheral corneal thickness and central corneal radius (CCR) during overnight CLS wear in 20 eligible patients with ocular hypertension or established glaucoma were prospectively studied using ultrasound pachymetry and topography. Corneal thickness and CCR changes were evaluated from pre-to-postsleep, with the fellow eye as control. Paired t-test or Wilcoxon signed-rank test was used as appropriate and with α = 0.05. Relationship between the IOP profile recorded by the CLS and the pre-to-postsleep corneal thickness differences was assessed using the Spearman correlation coefficient. After CLS wear, mean CCT had changed from 523 to 537 μm (p = 0.015) in the study eye and from 518 to 522 (p = 0.206) in the fellow eye (n = 15). There was no difference in CCT change between eyes (p = 0.075). There were no statistically significant changes in horizontal or vertical CCR in either eye (p > 0.05 for all). No correlation was found between the pre-to-postsleep differences in the CLS signal and the pre-to-postsleep differences in ultrasound CCT measurements (p = 0.974). The continuous IOP monitoring does not appear to be affected by differences in corneal thickness that occur during overnight CLS wear, although the CLS did induce some corneal swelling. This effect was not statistically significantly different from the control eye and does not seem to influence the CLS IOP profile.

Bedside sonographic measurement of the inferior vena cava caval index is a poor predictor of fluid responsiveness in emergency department patients

Sonographic measurement of the inferior vena cava (IVC) caval index predicts central venous pressure in ED patients. Fluid responsiveness (FR) is a measure of preload dependence defined as an increase in cardiac output secondary to volume expansion. We sought to determine if the caval index is an accurate measurement of FR in ED patients. We conducted a prospective, observational trial at an urban, academic, adult ED with an annual census >105 000. Included patients were clinically suspected of eu- and hypovolemia. Excluded patients were <18 years old, pregnant, incarcerated, sustained significant trauma or unable to consent. Supine IVC diameter was measured by bedside ultrasonography (M-Turbo; Sonosite, Bothwell, WA, USA). Caval index = [(expiratory IVC diameter - inspiratory IVC diameter)/expiratory IVC diameter] × 100. FR was defined as an increase in the cardiac index by >10% by impedance cardiography (BioZ; Sonosite) following passive leg raise. The primary outcome was analysed using Spearman correlations for non-parametric data and the area under the receiver operating characteristics curve by Wilcoxon method. Thirty patients were enrolled; four were excluded because of incomplete data collection. Thirty-one per cent (95% CI 13-48) of the patients were FR. The mean initial caval and cardiac index were 15.8% (95% CI 9.5-22) and 2.9 L/min/m(2) (95% CI 2.6-3.2), respectively. Caval index did not predict FR (receiver operating curve = 0.46, 95% CI 0.21-0.71, P = 0.63). Bedside sonographic measurement of IVC caval index does not predict FR in a heterogeneous ED patient population. Further research using this technique in targeted patient subsets and a variety of shock etiologies is needed.